Jahresbericht 2010

Jahresbericht / Annual Report

2010

INM – Leibniz-Insti tut für Neue Materialien

Ein Insti tut der Leibniz-Gemeinschaft

INM – Leibniz Insti tute for New Materials

An Insti tute of the Leibniz Associati on

Saarbrücken

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Inhalt / Contents

Vorwort / Preface 6

Wissenschaft liche Arti kel / Scienti fi c Arti clesMorphology controlled preparati on of monodisperse TiO2 nanorods and nanoparti cles for opti cal nanocomposites 11

Bioinspired pressure actuated adhesive system 17

Biological Materials – Bioinspirati on on Diff erent Length Scales 22

Micro-/nanostructured alumina as model surface to study topography eff ects on cell-surface interacti ons 27

The intracellular localizati on of inorganic engineered versus biogenic materials: a comparison 32

“Gecko-Workshop 2010” – INM initi ates new worldwide conference series 41

Gruppenberichte / Group Reports

Nanomere / Nanomers 47

Nanoprotect / Nanoprotect 51

Opti sche Materialien / Opti cal Materials 55

Funkti onelle Oberfl ächen / Functi onal Surfaces 59

Nanotribologie / Nanotribology 63

Strukturbildung auf kleinen Skalen / Structure Formati on at Small Scales 67

Biomineralisati on / Biomineralizati on 71

CVD/Biooberfl ächen / CVD/Biosurfaces 75

Nano Zell Interakti onen / Nano Cell Interacti ons 79

Modelling/Simulati on / Modellierung/Simulati on 82

Anwendungszentrum NMO/Verfahrenstechnik / Applicati on Center NMO/Chemical Engineering 86

Servicegruppe Bibliothek / Service Group Library 88

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Servicegruppe Chemische Analytik / Service group Chemical Analysis 89

Servicegruppe Physikalische Analytik / Service Group Physical Analysis 91

Servicegruppe Engineering / Service Group Engineering 93

Servicegruppe Werkstoffprüfung/Pulversynthese / Service Group Materials Testing/Powder Synthesis 94

Fakten und Zahlen / Facts and Figures

Statusbericht / Status report 97

Mitglieder des Kuratoriums / Members of the Board of Directors 101

Mitglieder des wissenschaftlichen Beirats / Members of the Scientific Board 101

Aktivitäten in Gremien / Activities in committees 101

Auszeichnungen / Awards 103

Habilitation / Habilitation 103

Abgeschlossene Dissertationen / Completed doctoral theses 103

Abgeschlossene Bachelor- und Masterarbeiten / Completed bachelor and master theses 104

Doktoranden / Doctoral Students 104

Gastwissenschaftler / Guest Scientists 104

Publikationen / Publications 105

Vorträge / Talks 112

Lehrveranstaltungen / Lectures 117

Patents / Patente 119

Kooperationen / Cooperations 120

Veranstaltungen / Events 122

Organigramm / Organigram 124

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beitete Projekt NanoKon untersucht Gesundheitsauswirkungen nanoskali-ger Kontrastmittel für die medizinische Diagnostik. Bei beiden arbeiten wir ne-ben anderen nationalen Forschungs-einrichtungen insbesondere mit der Universität des Saarlandes sowie unse-ren Ausgründungen zusammen. Auch international ist das INM ein wichtiger Partner, wie das EU-Projekt CuVito zeigt. Hier wirkt der Programmbereich Nanomere an der Entwicklung einer kupferbasierten nanostrukturierten Beschichtung mit antibakterieller Wir-kung mit.

An internationaler Sichtbarkeit hat das INM im Jahr 2010 ebenfalls wesentlich dazugewonnen. Sei es das Jahrestref-fen des FANAS-Programms der Euro-pean Science Foundation, der Work-shop „Nanobrücken 2010“ mit der Fir-ma Hysitron zur Nanoindentation oder das Symposium „Bioinspired adhesion: from geckos to new products“, ein internationaler Workshop zur Gecko-Haftung (wir berichten im Textteil) – viele ausländische Teilnehmer konnten sich erstmals von der Leistungsfähig-keit des Standorts Saarbrücken über-zeugen. INM-Innovationen wurden beim ersten „Industrietag“ des INM oder bei verschiedenen Konferenzen und Messen vorgestellt.

Allen Freunden des INM – aus Wissen-schaft, Industrie, Politik und Öffentlich-keit –, die im vergangenen Jahr zu der erfolgreichen Arbeit des INM beigetra-gen haben, danke ich für ihre Unterstüt-zung. Mein besonderer Dank gilt unse-ren Mitarbeiterinnen und Mitarbeitern. Nur mit ihrem Engagement waren und sind unsere Erfolge möglich.

Prof. Dr. Eduard Arzt(Wissenschaftlicher Geschäftsführer und Vorsitzender der Geschäftsführung)

Liebe Freunde des INM,

vor allem ein Thema hat das Jahr 2010 am INM geprägt: Die Evaluierung des Instituts durch die Leibniz-Gemein-schaft war für das „neue“ INM ein gro-ßer Erfolg! Nicht nur wurde die strategi-sche Neuausrichtung „in einem über die Erwartungen hinausgehenden Maß“ er-reicht, sondern das neue wissenschaft-liche Gesamtkonzept sei schlüssig und werde „nachdrücklich unterstützt“. Die Arbeitsergebnisse unserer Programm-bereiche und Juniorforschungsgruppen wurden überwiegend als sehr gut, bei zweien sogar als exzellent bewertet. Der Leibniz-Senat hat sich im März 2011 diesem Gutachten angeschlossen und für die nächste Sieben-Jahres-Periode die Weiterförderung des INM durch Bund und Länder ohne Einschränkun-gen empfohlen. Ein wichtiger Meilen-stein für die Weiterentwicklung des Instituts!

2010 war auch ein Jahr wichtiger per-soneller Veränderungen: Im Sommer trat der Wissenschaftliche Geschäfts-führer Prof. Dr. Dr. h. c. Michael Veith in den Ruhestand ein. Wir freuen uns, dass er dem Institut als Berater weiter verbunden bleibt. Die Suche nach ei-nem geeigneten Nachfolger ist seit ge-raumer Zeit in vollem Gange. Ebenfalls im Sommer 2010 löste Dr. Roland Rol-les Jochen Flackus als kaufmännischen Geschäftsführer ab. Beiden ehemali-gen Kollegen gebührt großer Dank für ihre Arbeit seit 2005, die wesentlich für die erfolgreiche Neuausrichtung des Instituts war.

Unsere wissenschaftlichen Ergebnisse können sich weiterhin sehen lassen, Beispiele hierzu finden Sie in den wis-senschaftlichen Artikeln und Grup-penberichten. Exemplarisch erwäh-nen möchte ich drei 2010 begonnene Projekte: TIGeR, das im Programmbe-reich Nanotribologie angesiedelt ist, erforscht die Reibung des neuartigen Materials Graphen. Das im Programm-bereich Nano Zell Interaktionen bear-

Vorwort / Preface

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Interacti ons) studies potenti al health eff ects of nanoscale contrast agents for medical diagnosti cs. In both pro-jects we collaborate with other nati on-al research insti tuti ons and especially with Saarland University and with our spin-off companies. Also on the in-ternati onal level INM is an important partner, as in the EU project CuVito; herein, the Program Division Nano-mers parti cipates in the development of a copper-based nano-structured coati ng with anti bacterial eff ect.

The internati onal visibility of INM also increased signifi cantly in 2010. The an-nual meeti ng of the FANAS Program of the European Science Foundati on, the workshop “Nanobrücken 2010” on nanoindentati on together with the company Hysitron or the symposium “Bioinspired adhesion: from geckos to new products”, an internati onal work-shop about gecko-adhesion (we report on it in the text) – for the fi rst ti me, many foreign parti cipants discovered Saarbruecken is a prime research loca-ti on. INM innovati ons were presented at our fi rst industrial liaison event (“In-dustrietag”) or at several conferences and trade fairs.

I would like to thank all friends of INM –from science, industry, politi cs and public – who contributed to the suc-cessful work of INM over the last year. My parti cular thanks go to our employ-ees. It is only with their commitment and dedicati on that our success is pos-sible.

Prof. Dr. Eduard Arzt(Scienti fi c Director and Chairman)

Dear friends of INM,

Parti cularly one subject shaped the year 2010 at INM: the evaluati on of the insti tute by the Leibniz Associati on was a great success for the “new” INM! The strategic reorientati on of INM was achieved „to an extent exceeding the expectati ons” and the new scienti fi c concept was found to be conclusive and was “emphati cally supported”. The performance of our Program Divi-sions and Junior Research Groups was predominantly evaluated as very good, two of them even as excellent. The Leibniz Senate endorsed this report in March 2011 and recommended the conti nuous funding of INM by the fed-eral government and the states for the following seven-year period. A decisive milestone for the future development of the insti tute!

2010 was also a year of important per-sonnel changes: In summer, the scien-ti fi c director Prof. Dr. Dr. h. c. Michael Veith reti red; we are pleased that he conti nue to serve as an advisor. The search for a suitable successor has been in full progress for someti me. Also in summer 2010, Dr. Roland Rolles was appointed new business director, replacing Jochen Flackus. The two for-mer colleagues deserve grati tude for their eff orts since 2005, which was essenti al for the substanti al reorienta-ti on of the insti tute.

Our scienti fi c results conti nue to arouse wide spread interest. Examples can be found in the scienti fi c publica-ti ons and the group reports. Consider three projects started in 2010: The project TIGeR, which is affi liated to the Program Division Nanotribology, inves-ti gates the fricti on of the new material graphene. The project NanoKon (affi li-ated to the Program Division Nano Cell

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Wissenschaft liche Arti kel /Scienti fi c Arti cles

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thermal conditi ons. A mixture of OA and oleyl amine (OAM) has already been used to synthesize a variety of high-quality metal or metal-oxide na-nocrystals [9,10,11]. Weller et al. re-ported the controlled growth of high aspect rati o anatase TiO2 by the mod-ulati on of the hydrolysis rate in the presence of oleic acid as a surfactant at 80°C using ti tanium tetraisopropox-ide as precursor and terti ary amines as well as quaternary ammonium hydrox-ides as catalyst to promote crystalliza-ti on under mild conditi ons [ 12]. Seo et al. synthesized nanorods of transiti on metal oxides including TiO2 from the thermal reacti on of metal halides and oleic acid via acyl halide eliminati on process [ 13].

Not only is the morphology controlled synthesis of inorganic nanocrystals an important goal of advanced materials chemistry but also the preparati on of polymer nanocomposites with these parti cles. One challenge for preparing nanocomposite materials is to avoid agglomerati on of the nanofi llers in the polymer matrix that leads to poor performance of the composite [14]. Khaled et al. synthesized a TiO2-PMMA nanocomposite with a chemical bond-ing between the fi ller and the polymer matrix using meth acrylic acid as a cou-pling agent onto the parti cle surface [15]. Another method, in which parti -cles are fi rst dispersed in the monomer aft er which the mixture is polymerized has been used by Yang et al. [16]. Oleic acid capped TiO2 nanorods were di-rectly transferred into an acrylic poly-mer matrix by Sciancalepore et al. [17]. In PMMA homopolymer-based thin fi lms large and irregular clusters of nanorods were found because the PMMA methyl-carboxylate groups do not interact with oleic acid alky-lic chains present on the TiO2 surface. However uniform parti cle dispersion was achieved in PMMA-co-MA copoly-mers caused by interacti ons between

Abstract

Anatase nanoparti cles and nanorods were obtained through a modi-fi ed sol-gel route from ti tanium(IV) bis(acetylacetonate) diisopropoxide. For parti cle synthesis a mixture of oleic acid and oleyl amine has been used which off ers not only control on par-ti cle morphology but also provides or-ganically capped surface modifi ed par-ti cles, which can be readily mixed with acrylic monomers yielding completely transparent dispersions. UV- and ther-mal curing of the monomer / parti cle mixture lead to clear coati ngs without any nanoparti cle agglomerati on.

Introducti on

Titanium dioxide (TiO2) has been wide-ly used as a white pigment in many applicati on areas since its commercial producti on in the early twenti eth cen-tury. In nanoscience and nanotechnol-ogy an enormous growth of research acti viti es on TiO2 has been performed in the past decades. The wide range of its possible applicati ons in catalysis [1,2,3], opti cs, electronics [4,5], energy storage [6] and sensing [7] moved ti -tania nanoparti cles into a main focus of materials science. One-dimensional nanostructured materials including na-norods and nanowires as fi llers in na-nocomposite materials have received a vast amount of att enti on because of their unique potenti al properti es in many applicati ons where special me-chanical or opti cal properti es are re-quired.

Especially in the fast growing fi eld of nanocomposite materials metal oxide nanoparti cles with tailor-made size and shape play an important role [8]. Fatt y acids such as oleic acid (OA) and linoleic acid have been proven to be good solvents and surfactants for the growth of nanocrystals under solvo-

Morphology controlled preparati on of monodisperse TiO2 nanorods and nanoparti cles for opti cal nanocomposites

Dirk Bentz, Carsten Becker-Willinger, Sabine Schmitz-Stöwe, Michael Veith, Nanomers Group

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TEM samples were prepared by plac-ing a drop of nanoparticle dispersion in toluene onto carbon-coated copper grids. The particle size and size distri-bution in a toluene dispersion was de-termined by dynamic light scattering with a Microtrac Ultrafine Particle Size Analyzer (UPA 150).

Solvothermal synthesis in an autoclave

Into an equimolar mixture of oleic acid and oleyl amine the TADI solution was slowly added. This mixture was then transferred into a stainless steel teflon-lined autoclave and heated up to 250°C and kept at this temperature for 30 minutes in order to obtain crys-talline titania particles. Then the solu-tion was allowed to cool down to room temperature and diluted with toluene. The nanocrystals were then precipitat-ed by adding an excess of ethyl alcohol and separated by centrifugation.

Synthesis in an open reaction vessel

The completely analogues reaction mixture of OA, OAM and TADI was heated up to 250°C in an open reaction vessel under a gentle permanent argon flow to remove volatile matters. The resultant solution was then allowed to cool down to room temperature, toluene and shortly after ethyl alcohol was added to the reaction flask to precipitate the nanoparticles. The particles were separated by centrifugation.

Particle purification

Both the nanoparticles and the na-norods obtained from the above two synthesis methods can easily be redis-persed in nonpolar solvents including hexane and toluene. Slightly yellowish precipitates were obtained from the two above synthesis methods. In or-der to remove an excess of surfactant the precipitates were redispersed in toluene, again precipitated with ethyl

the methacrylic functionalities on the polymer chains and the particle sur-face whereby the oleic acid ligands can be replaced.

The goal of this work is the develop-ment of a synthesis method for opti-cal nanoparticles that provides in a one-pot reaction monodisperse sur-face modified particles without fur-ther modifying procedures. These na-noparticles should be dispersible in an acrylic monomer. After polymerization this method would result in organic/inorganic composite materials without any particle agglomeration.

Experimental

Materials

Oleic acid (OA, 90%, Aldrich), oleyl amine (OAM, 70%, Aldrich), titanium (IV) bis (acetylacetonate) diisopropox-ide (TADI, 75% solution in 2-propanol, Aldrich), hexyl methacrylate (HMA, 98%, Aldrich), 1,6-Hexanediol dimeth-acrylate (HDDMA, containing 100 ppm hydroquinone as inhibitor, Aldrich), 2,2′-Azobis(2-methylpropionitrile) (AIBN, ≥98.0%, Fluka) and Irgacure® 184 (I184, BASF Schweiz AG) were used as received.

The crystalline phase of the air-dried powder was analyzed by a Bruker D8 Advance diffractometer, equipped with a lynxeye detector and a Cu Ka ra-diation source (λ=0.15418 nm) operat-ing at a voltage of 40 kV and a current of 40 mA. The average crystallite size of the powder was calculated accord-ing to full width at half maximum of the diffraction peaks using Debye-Scherrer formula. Transmission electron micros-copy (TEM) and high resolution trans-mission electron microscopy (HRTEM) images were recorded using a JEOL JEM 2011 and a Philips CM 200 FEG microscope, respectively, both operat-ing at acceleration voltages of 200 kV.

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The morphology control of the parti -cles was realized by treati ng the reac-ti on mixture in two diff erent methods:

a) The OA/OAM/TADI mixture was transferred into a stainless steel tef-lon-lined autoclave and heated up to 250°C and kept at this temperature for 30 minutes. This synthesis produced spherical shaped nanocrystals.

b) The analogue OA/OAM/TADI mix-ture was heated up to 250°C with the same heati ng rate as before in an open reacti on vessel under a gentle perma-nent argon fl ow yielding in rod shaped nanoparti cles.

In both cases the reacti on mixtures were diluted with toluene and the par-ti cles were precipitated by adding a suffi cient amount of ethyl alcohol and separated by centrifugati on. In order to remove the excess of the surfactant, the light yellowish precipitates were redispersed again in toluene, precipi-tated with ethyl alcohol and separated by centrifugati on. Without further thermal annealing the obtained na-noparti cles show high crystallinity and are dispersible in nonpolar organic sol-vents such as toluene yielding a com-pletely clear dispersion.

It can be seen that the factors with the highest impact on the shape control are volati le components, arising from the reacti on mixture. In the synthesis using an open reacti on vessel, the re-acti on mixture is heated up to 250°C under a gentle stream of argon. Be-cause of this conti nuous fl ow of inert gas, volati le components, arising from the reacti on mixture, are removed. For this reason, this synthesis pathway can be regarded as a nonhydrolyti c sol-gel method, which promotes linear growth of TiO2 parti cles [12,13].

The situati on is diff erent when us-ing the autoclave, a closed reacti on container. In this sealed solvothermal system, volati lizati on of reacti on prod-

alcohol and separated by centrifuga-ti on. This purifi cati on procedure was repeated up to 6 ti mes without any observable loss of parti cle solubility in the nonpolar solvent toluene.

Preparati on of fi lms containing TiO2 na-noparti cles

A mixture containing HMA and HDDMA was used as an acrylic monomer. To enable UV-curing photo initi ator I 184 and for the thermal post-curing AIBN were added. Both the precipitates of the nanoparti cles and the nanorods can be mixed with the acrylic monomers. A slightly yellowish clear dispersion was obtained simply by sti rring for a few minutes. With this monomer mixture, fi lled with 5 weight% ti tania nanocrystals fi lms were prepared by coati ng microscope glass slides followed by UV curing (400W UV Panacol lamp) and a thermal post curing.

Results and Discussion

Parti cle synthesis

The combinati on of a solvent functi on and the surfactant properti es make the OA/OAM mixture an eff ecti ve tool for producing quasi monodisperse and fully redispersable opti cal nanocrystals. With the herein presented synthesis method the TiO2 nanoparti cles were prepared by thermal decompositi on of ti tanium(IV) bis(acetylacetonate) diisopropoxide (TADI) in an equimolar mixture of OA and OAM. In preliminary tests for this synthesis method, the use of TADI has shown to be advantageous. The reliability and reproducibility of the synthesis has increased signifi cantly by the use of this ti tania precursor compared to ti tanium tetraisopropoxide. One reason could be the diff erent hydrolysis and condensati on behavior of TADI because of a higher coordinati ve saturati on of the ti tanium atom in this compound [18].

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clave a simple and highly reproducible synthesis of nanoparticles was devel-oped, which makes this method inter-esting for later up-scaling to industrial scale.

To examine the crystallinity and mor-phology of the TiO2 particles X-ray diffraction (XRD) analyses were per-formed. The XRD patterns demon-strate clearly the different particle shape obtained with the analogue reaction mixture only by variation of reaction conditions. For sample prepa-ration the as prepared particles were purified by repeated precipitation of toluene dispersions with ethyl alco-hol three times and finally air dried for 12 h at 65°C. The XRD pattern of the solvothermally synthesized nanocrys-talline TiO2 powder (Figure 1) shows a pure tetragonal anatase phase with-out other titanium oxide polymorphs. The average crystallite size, calculated from XRD results using Scherer’s equa-tion, is found to be 4 nm. Comparing the line width of the reflexes provides no indication for an anisotropic growth of the TiO2 nanocrystals.

In contrast the XRD pattern of the na-norods (Figure 2), prepared in an open reaction vessel, shows a significant sharpening of the (004) peak com-pared to the other peaks because of an extended crystalline domain along the c-axis.

The fast growth along the [001] direc-tion is typical for the anatase phase [12,19,20] and results from the 1.4 times higher surface energy of the [001] surface compared to that of the [101] faces, as predicted by the Donnay-Harker rules [21]. The energy difference between the higher en-ergy surface and other lower energy surfaces can promote preferential growth along the [001] direction. Ban-field proposed another mechanism of rapid growth on [001] faces in which only the [001] surfaces can generate

ucts is prevented. Thus water, alcohol etc. are kept inside the system. Addi-tionally, the reaction temperature is increased above the boiling point of water or alcohol under normal pres-sure, thus the reactivity of the reac-tants might be enhanced. This causes large scale nucleation and fast crystal growth resulting in spheric nanoparti-cles. By the reaction in a closed auto-

Figure 2: X-ray diffraction pattern of TiO2 nanorods synthesized in an open reaction vessel. The obtained reflexes are consistent with those of known TiO2 anatase crystals (pdf-no.: 01-078-2486). A sharpening of the (004) peak is observable for the anatase nanorods because of the extended crystalline domain along the c-axis.

Figure 1: X-ray diffraction pattern of solvothermal synthesized TiO2 nanoparticles. The obtained reflexes are consistent with those of known TiO2 anatase crystal (pdf-no.: 01-078-2486). The calcu-lated particle size from the half width of the signals was 4 nm.

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Preparati on and characterizati on of polymer fi lms containing anatase na-noparti cles

The as prepared nanoparti cles and na-norods have been subjected to three dispersion/precipitati on steps. The re-sulti ng waxy precipitate can directly be dispersed by sti rring in an acrylic mono-mer mixture, containing 75 weight% HMA and 25 weight% HDDMA; resulti ng an opti cal clear light yellow dispersion. For subsequent UV curing and thermal post-curing photo initi ator I 184® and AIBN were added. Polymer fi lms were produced by applying this mixture with a doctor knife on glass microscope slides followed by UV curing and thermal post-curing. Aft er the curing processes the fi lms (20 µm thickness) remained trans-parent, indicati ng a homogeneous ag-glomerate free distributi on of parti cles in the polymer matrix. Figure 6 shows the distributi on of the TiO2 nanorods in such a polymer fi lm.

In TEM a homogeneous distributi on of parti cles in polymer matrix is visible and no agglomerati on of parti cles oc-curred. This result shows that the here-in presented parti cle synthesis can play an important role in nanocompos-ite fabricati on. The feasibility of insert-ing the parti cles in the acrylic system without any parti cle agglomerati on before polymerizati on leads to organic inorganic hybrid materials with very homogeneous parti cle distributi on.

Conclusion

The combinati on of a solvent functi on with surfactant properti es makes the OA/OAM mixture an eff ecti ve tool for producing quasi monodisperse and redispersable opti cal anatase nano-parti cles and nanorods. It was shown that the morphology of the obtained nanoparti cles can be controlled simply by changing the synthesis conditi ons

conti nuously reacti ve adsorpti on sites for the crystal growth because in this region the largest number of - O (or - OH) in appropriate positi ons exists to create an octahedral coordinati on en-vironment for Ti [22].

The size and morphology of the nano-parti cles and nanorods were analyzed using Transmission Electron Microscopy (TEM). For sample preparati on a parti -cle dispersion in toluene was cast onto a carbon coated TEM grid and the solvent was evaporated at room temperature, leaving the parti cles on the TEM grid. In all observed samples it is obvious, that the parti cle sizes are very well controlled and the size monodispersity is high.

The nanoparti cles shown in Figure 3 were prepared by the solvothermal synthesis in an autoclave. They are nearly monodisperse in a spherical morphology with a diameter of about 5 nm. The fact that the nanoparti cles have a well-defi ned interparti cle spac-ing is indicati ve of the encapsulati on of the nanocrystal cores by an organic coati ng.

TiO2 nanocrystals synthesized in an open reacti on vessel are shown in the TEM image in Figure 4. These parti cles consist of almost uniform nanorods with an average size of 4 nm (diameter) x 15 nm (length).

Dynamic light scatt ering techniques were used for studying the size and the size distributi on of nanoparti cles in liquids. UPA measurements of tolu-ene dispersions both of the nanoparti -cles and nanorods show a very narrow parti cle size distributi on and no signs of parti cle agglomerati on (Figure 5). For the nanospheres a hydrodynamic diameter of about 6.8 nm and for the rod shaped nanocrystals a diameter of about 8.8 nm can be found which represents an average value between longitudinal and transverse axis of the nanorod.

Figure 3: TEM image of solvothermally prepared TiO2 nanoparti cles (d ~ 5 nm).

Figure 4: TEM image of TiO2 nanorods, prepared in an open reacti on vessel (length: ~ 15 nm, width: ~ 4 nm).

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[6] Xiong L., Li J., Yu Y., Energies, 2009, 2, 1009-1030.[7] Zhu Y., Shi J., Zhang Z., Zhang C., Zhang X., Anal. Chem., 2002, 74, 120-124.[8] Camargo P.H.C., Satyanarayana K.G., Wypych F., Mater. Res., 2009, 12(1), 1-39.[9] Sun S., Zeng H., Robinson D.B., Raoux S., Rice P.M., Wang S., Li G., J. Am. Chem. Soc., 2004, 126, 273-279.[10] Chen M., Kim J., Liu J.P., Fan H., Sun S., J. Am. Chem. Soc., 2006, 128, 7132-7133.[11] Zhang Z., Zhong X., Liu S., Li D., Han M., Angew. Chem. Int. Edit., 2005, 44, 3466-3470.[12] Cozzoli P.D., Kornowski A., Weller H., J. Am. Chem. Soc., 2003, 125, 14539-14548.[13] Seo J.W., Jun Y.W., Ko S.J., Cheon J., J. Phys. Chem. B, 2005, 109(12), 5389-5391.[14] Jordan J., Jacob K.I., Tannenbaum R., Sharaf M.A., Jasiuk I., Mat. Sci. Eng. A, 2005, 393, 1-11.[15] Khaled S.M., Sui R., Charpentier P.A., Rizkalla A.S., Langmuir, 2007, 23(7), 3988-3995.[16] Yang F., Ou Y., Yu Z., J. Appl. Polym. Sci., 1998, 69(2), 355-361.[17] Sciancalepore C., Cassano T., Curri M.L., Mecerreyes D., Valentini A., Agostiano A., Tommasi R., Striccoli M., Nanotechnolo-gy, 2008, 19, 205705 (8p).[18] Jung M.W., Oh H.J., Yang J.C., Shul Y.G., B. Kor. Chem. Soc., 1999, 20(12), 1394-1398.[19] Zhang H., Banfield J.F., J. Mater. Chem., 1998, 8(9), 2073-2076.[20] Zhang H., Banfield J.F., J. Phys. Chem. B, 2000, 104, 3481-3487.[21] Donnay J.D.H., Harker D., Am. Mineral., 1937, 22(5), 446-466.[22] Lee Penn R., Banfield J.F., Geochim. Cosmochim. Ac., 1999, 63(10), 1549-1557.

using the analog reaction mixture. The nanoparticles are nearly monodis-perse in a spherical morphology with a diameter of about 5 nm. The obtained nanorods were almost uniform with an average size of 4 nm (diameter) x 15 nm (length) and they grew along the [001] direction. The organically capped nanoparticles and nanorods can be dispersed in liquid acrylic monomers. By a following polymerization of the mixture, an optimal embedding and agglomerate free distribution of the inorganic nanoparticles in the poly-mer matrix is reached. This fact makes these hybrid materials interesting in many fields of application with respect to their mechanical and optical proper-ties. A transfer to other inorganic na-noparticles and matrix systems is the subject of further investigations.

Acknowledgement

We would like to thank Dr. U. Werner and A. Haettich for TEM and R. Karos for XRD measurements.

References

[1] Fox M.A., Dulay M.T., Chem. Rev., 1993, 93, 341-357.[2] Sayılkan F., Erdemoğlu S., Asiltürk M., Akarsu M., Şener Ş., Sayılkan H., Erdemoğlu M., Arpaç E., Mater. Res. Bull., 2006, 41, 2276-2285.[3] Tachikawa T., Fujitsuka M., Majima T., J. Phys. Chem. C, 2007, 111(14), 5259-5275.[4] Sanchez C., Escutti M.J., van Heesch C., Bastiaansen C.W.M., Broer D.J., Loos J., Nussbaumer R., Adv. Funct. Mater., 2005, 15, 1623-1629.[5] Mont F.W., Kim J.K., Schubert M.F., Schu-bert E.F., Siegel R.W., J. Appl. Phys., 2008, 103(8), 083120 (6p).

Figure 5: Particle size distribution of TiO2 na-nospheres (A) (D10: 5.2 nm, D50: 6.8 nm, D90: 9.2 nm, volume distribution) and nanorods (B) (D10: 6.7 nm, D50: 8.8 nm, D90: 12.0 nm, vol-ume distribution) after three purification steps, dispersed in toluene.

Figure 6: TEM image of TiO2 nanorods (5 w%) embedded in HMA/HDDMA polymer film. The sample was prepared by cutting sections from the polymer film using a cryo-microtom.

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showed that adhesion initi ally increas-es with increasing preload and then plateaus for higher preloads. Gorb et al. [10] observed a drop in adhesion for fl at as well as structured polyvinyl-siloxane (PVS) pillars at high applied preload.

The gecko shows rapid att achment and detachment acti ons (milliseconds) during movement. Quick detachment from the att ached state is inherent to such a moti on. The ti lted setae, by a simple change of orientati on, can peel off easily from a surface [11-12]. While high adhesion strength has been obtained for arti fi cial pillar surfaces, it is sti ll a great challenge to mimic the specifi c gecko biomechanics of strong adhesion and easy release. A fi rst ex-ample using a shape memory polymer was developed by Reddy et al. [13]. It was shown that changing the orienta-ti on of micropillars from their verti cal to ti lted state results in a signifi cant loss of adhesion.

Here, we present a pressure actuated adhesive system that exploits the loss of inti mate contact by change of orien-tati on to tune adhesion. The adhesive system is composed of PDMS micropil-lars with aspect rati o 3 (length 30 µm and diameter 10 µm) fabricated using photolithography and moulding. We show that this system can reversibly switch between an adhesive and a non-adhesive state by applying low and high preload.

Experimental methods

Photolithography and soft moulding were used to fabricate micropillar ar-rays. The samples were characterized using scanning electron microscopy (SEM) and white light interferometry. The adhesion performance of the samples was measured by standard load-displacement tests on a home-built test apparatus, Microscopic Ad-

Abstract

We developed a dry syntheti c adhe-sive system inspired by gecko feet that can switch reversibly from adhesion to non-adhesion with applied pressure as external sti mulus. Micropatt erned polydimethylsiloxane (PDMS) surfaces with pillars of 30 µm length and 10 µm diameter were fabricated using photo-lithography and moulding. Adhesion properti es were determined with a fl at probe as a functi on of preload. For low and moderate applied compressive preloads, measured adhesion was 7.5 ti mes higher on the patt erned surfaces than on fl at controls whereas for high preloads adhesion dropped to very low values. In situ imaging showed that the increased preload caused the pillars to deform by bending and/or buckling and to lose their adhesive contact. The elasti city of PDMS aids the pillar recovery to the upright positi on upon removal of preload enabling repeata-bility of the switch. Such systems have promising properti es e.g. for industrial pick-and-carry operati ons.

Introducti on

Our previous work has demonstrated that splitti ng a contact into several small microscale contacts can explain strong gecko adhesion [1-2]. These ob-servati ons have led the way in design-ing pillar surface microstructures and fabricati ng syntheti c biomimeti c adhe-sives, e.g. [3-9]. As opposed to a single contact by an integral solid interface, a pillar-structured surface splits the contact formati on as well as detach-ment into multi ple events. The nature of these events in ti me depends on the geometry and orientati on of the pil-lars, elasti c moduli of pillars and probe and roughness of probe. Especially in-teresti ng for the present study is the eff ect of change of applied pressure or preload on the adhesion behavior of structured surfaces. Greiner et al. [6]

Bioinspired pressure actuated adhesive system

Dadhichi R. Paretkar, Marleen Kamperman, Andreas S. Schneider, Eduard Arzt, Functi onal Surfaces Group

18

a glass spring, at a constant velocity of 1 µm/s. The deflection of the glass spring during loading and unloading was monitored via laser interferome-try. A spring with a stiffness of 247 N/m was used and forces up to 0.1 N were measured with a resolution of 1 µN. Measurements were also performed with the probe tack tester at the PPMD labs, ESPCI, Paris (ESPCI tester). The ESPCI tester enabled in situ visualiza-tion of mechanical deformation of the PDMS micropillar array during adhe-sion testing. The translucent PDMS sample, mounted on a glass slide, was viewed using a long range microscope lens from the glass slide side, i.e. from the back of the sample. A polished flat steel probe with circular cross-section (6 mm diameter) was used to test ad-hesion. Additional experiments simu-lating the load-displacement adhesion test were performed using a microma-nipulator in SEM to obtain in situ high resolution pillar deformation images.

Results

Figure 1a shows the dependence of pull-off strength on the applied com-pressive preload stress for structured PDMS as well as for flat PDMS con-trol samples with curing conditions and dimensions similar to the struc-tured samples. Compared to control samples (maximum pull-off strength 8 kPa) the measured pull-off strengths of structured samples were about 7.5 times higher. At low compres-sive stresses (0.5 kPa), the measured pull-off strength values were also low (30 kPa). With an increase in com-pressive stress (> 3 kPa), the pull-off strength rapidly reached a maximum of 60 kPa. The pull-off strengths were retained at maximum for an interme-diate compressive stress range be-tween 3 and 123 kPa. Increasing the compressive stress further resulted in a sudden drop to extremely low pull-

hesion measurement Device (MAD) at INM, Saarbrücken. In a standard load-displacement test, the sample was loaded against and retracted from a flat glass probe with circular cross-section (1 mm diameter) mounted on

Figure 1: (a): Dependence of pull-off strength on applied preload stress for fibrillar and flat PDMS surfaces measured with MAD. Adhesion state with high pull-off strength and non-adhesion state with low pull-off strength can be distinguished. Flat controls show maximum pull-off strengths of 8 kPa. (b): Repeatability of switching between adhesive and non-adhesive state measured with MAD. Pull-off strength for 50 different adhesion trials wherein alternating high and low preload stresses were applied.

19

top face contact with the probe. Dur-ing unloading, the pillars regain their original upright positi on and parti ally reform contact to the probe.

Discussion

In this study, we fabricated micropat-terned PDMS surfaces, which can be switched from a state of adhesion to non-adhesion by changing the applied preload. The low pull-off strength (28.6 kPa) at low preload indicates that a certain minimum compressive preload is necessary to form inti mate contact with the probe. A minimum compressive stress of 3.5 kPa is re-quired for achieving the plateau pull-off strength of 60 kPa. The adhesion remains almost constant for further in-

off strengths (1.2 kPa). Thus, two dis-ti nct states, that of adhesion (high Pc)and that of non-adhesion (very low Pc) were realized by a change of preload stress. The repeatability of the actu-ated system was tested over many cycles using alternati ng low and high preloads and measuring the resulti ng adhesion. A selecti on of 50 cycles is shown in Figure 1b. Pull-off strengths of 60 kPa for the adhesive state and below 0.5 kPa for the non-adhesive state were recorded. Thus, the actu-ated adhesion system is reversible as well as repeatable over several cycles.

Figure 2 shows a representati ve force-ti me plot for an adhesion test at high preload of 5 N (177 kPa). Aft er contact formati on and lateral displacement of the pillar tops with respect to their bott oms (inset I), a rapidly propagat-ing wave corresponding to the fl ipping of pillars from top contact to the side seems to occur. This is synchronous with a jump in the measured force at around 1.15 ± 0.05 N. Ins ets II and III show pillars lying fl at aft er the fl ip. At even higher loads, the fl ipped pillars are seen fl att ened against the PDMS surface of the backing layer and touch-ing neighboring pillars (inset IV). Dur-ing unloading the pictures suggest that the pillars fl ip up again and show only lateral displacement with respect to their bott oms (inset V). The subse-quent peel-off wave is observed to proceed much faster in comparison to that of the low preload case (inset VI).

Side view images of the loading-un-loading process were obtained by ad-hesion experiments in the SEM. A fl at Si probe (smooth side of a wafer) is brought in contact with the PDMS pil-lar array using a micromanipulator. The fi rst three images from the left in Fig-ure 3 show the loading and the picture in the right the unloading of the experi-ment. Aft er contact formati on the pil-lars bend in one directi on, losing the

Figure 2: Force – displacement curves and top-view in situ videos for 5N preload. I: laterally dis-placed pillar tops, II: pillars fl ipped aft er jump in force (~ 1.18 N), III and IV: pillars lying fl at on PDMS backing, V: apparent recovery from fl ip during retracti on and VI: detachment with peel wave, direc-ti on indicated by arrow.

20

High preload causes the pillars to flip at forces of 1.15 ± 0.05 N. This is re-lated to a sudden transition from top contact to side contact of the pillar as optically observed and is accompanied by a jump in the force time curve. The ‘jump’ can be due to slip of the adhe-sive contact and/or buckling of the pil-lars. It is expected that the aspect ratio of the pillar and roughness of probe will play a significant role in decid-ing between these two mechanisms. For example, a low aspect ratio pillar is highly resistant to buckling and is more likely to slip before it can buckle, whereas a high aspect ratio pillar will buckle before it slips from top contact. For an intermediate aspect ratio, there will be a competition between the two events.

During probe retraction for measure-ments applying a high preload of 5 N the pillars flip up and appear to regain partial top surface contact shortly be-fore the compressive shear stresses are completely relieved (see also Fig-ure 3). Low pull-off forces are meas-ured because there is no intimate con-tact formed between the pillar top and the probe during retraction. The flip-ping of the pillars is not critical for the reversibility of the system as indicated in Figure 1b.

Conclusion and outlook

• PDMS micropillars with AR 3 were tested for normal adhesion perfor-mance using standard load-displace-ment tests. Pull-off forces of 7.5 times higher than those of flat PDMS under the same test conditions were recorded.

• Samples were tested for switch- ability in adhesion performance by changing the applied preload. Two preload-defined states of adhesi-on and non-adhesion were found. For applied stresses between 3 and

crease in preload suggesting that there is no further increase in real contact area. For preload stresses larger than 120.9 ± 2.2 kPa, however, the sample shows a loss in adhesion with average pull-off strength as low as 1.2 ± 1.1 kPa.

The in situ videos from the ESPCI tester show that contact formation proceeds in wave form starting from the circum-ference of the probe. This suggests that the sample was slightly misaligned dur-ing the experiment. From the speed of the propagating wave, the misalignment can be estimated to be 0.2°. As the sys-tem alignment was optimized prior to the test, there are two other reasons which could explain this observation. The 6 mm diameter flat steel probe has a roughness with wavelengths much larg-er than the diameter of the pillars giving rise to topography effects. Secondly the PDMS sample itself is not perfectly flat. Due to this, the pillars are not exactly normal to the probe which may induce an additional shear component to the applied normal compressive forces. Consequently pillar deformation occurs under compressive shear, which may be responsible for the observed lateral dis-placement of the top of the pillars with respect to their bottoms. The direction of the lateral displacement seems to be dictated by the misalignment. Detach-ment proceeds as a peel wave in the direction opposite to that of the contact formation with the crack usually initi-ated at the edge of the circular contact interface between probe and sample.

Figure 3: Side-view observations of pillars in SEM. Sequence from in situ load-displacement experi-ments simulating an adhesion test at high preload. The first three images from the left are during loading and the picture to the right during unloading.

21

References

[1] E. Arzt, S. Gorb, R. Spolenak, P. Natl. Acad. Sci. U. S. A. 100 (2003) 10603-10606.[2] E. Arzt, S. Enders, S. Gorb, Z. Metallkd. 93 (2002) 345-351.[3] A.K. Geim, S.V. Dubonos, I.V. Grigorieva, K.S. Novoselov, A.A. Zhukov, S.Y. Shapoval, Nat. Mater. 2 (2003) 461-463.[4] M. Sitti , R.S. Fearing, J. Adhes. Sci. Technol. 17 (2003) 1055-1073.[5] B. Schubert, C. Majidi, R.E. Groff , S. Baek, B. Bush, R. Maboudian, R.S. Fearing, J. Adhes. Sci. Technol. 21 (2007) 1297-1315.[6] C. Greiner, A. del Campo, E. Arzt, Lang-muir 23 (2007) 3495-3502.[7] A. del Campo, C. Greiner, E. Arzt, Lang-muir 23 (2007) 10235-10243.[8] H.E. Jeong, K.Y. Suh, Nano Today 4 (2009) 335-346.[9] L.F. Boesel, C. Greiner, E. Arzt, A. del Campo, Adv. Mater. 22 (2010) 2125-2137.[10] A. Peressadko, S. Gorb, J. Adhesion 80 (2004) 247-261.[11] K. Autumn, A. Ditt more, D. Santos, M. Spenko, M. Cutkosky, J. Exp. Biol. 209 (2006) 3569-3579.[12] Y. Tian, N. Pesika, H. Zeng, K. Rosen-berg, B. Zhao, P. McGuiggan, K. Autumn, J. Israelachvili, P. Natl. Acad. Sci. U. S. A. 103 (2006) 19320-19325.[13] S. Reddy, E. Arzt, A. del Campo, Adv. Mater. 19 (2007) 3833-3837.

125 kPa, an adhesion maximum of 60 kPa is realized, whereas for pre-loads larger than 125 kPa very low adhesion strengths of 1.2 kPa are recorded.

• The repeatability of the on-off states was tested for 50 cycles. Full switch-ability from adhesive to non-adhesi-ve state by change in applied preload was found.

• We presented a qualitati ve under-standing of the actuated adhesive system based on in situ videos and SEM studies of adhesion tests. The actuati on mechanism mimics that of the gecko adhesive system in that the change of orientati on of the mi-cropillars is responsible for loss in adhesion. Inti mate contact at pull-off from low applied preload leads to high adhesion. Loss of contact during high applied preload leads to lack of inti mate contact reformati on during pull-off resulti ng in loss of adhesion.

22

als to serve as a source for new man-made materials will be investigated. We also hope to understand biological control principles from the viewpoint of mechanosensing. This means – in contrast to Wolff [5] – to understand how a cell or tissue translates the na-noscale properties of a material while it is formed, into a genetic program. This program guarantees hierarchical function on a much larger scale, which is relevant for the survival of the whole organism. Hierarchical shell formation in mollusks is likely to be controlled on the molecular and cellular scale, for example via transmembrane myosin-chitin synthases [6]. The enzyme may or may not be in direct contact with the forming mineralized material.

Atoms, Ions and Biopolymers

Our goal is to understand how animals produce materials that are precisely formed on the molecular scale and function precisely on the macroscopic scale. For example, nacre or mother-of-pearl consists of regularly shaped micron-sized platelets of mineral crys-tals aligned along their crystallograph-ic axes [7]. In fact, the hierarchical architecture of mineralized platelets separated by organic nano-layers is a prerequisite for remarkable materials properties such as fracture toughness [8]. However, little is known regarding the molecular bonds that hold this ma-terial together [9]. The basic inorganic building blocks of biominerals are metal ions such as Ca2+ and Mg2+, and anions such as carbonate and phos-phate. In order to accommodate the brittleness of the mineral phase, the size and anisotropy of mineral particles is under species-specific control [10]. The basic organic building blocks are biopolymers such as carbohydrates and proteins [11]. The latter are mainly characterized by covalent backbones with covalently attached side-chains.

Abstract

This article investigates nacre and pea-cock feather rachis from a molecular and structural point of view, in addi-tion to unifying principles in nature that may control hierarchical func-tions. This biological material serves as an example for deciphering basic prin-ciples in nature that may subsequently be used to design new artificial materi-als and structures.

Introduction

The properties of materials determine how useful they can be in technologi-cal applications. Currently, there is a trend towards replacing some man-made materials by natural, biogenic materials, by definition called “biologi-cal materials” [1]. On the other hand, new man-made materials are being developed based on concepts copied directly from nature. The first issue is to decipher the basic principles of how a given biological material fulfils its function and then secondly, to de-termine which chemical and structural features are necessary to translate an advantage in nature into a technologi-cal one. Biological materials fulfil differ-ent “materials design criteria” [2], the most prominent example is the com-bination of stiffness and strength with low density. Typical biological materi-als are not only compact but also form foamy materials [3] and composite structures [4]. The composite can com-prise one and the same material (com-pact – foam, crystalline – amorphous), or a combination of phases from dif-ferent material classes (e.g. polymers, minerals). Another observation is that naturally formed materials are often a product of structural as well as chemi-cal gradients. The aim of the present paper is to provide an overview of the exclusive features of biological materi-als. The potential of biological materi-

Biological Materials – Bioinspiration on Different Length Scales

Ingrid M. Weiss, Biomineralization Group

Figure 1: Examples for biological materials: The mollusk shell and the peacock’s train. Both are composite materials that serve as mechanical support. Top: Nacreous part of Haliotis spec., © Photo courtesy of INM (Uwe Bellhäuser 2008 http://www.dasbilderwerk.de/; Ingrid Weiss 2011). Bottom: Pavo cristatus mut. alba in the Beacon Hill Children’s Farm Victoria, BC on April 17, 2005. Source: http://en.wikipedia.org. © Photo courtesy of Darren Stone/ Victoria Times Colonist licensed under the Creative Commons Attribution-Share Alike 2.0 Generic (http://crea-tivecommons.org/licenses/by-sa/2.0/deed.en) license.

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The molecular structure of F-kerati n is not listed in the 3D database. However the current model based on recent X-ray data suggests that the fi bre crystals are deposited fi rst as a loose assembly, which obtains a fi nal dense packing only outside the feather follicle [20]. Feather follicles are an arrangement of cells from where the feathers are pro-duced. Inside the feather follicle, cells deposit the F-kerati n in the cytoplasm [21]. The formati on of feathers is abso-lutely remarkable because the crystal-lizing F-kerati n forms fi rst some sort of intracellular compartment, “fi laments within a matrix” [22], which may pass through the cytoplasmic membrane at some stage and “melt” with the F-kerati n produced by other cells of the follicle. It should be possible to obtain an approximate value for the driving force for the phase separati on of F-kerati n and assembly into either the compact cortex or the foamy medulla. Plasti city follows a law of thermal acti -vati on. For the cortex, we obtained an acti vati on enthalpy of 1.75 eV and an acti vati on volume of 0.83 nm3 [17,23].

The primary signature of these side-chains subsequently determines steric, hydrophobic and H-bond stabilized in-tramolecular secondary structures as well as additi onal intermolecular ionic interacti ons, including mineral forma-ti on.

The plasti city of bone is a result of the molecular architecture of collagen, which is a triple helix built from helical polypepti des, though these would not form the commonly known a-helix [12]. A comparison between macroscopic and nanoscopic stress-strain analyses showed that the ability of bone ti ssue to accommodate deformati on is mainly due to organic fi bres such as collagen in a matrix [13,14]. The purpose of the min-eral nanoparti cles (hydroxyapati te in the case of bone) located between the colla-gen fi bres is to strengthen the material. It has been demonstrated by thermal ac-ti vati on analyses that the criti cal bonds are electrostati c in nature [15].

From Assembly to Cohesion: F-Kerati n

Peacock feathers are about one meter long and exhibit great uniformity and consistent quality. The microstructure and mechanical properti es are surpris-ingly uniform along the feathers. The level of precision for forming the mate-rial is comparable to nacre formati on. Once per year, the peacock grows a new set of tail feathers at a synthesis rate of up to 10 mm/day. The feather rachis has been identi fi ed as a true composite structure [18]. It is a long slender beam with a compact conical cortex shell that surrounds a low den-sity medulla core. Both the compact shell and the low density foam are made of F-kerati n. The F-kerati n cor-tex is a remarkable material combining extreme fl exural rigidity and high frac-ture toughness, which makes it appeal-ing for applicati ons in quill embroidery [19].

Figure 2: The relati ve strengths of inter-molecular interacti ons (weak and strong bonds), with acti -vati on energies in diff erent units: eV, kJ/mol, and kcal/mol. Aft er [16]. Data for alpha-collagen and F-kerati n according to [15,17].

24

matic control [6], which happens at the microstructured interface between the cell and the extracellular matrix – a sort of “material”. It subsequently so-lidifies into a composite ceramics. The chitin itself is likely to accommodate aragonite inducing protein complex-es [29]. It can be speculated how the feedback between the cells and the forming material happens. Currently, we do not know exactly how this feed-back is encoded in the genome of the biomineralizing species [30]. Cell adhe-sion and mechanosensing is one way of trying to understand the precise formation of materials in biology [31]. Developmental processes likely inter-fere with microstructured materials as demonstrated recently using Dictyos-telium as a model system [32].

Perspectives

Peacock feathers are interesting as they form a very simple mechanical ar-rangement subjected to simple gravity loading. Elementary beam theory can explain stress and strain everywhere in the feather, up to the follicle where they are attached to the body. This simplicity allows an understanding of the mechanical influence on growth and form, unlike in flying birds where the feathers undergo complicated loading histories.

Our interest in comparing the non-mineralized peacock’s feathers with mineralized nacre stems from the de-sire to understand biological forma-tion of hierarchical materials from the viewpoint of mechanosensing. Sea shells, which we commonly iden-tify according to their macroscopic appearance, form in mollusks under molecular control, for example via transmembrane myosin-chitin syn-thases. Of course, there is substantial cross-talk with developmental genes. Also in the bird’s feather follicle, cel-

As illustrated in Figure 2, these values are far from H-bonds (25meV) and suggest that breaking and formation of electrostatic bonds is responsible for the ability of this non-mineralized material, consisting of only one, almost pure protein species, to accommodate plastic deformation.

Macroscopic Function: A Forming, Mineralizing Interface

A complex cellular differentiation pro-cess produces bird feathers, a com-posite material (compact and foamy rachis) made of one predominant pro-tein species: F-keratin. Nacre, in con-trast, has an extraordinary complex chemical composition and nanostruc-ture [24]. The biogenic compounds originate from cells. In contrast to 3D feather follicles, the 2D mantle epithe-lia of mollusks represent an archetype of multicellular arrangements [25]. Compartmentalization occurs within lipid membrane vesicles, which de-posit their contents under strict cellu-lar control in the extracellular space by exocytosis. In addition, some low-mo-lecular weight compounds and mineral ions in particular can be translocated through the cytoplasmic membrane via transmembrane protein channels [26]. One particularly interesting trans-port process is the deposition of chitin in the extracellular space. In the final mollusk shell product, chitin is one of the abundant organic compounds [27]. The arrangement of chitin geometries differs as a function of developmental stage and shell ultrastructure [28]. The origin of β-chitin is intracellular, and the precursor molecules (UDP-GlcNAc) are synthesized in the cytoplasm, like the precursors of the insoluble F-ker-atin. The solubility of GlcNAc polymers decreases with increasing polymer length. The assembly into high-molec-ular weight chitin is under tight enzy-

25

[7] Heiland, B., Schneider, A.S., Arzt, E. and Weiss, I.M. (2010) Skalenübergrei-fende Strukturanalyse an Anschliff en und Dünnschliff en von Seeohr-Schalen. In Fortschritt e in der Metallographie - Vor-tragstexte der 13. Internati onalen Me-tallographie-Tagung, 29. September - 01. Oktober 2010 in Leoben (Kneissl, A. and Clemens, H., ed.), pp. 121-126. Werkstoff -Informati onsgesellschaft mbH, Frankfurt, Germany.[8] Gao, H., Ji, B., Jäger, I.L., Arzt, E. and Fratzl, P. (2003). Materials become insen-siti ve to fl aws at nanoscale: Lessons from nature. Proc. Natl. Acad. Sci. U.S.A. 100, 5597-5600.[9] Smith, B.L. et al. (1999). Molecular mechanisti c origin of the toughness of natural adhesives, fi bres and composites. Nature 399, 761-763.[10] Taylor, J.D., Kennedy, W.J. and Hall, A. (1973). The shell structure and mineral-ogy of the bivalvia. Bull. Br. Mus. Nat. Hist. (Zool.) 22, 253-294.[11] Sigel, A., Sigel, H. and Sigel, R.K.O. (2008) Biomineralizati on: From Nature to Applicati on. In Met. Ions Life Sci. - Biomin-eralizati on: From Nature to Applicati on (Sigel, A., Sigel, H. and Sigel, R.K.O., ed.). John Wiley & Sons, West Sussex, UK.

lular diff erenti ati on processes occur, and we are sti ll far from understand-ing all the molecular details that lead from one parti cular F-kerati n gene to a true composite material: a feather rachis of remarkable molecular and geometric simplicity. Even details such as the self-assembly of F-kerati n and β-chiti n into fi bers, the homogeneity of F-kerati n along the rachis and, in mollusk shells, the complementarity of β-chiti n and mineral orientati on pro-vide molecular bioinspirati on for new man-made materials. So far, thermal acti vati on analysis provided important insight into the plasti city of F-kerati n. In terms of evoluti on, we note a gap of ~4x108 years between the fi rst appear-ance of F-kerati n and nacre, which ex-ists since less than ~6x108 years ago. In the future, we will address more fun-damental aspects that may explain the properti es and evoluti on of these two high-performance materials.

References

[1] Reis, R.L., Weiner, S. and Fratzl, P. (2005) Hierarchical Structure and Mechan-ical Adaptati on of Biological Materials. In Learning from Nature How to Design New Implantable Biomaterials: From Biominer-alizati on Fundamentals to Biomimeti c Ma-terials and Processing Routes), pp. 15-34. Springer Netherlands.[2] Ashby, M.F. (2007) Materials Selecti on in Mechanical Design, Elsevier-Spektrum Akademischer Verlag. Munich, Germany.[3] Gibson, L.J. and Ashby, M.F. (1997) Cellular Solids: Structure and Properti es, Cambridge Univ. Press. Cambridge.[4] Ashby, M.F. (2008) The CES EduPack Database of Natural and Man-Made Mate-rials. In Granta Material Inspirati on - Bio-engineering. Granta Design, Cambridge, U.K.[5] Wolff , J. (1892) Das Gesetz der Trans-formati on der Knochen, Hirschwald. Ber-lin.[6] Weiss, I.M., Schönitzer, V., Eichner, N. and Sumper, M. (2006). The chiti n syn-thase involved in marine bivalve mollusk shell formati on contains a myosin domain. FEBS Lett 580, 1846-1852.

Figure 3: Scheme for the evoluti on of nacre vs. feather on a logarithmic ti me scale (Unit [Ma]: mil-lion years before present). Mollusk shells are chemically and structurally complex multi -component systems. Feathers consist mainly of F-kerati n and therefore represent chemically, but not struc-turally, a one-component system. Intracellular communicati on (signal transducti on) may suffi ce to explain basic aspects of mollusk shell formati on. The biosynthesis of feathers requires sophisti cated communicati on between cells (developmental biology). This may be one possible reason for the extraordinary delay in the evoluti on of feathers as compared to mollusk shells.

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[23] Weiss, I.M. and Kirchner, H.O.K. (2011). Plasticity of two structural proteins: Al-pha-collagen and beta-keratin. Journal of the Mechanical Behavior of Biomedical Materials In Press, Accepted Manuscript, doi:10.1016/j.jmbbm.2011.02.008.[24] Addadi, L., Joester, D., Nudelman, F. and Weiner, S. (2006). Mollusk shell for-mation: A source of new concepts for un-derstanding biomineralization processes. Chemistry - A European Journal 12, 980-987.[25] Bevelander, G. and Nakahara, H. (1969). An electron microscope study of the formation of the nacreous layer in the shell of certain bivalve molluscs. Calcif. Tissue Res. 3, 84-92.[26] Weiss, I.M. and Marin, F. (2008) The Role of Enzymes in Biomineralization Pro-cesses. In Met. Ions Life Sci. - Biominerali-zation: From Nature to Application (Sigel, A., Sigel, H. and Sigel, R.K.O., ed.), pp. 71-126. John Wiley & Sons, West Sussex, UK.[27] Nudelman, F., Chen, H.H., Goldberg, H.A., Weiner, S. and Addadi, L. (2007). Spiers Memorial Lecture Lessons from biomineralization: comparing the growth strategies of mollusc shell prismatic and nacreous layers in Atrina rigida. Faraday Discussions 136, 9-25.[28] Schönitzer, V. and Weiss, I.M. (2007). The structure of mollusc larval shells formed in the presence of the chitin syn-thase inhibitor Nikkomycin Z. BMC Struct Biol 7, 71.[29] Suzuki, M., Saruwatari, K., Kogure, T., Yamamoto, Y., Nishimura, T., Kato, T. and Nagasawa, H. (2009). An acidic matrix pro-tein, Pif, is a key macromolecule for nacre formation. Science 325, 1388-1390.[30] Weiss, I.M. (2010). Jewels in the Pearl. ChemBioChem 11, 297-300.[31] Sackmann, E. and Merkel, R. (2010) Lehrbuch der Biophysik, Wiley-VCH. Berlin.[32] Eder, M., Concors, N., Arzt, E. and Weiss, I.M. (2010). Micropatterned Poly-mer Surfaces and Cellular Response of Dictyostelium. Advanced Engineering Ma-terials 12, 405-411.

[12] Nelson, D.L. and Cox, M.M. (2005) Lehninger Principles of Biochemistry, W.H. Freeman & Co.[13] Gupta, H.S., Seto, J., Wagermaier, W., Zaslansky, P., Boesecke, P. and Fratzl, P. (2006). Cooperative deformation of mineral and collagen in bone at the na-noscale. Proc. Natl. Acad. Sci. U.S.A. 103, 17741-17746.[14] Fratzl, P. and Weinkamer, R. (2007). Nature‘s hierarchical materials. Progress in Materials Science 52, 1263-1334.[15] Gupta, H.S., Fratzl, P., Kerschnitzki, M., Benecke, G., Wagermaier, W. and Kirchner, H.O.K. (2007). Evidence for an elementary process in bone plasticity with an activa-tion enthalpy of 1 eV. J. R. Soc. Interface 4, 277-282.[16] Vincent, J.F.V. (1990) Structural Bio-materials, Fig. 2.7, Princeton Univ. Press. Princeton, New Jersey.[17] Weiss, I.M., Schmitt, K.P. and Kirchner, H.O.K. (2011). The peacock‘s train (Pavo cristatus and Pavo cristatus mut. alba) II. The molecular parameters of feather kera-tin plasticity. J. Exp. Zool. in print.[18] Weiss, I.M. and Kirchner, H.O.K. (2010). The peacock‘s train (Pavo crista-tus and Pavo cristatus mut. alba) I. struc-ture, mechanics, and chemistry of the tail feather coverts. Journal of Experimental Zoology Part A: Ecological Genetics and Physiology 313A, 690-703.[19] Weiss, I.M. and Kirchner, H.O.K. (2010). Quill Embroidery: A Case Study in the Mechanics of Biological Materials. Ad-vanced Engineering Materials 12, 412-416.[20] Pabisch, S., Puchegger, S., Kirchner, H.O.K., Weiss, I.M. and Peterlik, H. (2010). Keratin homogeneity in the tail feathers of Pavo cristatus and Pavo cristatus mut. alba. Journal of Structural Biology 172, 270-275.[21] Filshie, B.K. and Rogers, G.E. (1962). An electron microscope study of the fine structure of feather keratin. J. Cell Biol. 13, 1-12.[22] Fraser, R.D.B. and Parry, D.A.D. (2008). Molecular packing in the feather keratin filament. Journal of Structural Biol-ogy 162, 1-13.

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the ceramic phase, but was modifi ed by the surface topography. When com-pared to microscaled ceramic materials, nanoceramics have an increased num-ber of atoms and crystal grains at their surfaces and possess a higher surface area to volume rati o. It has been shown that the cumulati ve adsorpti on of pro-teins from body fl uids is signifi cantly higher on smaller, nanometer grain sized materials [8]. Webster et al. corre-lated enhanced vitronecti n adsorpti on, conformati onal changes and bioacti vity to the increased osteoblast adhesion on nanostructured alumina [9]. Such fi nd-ings indicate that nanostructures also aff ect the cellular acti viti es rather than only simply enhancing the surface at-tachment.

On the other hand, it is known that several cellular processes, such as ad-hesion, proliferati on, migrati on, diff er-enti ati on and changes in cell shape, are infl uenced by the Extracellular Matrix (ECM), which is not only composed of nanostructured features. The ECM con-sists of various structures at diff erent length scales. For example, specifi cally for the bone, hydroxyapati te platelets are between 2 and 5 nm in width and 50 nm in length, whereas Type I colla-gen fi bers are a triple helix of 300 nm in length, 0.5 nm in width and have a periodicity of 67 nm [10]. Besides these nanoscaled structures, microscaled features such as macrophages are also found in the ECM. In this context, 3D arti fi cial structures mainly composed of fi brous structures, but also accom-modati ng pores for larger, microscaled features may be of interest for studying cell-surface interacti ons.

In the current study, we introduce a new approach to prepare nano- to micro-structured alumina surfaces by combining chemical vapor depo-siti on (CVD) and pulsed laser treat-ment. We synthesized Al/Al2O3 bipha-sic nanowires by the decompositi on of

Introducti on

Cells exhibit highly sensiti ve interac-ti ons with the surrounding chemical and topographical environment [1]. Surface topography with a defi nite chemistry has been shown to signifi -cantly aff ect cell adhesion, orienta-ti on, cell acti vati on and migrati on [2], but the mechanisms mediati ng such cell responses sti ll remain unclear. It is an ongoing discussion whether the chemical patt erning of the surface is also altered when the topography of the surface is modifi ed. Sherlock et al. demonstrated an improvement of cell adhesion on laser structured polymer surfaces [3]. Similarly, Yu et al. showed alignment of cells on polymer sur-faces patt erned by laser interference lithography [4]. In such approaches, it is not clear whether the altered sur-face chemistry or physical patt erning infl uenced the cell interacti on with the surface.

In comparison to polymers, ceramics off er bett er stability in terms of surface chemistry. Alumina has been used as implant material since the early 1970s due to its excellent biocompati bility, corrosion resistance and phase stabil-ity [5]. In additi on, superior mechanical properti es of alumina including high hardness, wear resistance, scratch re-sistance, low coeffi cient of fricti on and suffi cient mechanical strength to resist fati gue make it one of the strongest candidates for implant applicati ons among the ceramics [6].

Besides its biocompati bility, the surface topography also plays a crucial role in the performance of alumina implants. In-vitro studies provided evidence of increased osteoblast (bone-forming cell) adhesion on nanophase alumina (e.g. grain sizes less than 100 nm) com-pared to larger conventi onal grain size alumina [7]. Such studies demonstrated that enhanced osteoblast adhesion was independent of surface chemistry and

Micro-/nanostructured alumina as model surface to study topography eff ects on cell-surface interacti ons

Cenk Aktas, Marina Marti nez Miró, Juseok Lee, Stefan Brück,Michael Veith, CVD/Biosurfaces Group

28

composition. Depending on the inte-gral laser energy and thus the com-pletion of the oxidation of the Al core, the chemical composition can vary be-tween Al1.0·Al2O3 and Al0.0·Al2O3, which always results in an identical shell. In both cases, Al2O3 is the outer chemical compound, which may be responsible for the interaction with cells.

Experimental

Al/Al2O3 bi-phasic nanowires were de-posited by the decomposition of the single source molecular precursor (tBuOAlH2)2 on heated metallic sub-strates under a reduced pressures of 2-5x10-2 mbar. Prior to the deposition, the precursor compound (tBuOAlH2)2 was synthesized following the routes described elsewhere [11] under dry N2 using standard Schlenk techniques.

For laser treatment, we used an Nd:YAG laser which generates laser pulses of 4 to 8 ns, with a maximum pulse energy of 2000 mJ, at a repeti-tion rate of 10 Hz and a fundamental wavelength of 1064 nm. By frequency doubling, a wavelength of 532 nm with maximum pulse energy of 1000 mJ (with a spot size of 8mm) was used for texturing of the deposited layers due to their strong absorption covering UV to NIR wavelengths. The number of laser shots, N, was controlled with an electromechanical shutter. The surface structuring was studied by applying different laser fluencies and numbers of pulses, N.

As-deposited and laser treated sam-ples were visualized by means of SEM (FEI Quanta 400 FEG) at an accelerating voltage of 10 kV. The crystal structure was examined by Raman spectroscopy (Labview Aramis Raman microspec-trometer, Horiba Jobin Yvon). The sur-face composition was analyzed using a PHI 5600 XPS employing monochro-matic Al Kα X-rays.

(tBuOAlH2)2 on metal, silicon and glass substrates at 600°C. Heat treatment of the Al/Al2O3-nanowires by a high en-ergy nanosecond pulsed laser leads to melting and oxidation of the Al-core. The laser treatment produces a large variety of micro- and nanostructured Al2O3 surfaces with identical chemical

Figure 1: SEM images of deposited nanowires at (a) low magnification and (b) high magnification.

Figure 2: SEM images of the deposited layers after (a) 1 laser pulse, (b) 2 laser pulses, (c) 4 laser pulses and (d) 8 laser pulses.

29

layers aft er repeated high energy puls-es. Higher magnifi cati on SEM micro-graphs, given in Figure 3, show more hints on the pulsed laser modifi cati on of deposited layers.

When the laser fl uency is increased to F=0.3 J/cm2, nanopores and spherical nanoprotrusions with diameters of 60-90 nm form aft er a single laser pulse. The examinati on of the SEM images (Figure 3a and b) suggests the follow-ing mechanism for the formati on of such nanopores and spherical nano-protrusions: The nanopores are always accompanied by nearby nanoprotru-sions, indicati ng a nano-scaled mate-rial transport to an adjacent site. It can be envisioned that a high temperature gradient induces a radial surface ten-sion gradient which expels the spheri-cal liquid droplets to the periphery of the molten material. This may be the reason for the formati on of spherical nanostructures upon solidifi cati on.

It has been shown that the molten Al core oxidizes to Al2O3 aft er CW laser treatment and XRD analysis clearly showed the formati on α-alumina, as demonstrated before [13]. On the other hand, short laser pulses can only heat a thin layer near the sur-face. Since a local phase analysis is needed on the surface, micro Raman spectroscopy was performed. Figure

Results and Discussion

Figure 1a and 1b show SEM images of randomly grown Al/Al2O3-nanowires on metallic substrates at 600 °C. Recently, we have shown that such bi-phasic nanowires have uniform diameters of about 20-30 nm and are composed of an inner Al-core that is wrapped up by an Al2O3-shell at a constant molar rati o of Al/Al2O3 = 1:1 [12].

Figure 2 displays SEM images of the surface topography produced by na-nosecond laser processing at the near-damage-threshold fl uency of F=0.2 J/cm2 for diff erent numbers of laser pulses. The main features are random nanopores, nanoprotrusions or micro-nano hillocks. Aft er a single laser pulse, the extreme temperature increase in-duces a local surface melti ng, as can be seen in Figure 2a. The regions on the surface which are covered with rela-ti vely dense and highly interpenetrat-ed nanowires exhibit stronger opti cal absorpti on. These regions seem to be parti ally molten and the molten mate-rial has fl own over the surface. Micro-grooves and protrusions form due to the fast solidifi cati on of the expelled liquid on the boundary of the solid state material. The change in the color of the deposited layers from black to white (not shown here) also shows similariti es to the transformati on of the Al/Al2O3 composite to Al2O3 which is similar to our previous observati ons in case of CW laser treatment [13].

The second laser pulse creates a rela-ti vely smooth surface due to re-melt-ing of the layer, as is shown in Figure 2b. The surface becomes smoother af-ter four laser pulses, but it seems likely that repeated thermal shocks create cracks on the surface (Figure 2c). Aft er eight pulses delaminati on of the fi lm was observed. This is an indicati on of extremely high thermal shocks. Li et al. [14] and Guo et al. [15] showed similar deformati ons and delaminati on of the

Figure 3a and 3b: SEM images of the deposited layers aft er a single laser pulse.

30

Figure 5a and 5b show the XPS spectra of the Al/Al2O3 layer before and after a single laser pulse. The peaks originate from the ejection of Al 2p, Al 2s, O 1s and C 1s core electrons. In addition, the O (KLL) Auger signals can be easily identified. XPS analysis indicates that the chemical composition of the sur-face shows no drastic change after the laser treatment. The low carbon con-tent seems to be accumulated during the sample-handling.

Conclusion

Irradiation of deposited nanowires by nanosecond laser pulses in air leads to a melting and oxidation of the Al-core to Al2O3. Pulsed laser treatment produced a large variety of micro-structures and nanostructures. Such a combination of nano- and microscaled features is important to study cell–surface interactions since the ECM is made of multi-scale features. After repeated laser pulses, a formation of sphere-like microstructures was ob-served. Besides the variety of surface structures, the chemical state remains identical in each case. Such surfaces are suitable to perform cell culture ex-periments, revealing a clear influence of the nano- and microtopography on the cell adhesion and proliferation.

References

[1] R. Singhvi, G. Stephanopoulos, D. I. C. Wang; Biotechnol. Bioeng. Mater. 43 (1994), 764.[2] A. Curtis, C. Wilkinson; Biomaterials 18, 24 (1997).[3] R. J. Sherlock, D. N. Bhogal, M. Ball, T. J. Glynn; Proc. of SPIE Vol. 4876.[4] F. Yu, F. Mücklich, P. Li, H. Shen, S. Mathur, C.-M Lehr, U. Bakowsky; Biomac-romolecules 6 (2005) 1160-1167.[5] D. L. Wise, D. J. Trantolo, D. E. Altobelli, M. J. Yaszemski, J. D. Gresser; Human Bio-materials Applications, Humana Press, Totowa, New Jersey (1996).

4 shows the Raman spectra of layers treated with different numbers of laser pulses. For comparison, a reference sapphire sample was also character-ized under the same conditions. After the first laser pulse, there is no clear indication of a transformation besides some broad Raman bands which may be due to partial phase transformation to α-alumina. Following the repeated laser pulses, clear α-alumina bands are observed in the spectra, which are comparable with findings of Rena et al. [16].

Figure 4: Raman spectra of the deposited layer after various laser pulses and of the sapphire refer-ence.

Figure 5: XPS spectra of the deposited layer (a) before and (b) after a single laser pulse.

31

[12] M. Veith, E. Sow, U. Werner, C. Peters-en, C. Aktas; Eur. J. Inorg. Chem. (2008), 5181.[13] C. Aktas, B. Afrooz, C. Akkan, J. Lee, M. M. Miró, M. Veith; submitt ed to Materials Lett er.[14] H. Li, S. Costi l, V. Barnier, R. Oltra, O. Heintz, C. Coddet; Surf. Coat. Technol. 201 (2006), 1383.[15] A. Y. Vorobyev, C. Guo; Appl. Surf. Sci. 253 (2007), 7272.[16] R. Krishnan, R. Kesavamoorthy, S. Dash, A. K. Tyagi, B. Raj; Scripta Materialia 48 (2003), 1099.

[6] C. C. Berndt, G. N. Haddadt, A. J. D. Farmer, K. A. Gross; Mater. Forum 14 (1990), 161.[7] T. J. Webster, R. W. Siegel, R. Bizios; Scr. Mater. 44 (2001), 1639.[8] E. M. Christenson, K. S. Anseth, J. J. J. P. van den Beucken, C. K. Chan, B. Ercan, J. A. Jansen, C. T. Laurencin, W.-J. Li, R. Muru-gan, L. S. Nair, S. Ramakrishna, R. S. Tuan, T. J. Webster, A. G. Mikos; J. Orthopaed. Res. 25, 1 (2007), 11.[9] T. J. Webster, L. S. Schalder, R. W. Sie-gel, R. Bizios; Mat. Res. Soc. Symp. Proc. 662 (2001).[10] G.M. Luz, J.F. Mano; Comp. Sci. and Technol. 70 (2010), 1777.[11] M. Veith, S. Faber, R. Hempelmann, S. Janssen, J. Prewo, H. Eckerlebe; J. Mater. Sci. 31 (1996), 2009.

32

fects are discussed to potentially cause inflammatory or immune responses, promote allergies or cardio-vascular diseases or induce cancer. In contrast, inorganic nanomaterials might also en-ter the human body, when used for in-tended applications in the biomedical field, for example tumour therapy or bioimaging [2]. Here, the materials are clearly designed to bring about a ben-efit; nevertheless the materials also have to be proven safe.

The potential effects of nanomaterials on human health, but also on other or-ganisms and the environment are cur-rently a field of active research. Until now, the mechanisms triggering a re-sponse of single cells to the presence of nanomaterials are not completely elucidated. This is due to the vast mul-titude of material types available, dif-fering in material composition, crystal-linity, size, morphology, and surface modification, to name only a few of the relevant characteristics [3]. Identi-fying a general answer to the question: “What makes a nanomaterial poten-tially toxic?” poses a great challenge. This is because some materials act by release of ions; some are regarded to act by their catalytic activity, whereas others are apparently insoluble and chemically inert. All types of nanoo-bjects have in common that they are small enough to enter single cells [4]. In many biomedical applications, such as in drug delivery, gene transfer or labelling, internalisation of nanoob-jects by cells is desired. Therefore, it is assumed that the uptake of nanoo-bjects into living cells and potential in-vasion into subcellular structures also account for their effects, no matter if they are beneficial or detrimental.

In contrast, many living organisms are known to naturally synthesise inorgan-ic materials for a variety of reasons, e.g. to improve mechanical properties. Such materials, well known as bone,

Abstract

The uptake of engineered nanoobjects into cells is assumed to significantly account for their potential toxicity. By internalisation, nanoparticles are at least temporarily trapped in the confined volume of a single cell and come into close contact with cellular components, like organelles, struc-tural proteins, enzymes or signalling molecules. As cells are highly struc-tured entities, exhibiting various types of chemically and biologically distinct compartments, first of all the uptake mechanism determines which types of molecules are encountered. In this review, an introduction into the com-partmentalisation of cells as well as some uptake processes is given. The localisation of engineered materials within cells of human and animal ori-gin is exemplified. On the other hand, many living organisms are known for their ability to intracellularly pre-cipitate inorganic structures. Some of these biogenic materials are chemi-cally and structurally similar to ar-tificially generated nanostructures. Therefore, the localisation of some biogenic structures within cells is also illustrated. Finally, the relevance of the specific cellular localisation for toxicity is discussed.

Introduction

In case of an unintended exposition, engineered inorganic nanoobjects might enter the human body through various routes. The presence of such materials in close vicinity to different types of cells, covering organs like the lung, the gastro-intestinal tract, mu-cous membranes or the skin, might cause effects on a cellular level, for example cytotoxicity, generation of reactive oxygen species, release of signalling factors or cytokines [1]. On the level of the whole body, such ef-

The intracellular localization of inorganic engineered versus biogenic materials: a comparison

Melanie Kucki, Annette Kraegeloh, Nano Cell Interactions Group

33

compartments (fi gure 1) exist: a) the cytosol and the nucleus, topologically being conti nuous, b) the Endoplasmic Reti culum (ER), Golgi apparatus, en-dosomes, lysosomes and transport vesicles, whose interior has to be re-garded as topologically equivalent and derived from the exterior of the cell, c) mitochondria, and d) plasti ds – in plants only –, both of which are sur-rounded by a double membrane, and evolved from internalised bacteria [6].

Intracellular transport, uptake and export of substances

Transport of macromolecules, e.g. pro-teins, between these compartments is mediated by three mechanisms: Gated transport through nuclear pores exchanges molecules between the cytosol and the nucleus. Transmem-brane transport through specialised membrane spanning protein complex-es enables the transport of proteins across membranes, for example from the cytosol into the lumen of the ER. In order to pass through the transport complexes, proteins have to unfold during this process. Transport through membrane proteins also ferries low molecular weight compounds and ions into and out of cells. Vesicular trans-port occurs between compartments that are topologically equivalent, e.g. the ER, Golgi apparatus and all kind of cytoplasmic vesicles. It also mediates import (endocytosis) and export (exo-

teeth or nacre, are oft en made as composites, containing inorganic and organic structures as building blocks assembled by nanoscopic components [5]. Some of these biogenic materials are even produced intracellularly. The questi on arises, why on the one hand the synthesis of inorganic materials by living organisms does not seem to pose any threat, at least to the organ-isms that build them, whereas, engi-neered materials composed of similar elements should aff ect cells.

Intracellular compartmentalisati on

Cells, the universal units of living or-ganisms, are enclosed by the plasma membrane. This thin two-dimensional lipid bilayer separates the cellular con-tent, the cytoplasm, from the extracel-lular space. Proteins embedded in the membrane mediate transport of sub-stances across the membrane, build up ion gradients, structurally link in-ner and outer components and detect or transduce signals from one side of the membrane to the other. Lipid bi-layers are also present inside cells; but whereas prokaryoti c cells (Bacteria, Archaea) generally exhibit a rather low level of inner compartmentalisati on, cells of eukaryoti c organisms (animals, plants, and fungi) contain a multi tude of cytoplasmic membrane-bound com-partments called organelles (Figure 1).

Compartmentalizati on not only serves to increase membrane area, but also provides disti nct reacti on spaces of various compositi ons. From an evo-luti onary point of view, membrane bound organelles presumably originat-ed by invaginati on of small membrane patches surrounding aqueous liquid from the extracellular space, fi nally pinching off as vesicles. Because cells are generally not able to reconstruct single organelles, these are passed on from mother to daughter cells. As a result, four types of intracellular

Figure 1: Compartmentalisati on and organelles of animal cells. Membranes are indicated by red lines. Topologically equivalent – although not necessarily chemically identi cal – spaces (see text) are indicated by colouring [aft er [6]]. Main functi ons of important organelles are given in the legend.

34

cell-type, macropinosomes might be targeted towards the lysosomal sys-tem or back to the cell surface [8].

All mammalian cells carry out clathrin-mediated endocytosis that is respon-sible for processes like internalisa-tion of nutrients, signal transduction, communication, and homeostasis. The process involves binding of the transported cargo to clathrin-coated pits, occupying 2 % of the cell surface, invagination and subsequent forma-tion of clathrin-coated vesicles [6]. The geometry of the formed vesicles is determined by cytosolic self-assembly of clathrin. The binding of the clathrin-coat to the plasma membrane and transmembrane proteins is mediated by specific adaptor proteins, thus ena-bling selective uptake of cargo. The pinch-off of vesicles is mediated by the action of further proteins, for example dynamin. The clathrin coat is shed off from the vesicle surface shortly after vesicle formation. Vesicles might con-secutively fuse with early endosomes, late endosomes and finally lysosomes [7; 6].

Caveolae (“little cavities”) are present on the surface of many cell types, for example endothelial cells [9]. Caveolae are regarded to be a subtype of lipid rafts – membrane patches enriched in cholesterol and sphingolipids – addi-tionally containing caveolin. This pro-tein is anchored to the inner leaflet of the plasma membrane via a hairpin and is involved in the formation of the caveolae structure [10]. Caveolae are involved in signalling processes, but a role in inducible endocytosis has been suggested. Caveolae mediated endo-cytosis seems to require rearrange-ment of the actin cytoskeleton as well as the activity of dynamin in order to pinch off caveosomes [11]. Cave-osomes are distinct from endosomes, formed by clathrin mediated uptake, in content, pH, and fate, for example

cytosis) of substances into and out of the cytoplasm. Endocytosis denotes a group of mechanistically distinct pro-cesses that are tightly regulated [6].

Phagocytosis (“cell eating”) is car-ried out by specialised cells of the human body and mediates internali-sation of large cargo. Macrophages, neutrophils, and dendritic cells use this process to remove senescent or apoptotic cells as well as microorgan-isms. Phagocytosis is induced by acti-vation of specific cell surface receptors and involves the actin cytoskeleton. The phagosome with its cargo subse-quently fuses with lysosomes, the sites of intracellular digestion. Lysosomes contain hydrolytic enzymes that are most active at acidic conditions. A pH value of about 4.5 within lysosomes is established by a vacuolar H+-ATPase present in the lysosomal membrane. Undigestible content might be stored within lysosomes in form of residual bodies or eliminated from the cell by excretion of the lysosomal content. Furthermore, lysosomes receive mate-rials from endosomes (see below) and autophagosomes, responsible for se-lective degradation of cellular content or organelles [7].

Pinocytosis (”cell drinking”) takes place in all cells and besides being responsi-ble for the uptake of nutrients and ex-tracellular fluid, it is also involved in regulatory processes like signalling. In general, pinocytosis is an active pro-cess, by which a cell ingests 100% of its plasma membrane every 30 - 90 min [6]. Various types of mechanisms are known, involving different sets of proteins and accessing distinct targets. Macropinocytosis is a transiently in-duced process, mediated by an actin-driven formation of membrane protru-sions. After their collapse on the plas-ma membrane, macropinosomes are generated that contain large amounts of extracellular fluid. Depending on the

35

are only poorly defi ned. Approaches relying on pharmacological inhibiti on might not be able to reliably elucidate uptake pathways because of lacking specifi city [15]. Last but not least, the dynamics in vesicle life cycles, e.g. in-vaginati on, pinching off , shedding off the vesicle-coat, and docking are very fast processes. Thus, it is not easy to detect a correlati on between exam-ined components, especially using non-living cells for analysis.

In general, nanomaterials are regarded to be taken up by processes resulti ng in enclosing of the materials within membrane bound vesicles [3; fi gure 2]. Uptake by phagocytosis is dependent on the size and surface modifi cati on of the nanoparti cle type and can be en-hanced by opsonisati on, for example

viruses that are internalised by ca-veosomes like SV40 do not enter lys-osomes, but move to the ER [12].

In order to compensate for the conti nu-ous process of membrane removal, and to enable recycling of membrane pro-teins as well as to allow for secreti on of substances synthesised inside of cells, endocytosis is conti nuously linked to exocytosis. The latt er process can be described as vesicle mediated transport directed to the plasma membrane [6].

Uptake, transport and localisati on of engineered nanoparti cles in cells:facts and hypothesis

Although investi gati ons on the inter-nalisati on of inorganic nanoobjects have already been conducted, it is very diffi cult to identi fy general mecha-nisms. First of all, a vast variety of ma-terials have been used for such inves-ti gati ons. Amongst other approaches, the localisati on and toxicity of fl uores-cently labelled polystyrene beads has been studied [13; 14]. Oft en material characteristi cs have not been defi ned properly, parti cularly in presence of cell culture media, which oft en causes agglomerati on of nanoobjects and for-mati on of larger enti ti es. Agglomera-ti on is important, because size is one of the main factors determining poten-ti al internalisati on by cells. The larger the structures are the more unlikely is a penetrati on through the membrane or uptake by non-phagocyti c mecha-nisms. Because of the small size of both, nanoobjects and cellular structures, an exact localisati on is a sophisti cated task, necessitati ng the applicati on of advanced imaging techniques. Addi-ti onally, not every cell type expresses the machinery for every known uptake pathway or transfer-mechanism, even under conventi onal culture conditi ons. Some uptake mechanisms like clathrin and caveolin independent mechanisms

Figure 2: Localisati on of SiO2 nanoparti cles (red) in membrane bound vesicles within living A549 alveolar epithelial cells; cellular membranes and vesicles are stained green by use of GFP. Confocal image, C. Schumann, S. Schübbe; labelled parti cles C. Cavelius.

36

nanoparticles with unknown surface entered endothelial cells as well as red blood cells (note: red blood cells lack endocytotic uptake mechanisms). The cytoplasmic particles were not mem-brane bound, also indicating a non endocytotic uptake process into en-dothelial cells.

After uptake into membrane bound vesicles, nanoparticles seem to be trapped within this compartment [24; 25]. Nanoparticles might further exit the cell by exocytosis. Such a process has been described by Jiang et al. [19] for quantum dots after transport into the lysosomal compartment. The acid-ic environment within this organelle might also dissolve nanomaterials [26], in addition to the action of oxidising species. Less susceptible materials will withstand the digestive process or might exit into the cytosol. The latter can be achieved by a process called en-dosomal escape [3; 27], hypothesised to mediate the release of organic na-nomaterials into the cytosol. Briefly, unsaturated amino groups sequester protons pumped into the lysosome by action of the vacuolar-ATPase, thereby causing enrichment of Cl--ions, osmot-ic swelling and rupture of the lysoso-mal membrane. The release of nano-particles into the cytosol is a prerequi-site for the transport into the nucleus that for example has been described for SiO2 nanoparticles [28; 29], but also for gold nanoparticles [30]. A quantita-tive TEM-analysis of the distribution of 15 nm gold nanoparticles coated with polyethylenglycol or stabilised with citrate showed that both particle types were present in various types of vesicles. No particles were detected in the nucleus, mitochondria, ER or the Golgi apparatus. Only a minority of PEG-coated particles were observed in the cytosol [31]. In comparison, silver nanoparticles (6-20 nm in size, starch-coated) were found to enter mitochon-dria of human glioblastoma cells [32].

by binding of serum constituents to the particle surface [16; 17]. Addition-ally, the agglomeration of nanopar-ticles might trigger uptake by phago-cytic cells [18].

Clathrin mediated endocytosis has for example been shown to mediate the uptake of penicillamine coated quan-tum dots into human cervix carcinoma cells. In addition, uptake seemed to be catalysed by macropinocytosis, al-though to a much lesser extent. The particles were subsequently transport-ed to lysosomes [19]. Uptake of car-boxylated quantum dots into human epidermal keratinocytes seemed to be mediated via binding to lipid rafts, but colocalisation analysis did not indicate involvement of caveolin or clathrin in the uptake process. Subsequently, quantum dots were transported to lys-osomes [20].

A few examples indicate that nanopar-ticles might also directly penetrate the lipid bilayer. By scanning probe micros-copy studies on supported bilayers, Leroueil et al. [21] discovered that not only cationic molecules and dendrim-ers, but also cationic inorganic nano-particles up to a size of 50 nm induce membrane disruption. This seems to be supported by the finding that such particles enter cells by a passive pro-cess (at 4°C) and enhance leakage of cellular substances into the surround-ing [22]. Using 5 nm gold nanoparticles coated with a striped shell of unpolar and negatively charged groups, Verma et al. [23] found that these particles entered the cells rapidly by membrane penetration in addition to endocytosis. In contrast to cationic nanoparticles, the striped ones did not generate holes and cytotoxicity, possibly because of non-disruptive fusion of the nanopar-ticle surface with the membranes. A study by Geiser et al. [15] showed that negatively charged TiO2 in vivo (prima-ry particle size 4 nm) and 25 nm gold

37

an alkaline environment [5]. The mag-netosomes are aligned to form chains inside of the cells by att achment to a cytoskeletal fi lament which is similar to eukaryoti c acti n [37].

Marine algae, the so called cocco-lithophores or calcareous algae, are covered by a shield of various types of calcite crystals, arranged as rings. The calcite structure is formed intra-cellularly within specialised coccolith vesicles that have already been iso-lated from the model organism Pleu-rochrysis carterae. Similar to magne-tosomes, coccolith vesicles contain a number of proteins that control the mineralisati on process. Very promi-nent is the presence of a vacuolar ATPase that serves to pump protons into the vesicles, pointi ng to a deriva-ti on of the coccolith vesicles from the Golgi network. Inside of the Golgi ap-paratus, Ca2+-ions together with acidic polysaccharides form 25 nm parti cles, called coccolithosomes. These are transported within small vesicles to the coccolith vesicles, the places of cal-cite mineralisati on [38]. Mature cocco-liths leave the cells by exocytosis [39]. Foraminifera, unicellular organisms which are one of the major CaCO3 pro-ducers in the oceans, have been found to take up seawater via fl uid phase en-docytosis [40].

Diatoms are unicellular algae that pos-sess a highly structured cell wall made of a composite material consisti ng of amor-phous polysilicic acid and ti ghtly bound organic molecules like proteins or poly-amines. This pillbox shaped casing pro-tects the cell from mechanical damage and predati on (fi gure 3). Investi gati ons on the ultrastructure of the diatom cell wall revealed the presence of building blocks in form of partly fused silica nano-parti cles [41]. In diatoms, the formati on of the silica shell (frustule) takes place in special membrane bound vesicles, the so called silica depositi on vesicles (SDVs). In diff erence to the calcareous al-

Intracellular generati on of inorganic structures by living organisms

Biomineralisati on of inorganic matt er is widespread throughout the living world. Examples are silica in diatoms, radiolarian, plants, iron oxide in bac-teria and multi cellular organisms (fi sh, human brain), calcium carbonate in calcareous algae, shells of birds and molluscs, as well as calciumphosphate and apati te in bone and teeth [5]. Also more exoti c biominerals equivalent to atacamite (Cu2(OH)3Cl) in the jaws of bloodworms [33] or celesti te (SrSO4) present in the skeleton of Acantharia exist. In many cases, nanostructured mineralisati on intermediates or prod-ucts are formed inside of single cells, without causing known adverse ef-fects. Some examples shall illustrate what is known about the cellular lo-calisati on of these biomineralisati on processes.

Many bacteria are able to precipitate inorganic materials either extra- or intracellularly. Examples are the for-mati on of silver nanoparti cles by the silver resistant strain Pseudomonas stutzeri AG259 [34] mainly within the periplasm or the formati on of iron oxide by the anaerobic iron reducing bacterium Shewanella putrefaciens within the cytosol [35]. In contrast, magnetotacti c bacteria, for example Magnetospirillum gryphiswaldense, form crystals of magneti te in the size range of 40 - 120 nm in special orga-nelle-like structures called magneto-somes. The magnetosome membrane is hypothesised to originate from in-vaginati on of the plasma membrane [36]. Magnetosomes harbour the pro-teins that control the parti cle forma-ti on and stabilise the crystals against agglomerati on. Prior to the mineralisa-ti on process, iron ions in form of Fe(II) or Fe(III) need to be transported into the magnetosomes, during the pro-cess, protons are exported to ensure

38

SDV structure, its molecular composi-tion as well as its origin are consistent. Even if diatoms and sponges are among the best studied organisms in this field, there is still a large gap of knowledge regarding the detailed structural fea-tures and underlying processes. In plants, the formation of phytoliths also poses a poorly studied field [52].

Conclusion

Engineered nanoobjects might enter cells via various internalisation routes that primarily determine which cellular components are directly encountered. Until now, most nanoobjects seem to enter cells by endocytosis. Hence, these nanomaterials are – at least ini-tially – separated from the cytosol by the surrounding vesicle membrane. The degradation of soluble engineered materials, for example under the acid-ic and oxidising conditions within lys-osomes, might cause release of materi-al components or ions into the cytosol. A toxic effect will occur, as soon as the buffer capacity of the cytoplasm for the respective element is exceeded. In comparison, known examples of or-ganisms that synthesise inorganic ma-terials within the cytoplasm indicate that these materials are similarly en-closed by intracellular membranes. In addition, similar mechanisms seem to mediate internalisation and processing of inorganic materials. The separation serves to protect the cells from unde-sirable effects of soluble components or precursors of the synthesised ma-terials. In addition, the compartments act as reaction vessels, providing suit-able conditions for the mineralisation process. Therefore, knowledge derived from investigations on the molecular mechanisms involved in biogenic min-eralisation processes within cells can help to understand cell-nanoparticle interactions of engineered materials.

gae, the formation of the new silica wall takes place shortly before cell division. In the cytoplasm of newly formed daugh-ter cells, two new hypovalves are gen-erated synchronously within enlarging SDVs [38]. During new valve formation, relevant amounts of silicic acid have to be transported to the SDVs. One hy-pothesis states that silicon transporters are involved in this process. However, in this case a premature condensation of the silicon precursors within the cytosol has to be circumvented [42]. Another hy-pothesis suggests that transport of or-thosilicic acid takes place through small silicon transport vesicles [43]. Recent investigations indicate that macropino-cytosis is primarily involved in silicon up-take [44] and corroborate the assump-tion that this process is involved in the so-called “surge-uptake” of silicon at the beginning of valve formation [42]. In contrast to an earlier hypothesis, assum-ing that SDVs are derived from the Golgi apparatus [38], the former assumes that the macropinosome transforms into the initial SDV [42]. The uptake of silicon via endocytosis has also been described for some types of higher plants, thus circumventing incompatible concentra-tions of precursors or metal ions in the cytosol [45]. As plants and diatoms were shown to incorporate aluminium into their silica structures, preventing high accumulation of this element within the cytoplasm [46; 47], the formation of bio-genic structures might additionally serve detoxification.

An annular structure made of silica nanoparticles was also found in cross-sections of spicules of the demos-ponge Tethya aurantia [48] and the hexactinellid sponge Euplectella as-pergillum [49; 50]. SDVs seem to be involved in the mineralisation of silica in sponges as well as in flagellated pro-tists (Choanoflagellates, Dinoflagel-lates, Silicoflagellates) [51]. However, it is largely unknown to what extent the

Figure 3: Marine diatom Coscinodiscus wailesii (cell diameter 200 µm), cell wall in vivo-la-beled with rhodamine B (yellow); chloroplasts with intrinsic chlorophyll fluorescence (red); fluorescence microscopical image, M. Kucki; T. Fuhrmann-Lieker, Universität Kassel.

39

[8] Kerr M. C., Teasdale R. D.; 2009; Traffi c; 10: 364-371[9] Rothberg K. G.; 1992; Cell; 68: 673-682 [10] Fernandez I.; 2002; Proc Natl Acad Sci USA; 99 (17): 11193-11198 [11] Fielding C. J.; editor; 2006; Lipid Raft s and Caveolae; Wiley-VCH, Weinheim[12] Pelkmans L., Helenius A.; 2002; Traffi c; 3: 311-320[13] Xia T., Kovochich M., Liong M., Zink J. I., Nel A. E.; 2008; ACS Nano; 2 (1): 85-96[14] Geiser M., Rothen-Ruti shauser B., Kapp N., Schürch S., Kreyling W., Schulz H., Semmler M., Im Hof V., Heyder J., Gehr P.; 2005; Environ Health Persp; 113 (11): 1555-1560[15] Ivanov A. I.; 2008; in: Exocytosis and Endocytosis; Ivanov A. I., editor; Humana Press, Totowa, US; 15-33[16] Monopoli M. P., Walczyk D., Campbell A., Elia G., Lynch I., Bombelli F. B., Dawson K. A.; 2011; J Am Chem Soc; 133: 2525-2534 [17] Dobrovolskaia M. A., McNeil S. E.; 2007; Nat Nanotechnol; 2: 469-478[18] Kuhlbusch T. A. J., Krug H. F., Nau K.; editors; 2009; NanoCare Final Scienti fi c Report; Dechema e. V.[19] Jiang X., Röcker C., Hafner M., Brand-holt S., Dörlich R. M., Nienhaus G. U.; 2010; ACS Nano; 4 (11): 6787-6797[20] Zhang L. W., Monteiro-Riviere N. A.; 2009; Toxicol Sci; 110 (1): 138-155[21] Leroueil P. R., Berry S. A., Duthie K., Han G., Rotello V. M., McNerny D. Q., Baker J. R., Orr B. G., Holl M. M. B.; 2008; Nano Lett ; 8 (2): 420-424[22] Leroueil P. R., Hong S. Y., Mecke A., Baker J. R., Orr B. G., Holl M. M. B.; 2007; Acc Chem Res; 40 (5): 335-342 [23] Verma A., Uzun O., Hu Y., Hu Y., Han H. S., Watson N., Chen S., Irvine D. J., Stellacci F.; 2008; Nat Mater; 7: 588-595[24] Chithrani B. D., Ghazani A. A., Chan W. C. W.; 2006; Nano Lett ; 6 (4): 662-668[25] Derfus A. M., Chan W. C. W., Bhati a S. N.; 2004; Adv Mater; 16 (12): 961-966[26] Xia T., Kovochich M., Liong M., Mädler L., Gilbert B., Shi H., Yeh J. I., Zink J. I., Nel A. E.; 2008; ACS Nano; 2 (10): 2121-2134[27] Panyam J., Zhou W. Z., Prabha S., Sa-hoo S. K., Labhasetwar V.; 2002; FASEB J; 16: 1217-1226[28] Chen M., von Mikecz A.; 2005; Exp Cell Res; 305: 51-62[29] Schübbe S., Schumann C., Cavelius C., Koch M., Kraegeloh A.; in preparati on[30] Rothen-Ruti shauser B., Mühlfeld C., Blank, F., Musso C., Gehr P.; 2007; Part Fib-re Toxicol; 4: 9

The questi on arises, whether engi-neered nanoobjects are more toxic when they leave the enclosing mem-brane envelope and enter the cytosol, the nucleus or other organelles. A di-rect interacti on of nanoobjects and cytosolic components is only possible aft er escape from the vesicles involved in endocytoti c pathways. Aft er poten-ti al entry into the cytosol, cytosolic proteins might cover the parti cle sur-face and mediate transfer of the par-ti cles into further organelles. The pro-tein cover might also serve to prevent the secondary release of ions from the parti cle surface. Overall, the mol-ecules covering the surface of nanoo-bjects might not only assist in inter-nalisati on of nanoobjects into cells by mediati ng binding to cellular surfaces. They might also direct nanoobjects to secondary target organelles. Future in-vesti gati ons in the fi eld of nanotoxicol-ogy will have to consider a correlati on between internalisati on effi ciency and toxicity. In additi on, it is relevant to dis-cover how nanoparti cles gain access to the cytosol, how they are transported into secondary organelles and which parameters infl uence the effi ciency of both processes.

References

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E. G., Wolterbeek H. T.; 2010; Silicon; doi:10.1007/s12633-010-9059-2 [43] Schmid A. M., Schulz D.; 1979; Proto-plasma; 100: 267-288[44] Hildebrand M., Kim S., Shi D., Scott K., Subramaniam S.; 2009; J Struct Biol; 166: 316-328[45] Neumann D., De Figueiredo C.; 2002; Protoplasma; 220: 59-67[46] Epstein E.; 1999; Annu Rev Plant Phy-siol; 50: 641-664[47] Britez R. M., Watanabe T., Jansen S., Reissmann C. B., Osaki M.; 2002; New Phy-tol; 156: 437-444[48] Weaver J. C., Pietrasanta L. I., Hedin N., Chmelka B. F., Hansma P. K., Morse D. E.; 2003; J Struct Biol 144: 271-281[49] Aizenberg J., Sundar V. C., Yablon A. D., Weaver J. C., Chen G.; 2004; Proc Natl Acad Sci USA; 101 (10): 3358-3363[50] Aizenberg J., Weaver J. C., Thanawala M. S., Sundar V. C., Morse D. E., Fratzl P.; 2005; Science; 309: 275-278[51] Preisig H. R.; 1994; Protoplasma; 181: 29-42[52] Currie H. A., Perry C. C.; 2007; Ann Bot-London; 100: 1383-1389

[31] Brandenberger C., Mühlfeld C., Ali Z., Lenz A. G., Schmid O., Parak W. J., Gehr P., Rothen-Rutishauser B.; 2010; Small; 6 (15): 1669-1678[32] AshaRani P. V., Mun G. L. K., Hande M. P., Valiyaveettil S.; 2009; ACS Nano; 3 (2): 279-290[33] Lichtenegger H. C., Schöberl T., Bartl M. H., Waite H., Stucky G. D.; 2002; Sci-ence; 298: 389-392[34] Klaus T., Joerger R., Olsson E., Granq-vist C. G.; 1999; Proc Natl Acad Sci USA; 96 (24): 13611-13614[35] Glasauer S., Langley S., Beveridge T. J.; 2002; Science; 295: 117-119[36] Jogler C., Schüler D.; 2009; Annu Rev Microbiol; 63: 501-521[37] Erickson H. P.; 2001; Nature 413: 30[38] Marsh M. E., Dickinson D. P.; 1997; Protoplasma; 199: 9-17[39] Bentov S., Brownlee C., Erez J.; 2009; Proc Natl Acad Sci USA; 106 (51): 21500-21504[40] Hildebrand M., Doktycz M. J., Allison D. P.; 2008; Pflug Arch Eur J Phys; 456: 127-137[41] Bäuerlein E.; 2003; Angew Chem Int Edit; 42 (6): 614-641[42] Brasser H. J., van der Strate H. J., Gieskes W. W. C., Krijger G. C., Vrieling

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ing ti lted or slanted fi brillar structures. Diff erent approaches varying from heated rollers to photolithography and etching processes at well-defi ned angles were presented by diff erent speakers to eff ecti vely produce an-isotropic shear behavior. Mechanical engineer Meti n Sitti (Carnegie Mellon University, Pitt sburgh, USA) showed advanced ti lted structures, but argued that, for many technological applica-ti ons, isotropic adhesion behavior is required and directi onality could lead to easy failure.

Reversibility

Biologist Kellar Autumn (Lewis & Clark College, Oregon, USA) gave an over-view of the current understanding of gecko adhesion. He explained that one of the key features is the non-sti cky default state of att achment pads that requires a proximal shear load to be switched to an adhesive state (“fric-ti onal adhesion”). To detach, the gecko releases the grip and peels the toes outward, returning the pads to the non-sti cky state. Mechanical engineer Huajian Gao (Brown University, Provi-dence, USA) presented a fundamental contributi on to the current under-standing by proposing a pre-stress model. Proximal shear generates a pre-stress in the spatulae that “turns on” adhesion. Moreover, above a criti -cal angle the pre-stress dramati cally decreases the peel-off force to nearly zero, thus enabling the gecko to detach eff ortlessly and independently of the applied force. The great challenge to mimic this specifi c mechanism of “on demand” strong adhesion and easy release is being explored by several research groups using topographical changes upon applying an external sti mulus:

1) Mechanical engineer Kimberly Turn-er (University of California at Santa Barbara, USA) presented microfab-

In July 2010, scienti sts from all over the world gathered at INM to discuss gecko inspired adhesion at a workshop enti tled „Bioinspired adhesion: from geckos to new products“. The talks covered a range of current issues, in-cluding natural att achment systems, developments in arti fi cial gecko-mim-ics, advances in mechanical models and possible products. This was the fi rst dedicated workshop on this topic. The att endees unanimously agreed to create an internati onal workshop se-ries based on the INM example.

Researchers have pondered the prin-ciples of gecko-adhesion for nearly a century. Unlike many conventi onal adhesives that can only be used once on clean surfaces, foul and att ach ac-cidentally to inappropriate surfaces, natural so-called “dry adhesives” are reversible, durable, controllable and self-cleaning. The key strategy in dry adhesives is the formati on of struc-tures, i.e. fi brillar surfaces or complex subsurface patt erns. Over the past decade, many research groups around the world became interested in dry adhesion and made great advances in understanding the principles and de-veloping arti fi cial mimics. At the work-shop, this community of biologists, material scienti sts, physicists and engi-neers was brought together to discuss the status and future challenges.

Directi onality

In the opening address, biologist Wal-ter Federle (Cambridge University, UK) stressed the diversity in natural at-tachment systems using a variety of examples including ants, cockroaches and beetles. He documented the direc-ti onality in adhesion and showed how individual parts of adhesive setea have diff erent functi ons (pulling vs. pushing) facilitati ng up and downward climbing. Several material scienti sts att empt to mimic directi onal adhesion by fabricat-

“Gecko-Workshop 2010” – INM initi atesnew worldwide conference series

Marleen Kamperman, Eduard Arzt, Functi onal Surfaces Group

42

(University of California at Berkeley, USA), Kaph-Yang Suh and Metin Sitti. Physicist Bo Persson (IFF Research In-stitute, Jülich, Germany) stressed the importance of roughness in a variety of applications and presented his con-tact mechanics theory for friction on rough surfaces. In a different context it was shown by mechanical engineer Paolo Decuzzi (University of Texas, Aus-tin, USA) that the effect of roughness on cell adhesion can be modeled by balancing contributions from specific and nonspecific binding and strain en-ergies.

Design rules

Most participants agreed that the ul-timate aim is not to fabricate exact copies of natural examples but rather to extract underlying design principles. Alfred Crosby (University of Massachu-setts, Amherst, USA) emphasized this by proposing scaling laws that guide dry adhesive design based on system geometry and material stiffness. He showed how complex hierarchical sys-tems can be modeled by addition of separate elements using their compli-ances. Many researchers presented advanced artificial structured adhe-sives, but used different design criteria. Yohei Maeno (Nikko Denko Corp., Ja-pan) and Ronald Fearing both stressed the importance of using materials with high bulk stiffness (polypropylene and carbon nanotubes, respectively) and low effective elastic modulus due to its specific surface structure. Animangsu Ghatak (IIT Kanpur, India) and Anand Jagota showed intelligent subsurface structure designs that enhance adhe-sion by interfacial crack trapping in dry and wet conditions. Huajian Gao emphasized that adding levels of hier-archy can enhance adhesion strength up to the point that the material itself becomes the weakest link. Kaph-Yang Suh also mentioned material limita-

ricated actuated adhesives based on magnetic, thermal and piezoelectric switching using cantilever and latches.

2) Materials scientist Eduard Arzt of INM presented shape memory poly-mer and elastomer based microfibril-lar arrays that were shown to actu-ate upon temperature and pressure changes, respectively.

3) Materials scientist Kaph-Yang Suh (Seoul National University, S-Korea) showed adhesion actuation using stretching of fibrillar arrays on a wrin-kled backing layer.

4) Materials scientist Anand Jagota (Lehigh University, Bethelem, USA) showed that self-adherence of subsur-face structures can switch the system from being in compression to tension which alters the adhesion dramatically.

Roughness

Although geckos can adhere to almost any kind of surface most research groups still struggle to make surface structures that adhere strongly to rough surfaces. In conventional pres-sure sensitive adhesives the visco- elastic properties enable large contact areas even for very rough surfaces. Roughness may even enhance adhe-sion to viscoelastic material systems by dissipation of energy through crack arrest which was shown by physicist Anke Linder (ESPCI, Paris, France). Fol-lowing similar reasoning, physicist Christophe Poulard (Paris University, France) presented how surface pat-terning can enhance the peel strength of pressure sensitive adhesives and elastomers. Many scientists agree that for patterned dry-adhesives with mini-mal viscoelastic properties to adhere strongly to rough substrates, hierarchi-cal designs will be required. Promis-ing developments were presented by mechanical engineer Ronald Fearing

43

Aft er three days of high quality lec-tures one questi on remained: Has ti me come for a technological break-through of gecko-adhesives? We might be close, as evidenced by encouraging results in large scale patt erning and proof-of-principle applicati ons shown by Mike North (North Design Labs) and Peter de Oliveira (INM) and also indi-cated by the large number of parti ci-pants from industry.

ti ons and emphasized that more ef-forts are required to develop materials systems that accommodate require-ments other than adhesion. One of the highlights of the workshop was a recent theory presented by Huajian Gao on how humidity may aff ect the adhesion in geckos. He proposed that humidity in air changes the sti ff ness of gecko setae which in turn alters adhe-sion.

Test methodology

Convergence of testi ng methodology was one of the goals set for the work-shop. Many agreed that it is hard to compare diff erent designs because of the wide variety of tests used to evaluate the adhesion performance. In additi on, new methodology specifi -cally designed for dry adhesion may be required. Eduard Arzt presented the development of a canti lever based ad-hesion tester at INM and showed that only slight misalignments between mi-cropatt erned sample and fl at probe re-sult in major changes in the measured adhesion. Misalignment issues can be prevented using spherical probes and Anand Jagota reviewed their elegant model-independent method to extract adhesion energy from indentati ons with spherical probes.

44

45

Gruppenberichte /Group Reports

46

47

Darüber hinaus werden durch entspre-chende Wissenschaft ler auch Basisun-tersuchungen vorangetrieben:

• grundlegendes Verständnis des Phänomens der Kratzfesti gkeit von Oberfl ächen,

• Beeinfl ussbarkeit des Benetzungs-verhaltens innerer Oberfl ächen po-röser Körper.

Die Entwicklungen des Programm-bereiches werden auch weltweit im Rahmen von Messen, Tagungen und Roadshows vorgestellt. Zukünft ig wer-den die Akti vitäten erweitert auf das Feld Materialien für die Energietechnik sowie für die Mobilität. Im ersteren Fall wird der Einsatzbereich der opti -schen Nanoparti kel mit photopolyme-risati onskatalyti schen Eigenschaft en auf Solarenergieanwendungen erwei-tert werden. Im zweiten Fall bieten tribologische Beschichtungsmateriali-en signifi kantes Potenti al zur Verbes-serung der Langlebigkeit und Effi zienz von bewegten Systemen.

Der Programmbereich Nanomere ent-wickelt Kompositmaterialien, insbe-sondere Nanokomposite bestehend aus einer polymerarti gen Matrix und anorganischen Nanoparti keln als funk-ti onellen Additi ven. Die Grundidee liegt in der Verknüpfung von festkörperphy-sikalischen Eigenschaft en mit Polymer-verabeitungstechnik, beispielsweise La-ckierverfahren oder Kompoundierungs-methoden. Diese Kombinati on macht die Materialien att rakti v für prakti sche und industrielle Anwendungen. Über die reine Erzeugung von additi ven Ef-fekten interessieren uns morphologi-sche Parameter wie interparti kuläre Abstände und spezielle Grenzfl ächen-eff ekte, die in nanostrukturierten Sys-temen eine durchaus signifi kante Rolle spielen können. Konzepte zur Kompati -bilisierung und zur Erzeugung von Gra-dientenmaterialien werden ebenfalls eingehend untersucht und im Sinne spezifi scher Anwendungen opti miert. Der Programmbereich ist stark techno-logie-orienti ert und besitzt spezielles Know-how zur Materialsynthese über chemische Methoden, das es erlaubt, Materialien mit maßgeschneiderten Eigenschaft en in relati v kurzer Zeit zu entwickeln. Die Arbeiten sind innerhalb des INM gut vernetzt mit anderen Pro-grammbereichen, wie z.B. der Nanotri-bologie oder auch den Opti schen Mate-rialien. Zahlreiche Kontakte im wissen-schaft lichen und industriellen Bereich bestehen daneben auch im nati onalen und im internati onalen Umfeld.

Schwerpunkte der Materialentwick-lung sind:

• verschleißfeste Gleitbeschichtungen mit extrem niedrigem Gleitreibungs-koeffi zienten,

• multi funkti onelle, fl exible Hartbe-schichtungen mit integrierter Barrie-refunkti on,

• funkti onelle opti sche Nanoparti kel,• kompakte Bulk-Nanokomposite.

Nanomere / Nanomers

Dr.-Ing. Carsten Becker-Willinger

48

linear or rotational movements. The Program Division Nanomers is inves-tigating maintenance free low friction coatings with failsafe running func-tions, which show a high wear resist-ance to achieve a long term effect and can contribute to significantly save en-ergy. The composite approach enables to combine a low coefficient of friction, with wear resistance and corrosion protection ability which is important, if steel parts are coated and no grease is present usually avoiding the con-tact with water and by this avoiding corrosion to occur. The Nanomer low friction coatings show a coefficient of friction in the range of µ = 0.1, a wear coefficient of about 2.5 x 10-6 mm³/Nm and a corrosion resistance on mild steel in the neutral salt spray test up to 1000 hrs without blistering and de-lamination. For 2011 an appropriate patent application is planned in this context.

Multifunctional hard coatings

The abrasion resistance of coatings is an indispensable property that is required in most applications. One additional function that can be useful in applica-tions in the oil and gas industry is the protection of low alloyed steel against sweet and sour corrosion. In two pro-jects with industry abrasion resistant corrosion protection coatings have been developed. One application is an internal coating for steel pipes used for produc-tion of oil. Here abrasion resistance is required because the produced oil also contains sand. Besides this the coating protects the pipes against corrosive at-tack by hydrogen sulfide and carbon dioxide which allows using mild steel in-stead of expensive high chromium steel. Another application is the internal pro-tection of steel cylinders for the trans-portation and storage of compressed natural gas also containing hydrogen sulfide as impurity which can lead to

Introduction

The Program Division Nanomers devel-ops new materials based on the com-posite approach, in particular nanocom-posites having a polymer type or hybrid matrix in combination with nanopartic-ulate functional additives. The idea is to combine the intrinsic solid state physical properties of inorganic materials with typical polymer processing technolo-gies such as painting or compounding in order to make the materials attractive for practical applications and industrial use. Morphological parameters that influence the properties of the (nano)composite materials in addition to the pure mixing rule, such as the mean in-terparticulate distance, and special in-terfacial effects that become dominant in the nanoscale range are investigated on the fundamental level in coatings and bulk materials as well. Furthermore, concepts for nanoparticle compatibiliza-tion and gradient formation are studied, developed and are consequently opti-mized towards sustainable material so-lutions for end users. The Program Divi-sion is a technology driven division with a strong concentration of know-how in chemical synthesis which is an impor-tant tool to develop advanced materials. Its activities are cross-linked internally with other INM Program Divisions such as Nanotribology and Optical Materials as well as the process engineering spe-cialists. In addition external collabora-tions with several international research groups on e.g. sol-gel chemistry and with various industrial partners exist worldwide.

Wear and corrosion resistant low friction coatings

Durable and ecologically friendly sur-face finishes that avoid grease for lu-brication, while exhibiting a low coef-ficient of friction, are of high interest for applications in mobile systems with

Figure 1: Pendulum with Nanomer low friction coated and uncoated steel axis.

Figure 2: Porosimeter and permeameter for investigation of rock samples.

49

Polymer matrix nanocomposites

Strain gauges with high sensiti vity are usually fabricated on temperature sta-ble polymer fi lms. During producti on of the multi -layered structures composed of polymer fi lms and inorganic layers, defects and cracks develop because of diff erenti al thermal expansion. To mini-mize this problem, composites with in-organic nanoparti cles that reduce the coeffi cient of thermal expansion of the polymer fi lm are developed. A joint pro-ject on this topic has been performed in co-operati on with the University of Applied Sciences (HTW) in Saarbrücken and the Fraunhofer Insti tute for Bio-medical Research (IBMT). The results re-vealed that the nanocomposite forma-ti on approach applied on the specifi cally chosen polymer leaves the coeffi cient of thermal expansion in the range of the unfi lled polymer of about 20 ppm/K. The behavior was found to be independ-ent on the fi ller content. The results in-dicated that the presence of the inor-ganic nanoparti cles had an infl uence on the cross linking density of the polymer matrix leading to a compensati ng eff ect. The project has been fi nancially sup-ported by the Ministry for Economy and Science of the state of Saarland.

In the area of transparent polymer matrix nanocomposites, nanoparti cles have been used in such matrices to tai-lor opti cal properti es of compact bulk materials and layers. In 2010 readily dispersible high refracti ve index BaTiO3 nanoparti cles free of photo-catalyti c acti vity have been developed and have been incorporated in an acrylic coati ng matrix. The yellowness index could be kept below 1 and the transparency of the materials was almost unchanged. Furthermore one important develop-ment work is dealing with the creati on of special morphologies in polymer based bulk materials which allow the creati on of smart composites with adap-ti ve mechanical and thermo-mechanical

stress corrosion cracking especially in high strength steel. For this reason today conventi onal cylinders must be fabricat-ed from low strength steel and therefore become very heavy. They have a very long lifeti me which means they will be used in more than 10.000 compression / decompression cycles between 20 and 200 bars and are subjected to high tem-perature diff erences during use. The in-ner protecti ve coati ng should withstand all the loadings that can occur during the whole lifeti me of the cylinders which can be in the range of about forty years. The advantage of the successfully developed protecti ve coati ng is now that low weight gas cylinders can be fabricated using steel with higher strength. This helps to save a lot of energy during transporta-ti on while the safety issue is sti ll fulfi lled. For the year 2011 our partners intend to fully integrate the successful result of the material development into the existi ng producti on line. The technology devel-opment requires the chemical up-scal-ing of the synthesis and the fi ne tuning of the applicati on technology for steel pipes with real dimensions. Part of the work will be performed by the Program Division NMO in cooperati on with Nano-mers as the project leader. The materials concept will be protected by patent ap-plicati ons in 2011.

The projects menti oned are part of a strategic co-operati on with a strong technology partner from the oil and gas industry. To extend the acti viti es and to strengthen the competence the Program Division Nanomers has built up a special oil-lab. Its objecti ve is to perform investi gati ons into specifi c oil and gas related topics such as e.g. enhanced oil recovery and the like. Ac-ti viti es in this directi on have been sup-ported by the BMBF (FKz.: 03FPD00027 and FKz.: 03FPD00041). Figure 2 shows some of the available equipment re-lated to the special lab. The results of these two projects actually are subject to patent applicati on process.

Figure 3: TEM micrograph of nanoscaled BaTiO3 directly aft er synthesis.

50

In addition to this, several postdocs are working on new topics: basic mecha-nisms of scratch formation are stud-ied in cooperation with the Program Division Nanotribology; new materials with adjustable mechanical and ther-mal properties for gecko surfaces are investigated in collaboration with the Program Division Functional Surfaces. The tests are performed on bulk sam-ples that allow the investigation of the mechanical surface properties and at the same time the dynamic mechanical-thermal behavior of the bulk materials.

Outlook

Functionalized nanoparticles in com-bination with polymer type matrices promise widespread application in the future. In the field of energy ma-terials, the activities will be extended from oil and gas applications concern-ing corrosion protection and enhanced recovery to renewable energies by use of semiconductor nanoparticles based on the photo polymerization initiator nanoparticles developed in the BMBF project Nanocure. This will open new possibilities in areas such as solar energy and photovoltaics. In the area of mobility especially optimized tribological coating materials will play a significant role. Future activities will also include transparent conductive materials and high gas diffusion bar-rier properties for foils. These topics will be worked out in collaboration together with the Program Divisions Optical Materials, Biomineralization, Nanoprotect, Nanotribology and Struc-ture Formation at Small Scales. From the results of these activities the divi-sion will initiate further activities for a broad range of industrial applications.

properties. A patent application is envis-aged for 2011.

Functionalized nanoparticles

Building blocks in the above mentioned polymer matrix nanocomposites are discrete nanoparticles. In the BMBF pro-ject Nanocure (FKz.: 13N9119) the Pro-gram Division Nanomers has successful-ly developed inorganic nanoparticulate photoinitiators for UV-polymerization reactions that can act as substitutes for common organic molecular photoinitia-tors. The newly developed photoinitia-tor nanoparticles are of special interest for the printing and packaging industry because they cannot migrate and for this reason are suitable to be used in products in contact with food. In 2010 the final up-scaling step up to 10 l per batch has been performed. In addition a joint patent application has been ap-plied together with the University of Saarland.

Antimicrobial and hygienic coatings are of interest in a large variety of applica-tions, especially in the hospital environ-ment where multi-resistant germs and bacteria (MRSA) are present as well as in public areas with high passenger fre-quency. Based on the materials patent base of INM, we are participating in a joint European project dedicated to the development of copper containing hy-gienic coatings (CuVito) which combines copper compounds in the nanoparticu-late range with Vitolane© matrices. The project is performed under a joint call between the EU and Mexico, comprises seven partners from four countries and should lead to commercial applications for copper compounds derived from minerals from Mexican origin. The func-tional elements are copper containing nanoparticulate building blocks to be developed and investigated in the Pro-gram Division Nanomers.

Figure 4: The CuVito approach: Cu nanoparticles as controlled release reservoir for copper ions are attached to a Vitolane© matrix (Vitolane© is a registered trademark of TWI/UK).

51

von 550 °C erlauben. Eine erfolgreiche Entwicklung bilden hier harzarti ge Sol-Gel-basierte Nanobinder mit Feststoff -gehalten bis 70 Gew.%. Diese Material-klasse bildet auch eine aussichtsreiche Materialbasis für die Entwicklung löse-mitt elarmer Bindemitt el, die der EU-VOC-Richtlinie entsprechen.

Im Rahmen einer DFG-Kooperati on mit der Universität Tübingen werden Nanoparti keloberfl ächen mit bioak-ti ven Komponenten modifi ziert. So ist es gelungen, einen Sialinsäure-Precursor zu syntheti sieren, der eine Immobilisierung an Parti keloberfl ä-chen ermöglicht. Durch weitere Modi-fi zierungen sollen diese Verbindungen derart abgewandelt werden, dass sie biologische Funkti onen wie Immun-maskierung, Lebenszeitregulati on oder Zellerkennung nachahmen. Unter Ausnutzung dieser Eigenschaft smerk-male sollen Nanoparti kel und Ober-fl ächen zur Bearbeitung pharmako-dynamischer und medizintechnischer Themenstellungen wie beispielsweise Drug Targeti ng oder Biokompati bilität ausgestatt et werden.

Im Berichtszeitraum wurden die bei-den öff entlich geförderten Projekte

Im Programmbereich Nanoprotect werden zur Entwicklung innovati ver Materialien die drei Basiskomponen-ten Nanoparti kel, Oberfl ächenmodi-fi katoren und Bindemitt el gezielt mit-einander kombiniert. Ergänzt durch kommerziell verfügbare Einzelkom-ponenten lassen sich auf diese Weise Materialkonzepte mit breitem Anwen-dungspotenti al realisieren. Potenti -elle Funkti onalitäten für innovati ve Werkstoff e sind sicherheits- und um-weltrelevante, biokompati ble und res-sourcenschonende Funkti onalitäten wie Isolati on, Korrosionsbeständigkeit, UV-Schutz und Bioakti vität.

In aktuellen Arbeiten konnten grundle-gende Prinzipien ferroelektrischer Par-ti kelpackungen erforscht und Pasten zur Herstellung gedruckter elektroni-scher Komponenten entwickelt wer-den. Anhand der erzielten Ergebnisse soll das Thema Funkti onelle Parti kel-packungen auch für andere Funkti ona-litäten genutzt werden.

In einer weiteren Arbeit werden derzeit schrumpfarme Nanobinder erforscht, die mit geeigneten Zuschlagsstoff en die Herstellung von dichten Bulk-Formkör-pern bei Formtemperaturen unterhalb

Nanoprotect / Nanoprotect

Dr. Bernd Reinhard

PriMeBits (Printable memory soluti ons for sensor, ID and media applicati ons) und UNACON (Use of multi functi onal Nano-Additi ons for innovati ve high performance Concrete Stones) erfolg-reich zum Abschluss gebracht. 2011 werden die Projekte EcoRepair (Ener-gieeffi ziente Reparatur von Glasur-fehlern in Sanitärkeramiken) und das DFG-Projekt „Wechselwirkung modifi -zierter Nanoparti kel mit Erythrozyten zur Toxizitätsabschätzung und Anwen-dung bei Infekti onskrankheiten“ in Ko-operati on mit der Universität Tübingen fortgesetzt.

Im 2. Halbjahr 2010 wurde am INM eine Task Force „Biogene Materialien“ ge-gründet. Die Mitglieder der Task Force bilden ein interdisziplinäres Team aus den Fachbereichen Analyti k, Bioche-mie, Chemie, Physik und Werkstoff -wissenschaft en. Die Zielstellung der Task Force besteht darin, das Potenti al und die Grenzen biogener Materialien, die über Biomineralisati on zugänglich sind, zu ermitt eln und ein Konzept zum Transfer biogener oder bioinspirierter Materialien bei der Materialentwick-lung zu erstellen.

52

ists, chemists, materials scientists and physicists from the Program Divisions Biomineralization, Functional Sur-faces, Optical Materials, Nanoprotect and Structure Formation and from the Service Groups Physical and Chemical Analysis will develop a concept for the transfer of biogenic or bioinspired ma-terials in the engineering of new ma-terials.

Anticorrosive coatings

In 2010, the effect of alumina and me-tallic aluminum on the resistance of steel against high temperature oxida-tion was investigated. A slurry based coating system containing alumina of different size fractions and metal-lic aluminum was tested. The system could suppress the oxidation at 950°C up to 80% compared with uncoated samples.

To avoid particle agglomeration, a suit-able surface modification of SiC was developed. Such corrosion protection coatings showed improved perfor-mance, such as longer lasting protec-tion, higher abrasion resistance and self-healing effect.

Furthermore, the effect of CeO2 in cor-rosion protection was investigated. To obtain a uniform CeO2 coating, a self assembly method was employed us-ing nanodispersed CeO2 slurries and a suitable organic template (Figure 1). The corrosion protection characteris-tics were investigated with thin epoxy-based CeO2 interlayer coatings on alu-minum alloys.

Synthesis, processing and use of particles

A printable read & write memory based on ferroelectricity (FRAM) was developed in the frame of the EU pro-ject PriMeBits (Figure 2). To facilitate low voltage operation, a requirement of printed electronics, the low coer-cive fields of ferroelectric ceramics like

Introduction

The primary focus of the Program Di-vision Nanoprotect is to investigate novel inorganic, organic and hybrid na-nocomposite materials. In this context, the three independent components – nanoparticles, matrix forming binders and surface modificators – are com-bined to make new nanocomposites with innovative properties. In 2010, specific attention has been given to the development of environmentally benign protection systems for met-als, wood and concrete. Furthermore materials were investigated according to energy saving potential in indus-trial processes. The development of processing pathways for the assembly of special functional particulate struc-tures for printable electronics was also studied. The project of synthesizing bioactive surface modificators for na-noparticles completed the field of ac-tivity.

During 2010 the Program Division was active in four publicly funded projects. The EU project PriMeBits focusing on particles for printable electronics and the EraSME project UNACON on ce-ment additives were finalized at the end of the year. The BMBF project EcoRepair was continued into 2010. In this project Nanoprotect and the Pro-gram Division Optical Materials collab-orated on the development of energy-saving repair techniques for ceramic products. The DFG project in coopera-tion with the University of Tübingen was also continued from 2009; the topic of the project is the development of nanoparticles with bioactive surface modifiers and an investigation of their interaction with biological systems. Finally, an industrial project on corro-sion protection coatings for steel was continued in 2010.

In the second half-year a task-force “Biogenic materials” has been set up with the objective of an investigation on potential and limitations of bio-genic materials via biomineralization. An interdisciplinary team of biochem-

Figure 1: SEM image of an epoxy-based CeO2-interlayer coating on an aluminum alloy.

Figure 2: Fully gravure printed memory cell (printed by VTT with INM material).

53

Binder and additi ve development

In 2010, the UNACON project (BMWi funded European project in the Er-aSME program) was fi nalized. The objecti ves of this project were the development of a hydrophobising na-nocomposite and a phase changing material containing nanocomposites for concrete mix. By immobilizati on of the SiO2-part of the nanocomposites in the CSH matrix via a pozzolanic re-acti on a long term stability of the hy-drophobising eff ect and of the thermal buff er behavior in concrete goods was envisaged. A homogeneous miscibil-ity of the nanocomposites in the liq-uid concrete mixtures combined with excellent hydrophobising and thermal buff er properti es could be achieved. As second eff ect a signifi cant retarda-ti on of the curing ti me was observed. Both nanocomposites caused a sig-nifi cant reducti on of the mechanical strength in concrete goods. A cause study disclosed an infl uence of the mass distributi on of the additi ves. Freshly prepared additi ves showed a broad molar mass distributi on (Figure 3). Aft er aging of the additi ves molar masses with a higher average mass

BaTiO3 were exploited. The polymeric consistency of printed electronics and the related processes does not allow thermal sintering of ceramics, but their uti lizati on in the form of parti cles in composites is possible.

At INM, several batches of ferroelec-tric BaTiO3 parti cles with a size range between 40 and 140 nm were syn-thesized. Memory cell samples were fabricated from these as well as from other commercial parti cles, primarily by wet coati ng methods using pastes and dispersions with variati ons of mi-crostructures and consti tuents. These experiments resulted in relati ons be-tween synthesis, microstructure and properti es for parti cles as well as for memory cells.

It was found that the memory cell com-posites could be polarized ferroelectri-cally despite the fact that most of the parti cles were embedded in the dielec-tric matrix, i.e. not in direct contact to the electrodes. The ferroelectric prop-erti es of the composites diff ered to ce-ramics with regard to coercive fi elds, saturati on and retenti on.

Detailed results were published and presented by the INM PriMeBits team in 2010 in a journal arti cle and at fi ve conferences, seminars and workshops. A large batch of a ferroelectric printi ng paste was prepared for a pilot print-ing experiment at VTT to demonstrate scalability. These printed memory structures were exhibited on the INM booth at the Hannover Industrial Fair. In May 2010 INM hosted one of the technical PriMeBits meeti ngs in Saar-brücken.

The PriMeBits project (coordinator: VTT, Finland, 2008 - 2010) was suc-cessfully concluded. The WORM mem-ory development resulted in the public presentati on of demonstrators with commercializati on potenti al. Ideas for further applicati ons of both memory types were published. For further in-formati on, refer to the project website www.primebits.eu.

Figure 3: Size Exclusion Chromatography: Mass distributi on of an additi ve for concrete before (black) and aft er arti fi cial aging treatment (red).

0 5 10 15 20 25 30

-10000

-5000

0

5000

10000

15000

346g/mol

451g/mol

3076g/mol

>10700g/mol

before aging after aging

Ref

ract

ive

inde

x

Retention volume in [ml]

54

derivative was used. After covalent coupling of the carbohydrate deriva-tive on the particles surface interac-tions with proteins on the membrane of erythrocytes can be investigated.

Outlook

In 2011, the BMBF project EcoRepair and the DFG project in cooperation with University of Tübingen will be con-tinued. The work will also be directed to answer fundamental questions, aiming at the development of innovative mate-rials and publications. Key investigative aspects will be ferroelectric behavior of particulate structures. In this context, the polarization and depolarization be-havior of small ferroelectric particles are of special interest. Nanoparticle processing will be studied to develop functional particulate structures, e.g. for the field of printed electronics.

An additional topic to be investigated in 2011 comprises Sol-Gel-based mate-rials with a low volatile organic content and with aging stable properties. The Program Division will work on the de-velopment of VOC guideline conform-ing sol-gel matrix materials which are of interest for eco-friendly protection coatings with self healing characteris-tics.

Finally, the development of bioactive surface modifiers for physicochemi-cal and biochemical modifications of drugs and nanoparticles will be inten-sified. The utilization of these features should serve to arrange nanoparticles and surfaces with pharmacodynamic and medical technical properties like drug targeting or improved biocom-patibility.

distribution resulted – combined with a smaller influence on the mechanical strength in concrete goods.

As a second publicly funded project, the BMBF project Ecorepair was continued together with the INM Program Divi-sion Optical Materials and three Ger-man SME’s. The objective of this project is the development of a new material for the repair of glaze on ceramics at temperatures below the quartz inver-sion. Our function in this project is the development of a low temperature sintering binding matrix based on the proved nanobinder concept (www.ecorepair.info). At midterm, a new na-nobinder system with a prolonged cur-ing progress was developed. Mechani-cally hard materials containing some fillers were synthesized after low tem-perature curing at 550°C and featured excellent adhesive and cohesive charac-teristics.

Synthesis of bioactive surface modificators

In a DFG project with the University of Tübingen, INM developed special nano-particles without as well as with bioac-tive surface modifications. In Tübingen, the interactions of these nanoparticles with the membrane of erythrocytes, their effect on signal transduction mechanisms in erythrocytes and their potential as drug carrier in monocellu-lar parasites are explored.

SiO2- and Fe2O3-nanoparticles as well as core-shell particles with various size distributions were prepared and char-acterized (Figure 4). The development of a special carbohydrate-surface modificator was conducted in parallel. As carbohydrate structure a sialic acid

Figure 4: TEM picture of core-shell Fe2O3-SiO2-nanoparticles.

55

durch doti erte Metalloxidmateriali-en, sowie zur Prozesstechnik wurden durchgeführt.

• Ionische Flüssigkeiten: Sie wurden bei der Synthese anorganischer Materi alien vornehmlich für die Herstellung von TiO2 und ZrO2 ein-gesetzt. Die Methode lieferte neue Erkenntnisse zur Prekursorchemie und erwies sich als ein interessantes alternati ves Werkzeug zur Synthese nanoskaliger Materialien.

• Opti sches Kompositmaterial: In dem Projekt wurde ein transparentes Ma-terial mit einem Brechungsindex von über 1,7 und einer gleichzeiti gen Re-sistenz gegen eine Temperatur von 250 °C über 5 Minuten entwickelt. Dieses sollte für den Einsatz in einem Prägeprozess kleiner Kameralinsen verwendbar sein. Die Ziele wurden mit einem Kompositmaterial auf Basis von Zirkonoxid und einer Acrylverbin-dung erreicht (AiF-Projekt PROLINSE).

• Ontologie der Nanotechnologie: In dem vom Leibniz SAW Fonds geför-derten Projekt wird eine Ontologie zur Chemischen Nanotechnologie entwi-ckelt. Dabei leistete das INM neben der inhaltlichen Gestaltung wichti ge Beiträge zur Populati on der Ontolo-

Der Programmbereich Opti sche Mate-rialien beschäft igt sich mit Synthese-, Applikati ons- und Strukturierungs-techniken zur Erzeugung strukturier-ter Oberfl ächen, Beschichtungen und Materialien mit besonderen opti schen und elektrischen Eigenschaft en.

Im Jahr 2010 hat der Programmbereich Opti sche Materialien seine Akti vitäten hauptsächlich auf Beschichtungen für Glas und Kunststoff e zur Anwendung auf dem Sektor Erneuerbarer Energi-en konzentriert. Die Forschung fokus-sierte auf Refrakti vindexmaterialien, Mikrostrukturierung, Anti beschlag-, mikrostrukturierte Silber- und Ionen-barriereschichten für CIGS-(Copper-Indium-Gallium-Selenid)-Dünnschicht-solarzellen. Kooperati onen mit der Universität des Saarlandes sowie mit anderen Programmbereichen des INM wurden verstärkt, so mit CVD/Bioober-fl ächen auf dem Gebiet der CIGS Dünn-schichtsolarzellen und mit Funkti onelle Oberfl ächen zum Up-scaling von Mikro-strukturen mit hohem Aspektverhältnis zur Verbesserung der Oberfl ächenhaft -eigenschaft en durchgeführt.

Vorrangige Akti vitäten des Programm-bereichs umfassten:

• Erneuerbare Energien: Für CIGS-Solarzellen wurde eine Schicht ent-wickelt, die die Eindiff usion von Eisenionen verhindert, gleichzeiti g Natriumionen liefert, die Effi zienz der Solarzelle steigert und als Isola-ti onsschicht gegen das Substrat fun-giert. Einen weiteren Schwerpunkt bildeten poröse Anti refl exschichten auf Basis von SiO2/TiO2 Kern-Schale-Nanoparti keln zum Einsatz auf Solar-zellen.

• Transparente Elektroden auf der Basis von ITO (Zinn-doti ertem Indi-umoxid): Sie wurden durch Einsatz eines halbleitenden Metalloxids, das die Bindephase teilweise substi tu-ierte, in Richtung verbesserter Ma-trixleitf ähigkeiten weiterentwickelt. Experimente zum Ersatz von ITO

Opti sche Materialien / Opti cal Materials

Dr. Peter William de Oliveira

gie, zur Annotati on von Texten und zur Bewertung der über Textmining gene-rierten Terme (SAW-Projekt NanOn).

• Reparatur von Keramikglasuren: Im Projekt wurde erfolgreich an der Entwicklung eines Systems zur Repa-ratur kleiner Oberfl ächenschäden in Keramikglasuren bei ti efen Tempe-raturen gearbeitet. Hierbei spielten die Anpassung der opti schen und hapti schen Oberfl ächeneigenschaf-ten, sowie eine hohe chemische und mechanische Stabilität eine wichti ge Rolle. Die Ziele sollen durch ein Hy-bridmaterial mit organisch funkti o-nalisierten und polymerisierbaren Silanen und weiteren metallorgani-schen Bindephasen realisiert wer-den (BMBF-Projekt EcoRepair).

• Leitf ähige Silbermikrostrukturen: Die bisher entwickelte Methode wurde um die Prägung UV-transpa-renter Materialien erweitert, was eine großfl ächige Strukturierung von Polymerfolien in einem konti nuier-lichen Prozess erlaubt. Es wurden periodische Primärstrukturen im Be-reich einiger Mikrometer bei gleich-zeiti gem Auft reten von sub-µm Se-kundärstrukturen erzeugt.

56

such as steel foils, the cell efficiency is affected by substrate ions such as iron diffusing into the absorber layer. Fur-thermore, a conductive substrate pre-vents the fabrication of monolithically integrated modules by the serial con-nection of several cells on the same substrate. To solve these issues, glass-like sol-gel thin films were coated on steel substrates before fabricating the solar cells on top. These have a triple functionality: firstly, they are acting as a barrier against the diffusion of transi-tion metal ions, secondly, they serve as a diffusion source for sodium, which is known to be a beneficial dopant, and finally, they provide an electrical insu-lating layer. The focus of this work was the electrical insulation properties of the films, which were found to be suf-ficient for integrating smaller modules comprising up to 100 individual cells. A closer investigation of the residual conductivity at low voltages and sub-Hz frequencies revealed clear indica-tions that the conductivity is mostly ionic and that, depending on the pro-cessing parameters, absorbed water potentially plays a major role.

The results of SIMS (secondary ion mass spectroscopy) measurements are sum-marized in Figure 1. It was confirmed that the sol-gel film is an effective bar-rier against the diffusion of transition metal ions and a highly effective source of sodium. CIGS solar cells fabricated on steel substrates with barrier coating showed a performance similar to cells fabricated on glass as a reference.

2) Single layer porous antireflective coatings for solar cells: From a sol with functionalized core/shell SiO2/TiO2 na-noparticles, an antireflective coating with a transmittance of 98% at 550 nm was obtained by means of dip-coating on a 2.5 mm thick glass of size 50 x 50 cm². A single layer coating (with thick-ness between 100 and 140 nm) im-proves the average transmittance of

The research of the Program Division Optical Materials is focussed on the de-velopment of materials with particular properties combined with application methods to produce multifunctional coating on glass or plastic substrates.

In 2010, the Program Division Optical Materials concentrated its activities mainly on the development of materi-als and techniques for coatings on glass and plastics for applications in the re-newable energy sector. Its research focused on the development of mate-rials and methods for applications like low and high refractive index materi-als, micro-patterning, anti-fogging-, silver micro-patterned- and ion bar-rier coatings for CIGS (Copper-Indium-Gallium-Selenide) thin solar cells. The cooperation with the Saarland Univer-sity and with other INM Program Divi-sions was strengthened: with the Pro-gram Division CVD/Biosurfaces in the development of CIGS thin solar cells manufactured by a combined sol-gel and chemical vapor deposition tech-nique, and with the Program Division Functional Surfaces in a joint task force on the up-scaling of high aspect ratio micro-patterning for the improvement of adhesive properties.

Principal activities of the Program Di-vision Optical Materials in 2010 com-prise:

Materials for renewable energy applications

One focus were sol-gel thin films pro-viding diffusion barrier functionality and electrical insulation for Cu(In,Ga)Se2 solar cells on steel substrates. An-other focus was self-cleaning antire-flective coatings for solar cells.

1) Cu(In,Ga)Se2 is a material success-fully used for thin-film solar cells when deposited on glass substrates. How-ever, on low cost flexible substrates,

Figure 1: SIMS depth profiles through CIGS/Mo on a steel substrate with barrier, on a steel sub-strate without barrier, and on a glass reference.

Figure 2: UV-VIS transmittance spectrum of un-coated glass and coated glass with a porous sin-gle antireflective coating.

57

and ATO (anti mony-doped ti n oxide). So far no suitable candidate for the replacement of ITO has been found. However the eff orts in this directi on will be conti nued. Direct doping of ITO with Ag and Au, respecti vely, was also investi gated, but led only to minor im-provements of the conducti vity. The work on the opti mizati on of the pre- and post-treatment focused on the use of short high-temperature treat-ments followed by recovering sintering treatments and subsequent reducti on treatments. The processes investi -gated were able to improve samples with an imperfect microstructure but yielded no signifi cant improvements on samples of already high quality.

Ionic Liquids in Synthesis of Inorganic Materials

Mediated by ionic liquids with alco-holic solvent, anatase nanoparti cles with various morphologies were syn-thesized under solvothermal condi-ti ons. We investi gated the hydrolysis reacti ons of Ti(OiPr)4 in the presence of various ionic liquids. In the presence of [BMIM][BF4], [BMIM]2[Ti(OH)6] was ob-tained as an anion exchange reacti on product. Ti7O4(OEt)20 was obtained in another anion ionic liquid, playing a key role in the nanostructure formati on under solvothermal reacti ons. In con-trast to ti tanium, zirconium alcoholate gives rise to more complex results. We have developed a method to synthe-size stable hexahydroxometalate (Ti or Zr) or pentahydroxozirconate salts.

Opti cal composite materials

In 2010 a transparent material with a refracti ve index of 1.7 or higher and a temperature resistance against 250°C for 5 minutes was developed. The ma-terial also had to be suitable for an em-bossing process for the preparati on of

the low iron glass substrate by about 5% in the spectral range between 380 nm and 1200 nm (Figure 2). The broad range of the anti refl ecti ve eff ect makes this coati ng att racti ve for use in solar energy applicati ons. Pencil tests showed that the scratch resistance of the coated glass can reach 6 H. The adhesion has been determined by a crosshatch tape test, resulti ng in a very high adhesion value of 5.

Transparent conducti ve coati ngs

The conducti vity of wet chemically de-posited ITO coati ngs was improved by an enhancement of the matrix conduc-ti vity. The binder consisted of an insu-lati ng component and an electronically conducti ve component, e.g. a semicon-ducti ng metal oxide (MOx, e.g. TiO2). The concentrati on of the metal oxide in the binder phase was varied and the sheet resistance, transmission and haze were investi gated as a functi on of the MOx concentrati on. With increas-ing MOx content up to a certain limit, the sheet resistance and the resisti vity were reduced (Figure 3). In additi on, haze and transmitt ance were improved and the UV hardening was accelerated by additi on of the metal oxide to the binder matrix. The sheet resistance of printed MOx /ITO coati ngs on foil aft er hardening under UV-irradiati on could be decreased from 1520 Ω/sq (ITO coati ng) to 350 Ω/sq or 0.098 Ωcm (87% transmission in the visible range, 2% haze). Furthermore, the increase of the sheet resistance with ti me (“aging behavior”) was reduced by using MOx/ITO coati ngs. Possible applicati ons for the printed ITO and MOx/ITO fi lms are e.g. touch screen panels, electrodes for optoelectronic devices and printed electronics.

For the replacement of ITO, suspen-sions containing Au and Ag were com-bined with AZO (Al-doped zinc oxide)

Figure 3: Sheet resistance, resisti vity, total transmitt ance (Tt), haze and thickness of ITO coati ngs on glass aft er UV treatment (23.4 J/cm2) and aft er UV treatment and additi onal thermal treatment (250°C, air, 30 min) as a functi on of the MOx/ITO concentrati on. The sheet resistance R/sq was measured 5 min aft er the last UV-treatment and thermal treatment respecti vely.

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Repair of ceramic surfaces

In cooperation with the Program Divi-sion Nanoprotect the project was suc-cessful in developing an innovative low temperature repair system for small surface faults which frequently show up in the glaze of ceramics during fir-ing. Currently, such faults are milled, refilled with new glace material and re-fired at 1200°C, which is a very energy-consuming method. The targeted low temperature repair material was re-quired to have the optical appearance and haptics of the surrounding glaze as well as its chemical and mechanical sta-bility. Currently, a repair system based on an organic-inorganic hybrid material contains organically functionalized and polymerizable silanes, as well as further metal organic compounds as the binder phase. The development will continue optimization of the application process in collaboration with project partners (BMBF-project EcoRepair).

Conductive silver micro patterns

In 2010 we extended the silver micro patterning technique by using UV-transparent stamps instead of a photo-mask. This allows large scale pattern-ing of polymer foils in a continuous high-speed process. The silver-com-plex containing liquid is displaced by the embossed patterns of the stamp so that silver structures can only form in between, when irradiated with UV-light. Up to now, laboratory samples with structures from 5 µm up to 100 µm have been made. The successful periodic patterns can be visualized by laser diffraction and scanning electron microscopy, as shown in Figure 5.

The process is used for the micropat-terning of metal surfaces to investigate the mechanical properties in coop-eration with the new Junior Research Group Metallic Microstructures.

small lenses for the application in mo-bile phones. Preparation of a material based on zirconium oxide and an acryl-ic resin that met these requirements was successful. Further experiments led to a material suitable for the prepa-ration of lenses with a moth eye struc-tured surface resulting in antireflective properties, depicted in Figure 4. (Pro-ject PROLINSE (AiF, KF2024301AB8))

Ontology of nanotechnology

This project funded by Leibniz SAW funds is supposed to result in an ontol-ogy that covers chemical nanotechnol-ogy. INM provides scientific expertise to this project. An important task in 2010 was the population of the ontolo-gy with more classes and terms. There-fore the annotation of texts was per-formed at INM and a list of more than 6000 terms generated by text mining was evaluated. (Leibniz SAW project NanOn)

Figure 4: SEM micrograph of the surface of an embossed micro lens with a porous antireflec-tive surface.

Figure 5: Interference pattern of a Ar+ ion laser of a silver micro grid for optical quality control.

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gestellt, dass zwischen hoher und niedriger Haft kraft durch Variati on des Anpressdrucks geschaltet wer-den kann.

• Grenzfl ächen- und Größeneff ekte strukturierter Metalloberfl ächen: Un-tersuchungen an parti kelverstärkten metallischen Mikrostrukturen zeig-ten, dass Miniaturisierung zu einer ähnlichen Festi gkeitssteigerung führt wie aufwändige Legierungsbildung.

Um die Haft eigenschaft en natürlicher Adhäsionssysteme besser zu verstehen und nachzuahmen, werden die Auswir-kungen mechanischer Eigenschaft en strukturierter Polymere hinsichtlich ihrer Haft kraft untersucht. Weiterhin werden Adhäsionsexperimente an ein-zelnen makro- und mikroskopischen Haft strukturen durchgeführt. Die ge-wonnenen Erkenntnisse werden auf Verfahren zur großfl ächigen Herstel-lung von Geckohaft systemen ange-wendet.

Adhäsion und Deformati on von wei-chen Materialien wird weiter intensiv untersucht. Basierend auf den Ergeb-nissen und Forschungsarbeiten im Bereich schaltbarer und medizinischer Themen werden erfolgversprechende Anwendungsbereiche erschlossen. Ne-

Der Programmbereich Funkti onelle Oberfl ächen beschäft igt sich mit der Herstellung und Opti mierung von mik-rostrukturierten Oberfl ächen mit neu-arti gen mechanischen Eigenschaft en. Als Materialsysteme werden Elastomere und Metalle untersucht. Ziel ist die Er-forschung und Anwendung von größen-abhängigen Mechanismen, die die Ein-stellung neuer, vorzugsweise schaltbarer Oberfl ächenfunkti onalitäten erlauben.

Im Jahr 2010 wurden unter Anderem folgende Forschungsarbeiten durchge-führt:

• Multiskalen-Adhäsionsmessungen mit in situ-Visualisierung: Die be-stehenden Adhäsionsmessanlagen wurden mit in situ-Visualisierungs-funkti onen erweitert. Ein neues Ad-häsionsmessgerät für Messungen im Rasterelektronenmikroskop wurde in Betrieb genommen, das in situ-Visualisierung mit starker Vergröße-rung erlaubt.

• Up-scaling von Strukturierungsprozes-sen: Gemeinsam mit den Programm-bereichen Opti sche Materialien und Nanomere wurde an Verfahren zur großfl ächigen Strukturierung gearbei-tet, welche Anwendungen in groß-technischem Maß erwarten lassen.

• Treff punkt internati onaler Spitzen-forschung: Ein Workshop zum The-ma Gecko-Haft ung fand am INM statt , an dem hochkaräti ge Wissen-schaft ler aus aller Welt teilnahmen. In 2011 werden Prof. M. Sitti (Carne-gie-Mellon University, USA), Prof. A. Jagota (Leheigh University, USA) und Prof. A. Ghatak (IIT, Indien) als Gast-wissenschaft ler am INM arbeiten.

• Funkti onelle Oberfl ächen für medizi-nische Anwendungen: In Zusammen-arbeit mit der HNO-Klinik in Homburg wurden erste Studien durchgeführt, die das Haft potenti al von geckoins-pirierten Strukturen auf weichen und feuchten Oberfl ächen aufzeigen.

• Herstellung schaltbarer Haft struktu-ren: Haft strukturen wurden so her-

Funkti onelle Oberfl ächen / Functi onal Surfaces

Prof. Dr. Eduard Arzt

ben den bestehenden Forschungsthe-men werden neue Bereiche, vor allem multi funkti onelle Oberfl ächen mit zu-sätzlichen biologischen, mechanischen oder chemischen Funkti onen, in die Strategie des Programmbereichs Funk-ti onelle Oberfl ächen aufgenommen.

In 2010 wurden diverse Projekte mit anderen Programmbereichen des INM durchgeführt. Gemeinsam mit dem Programmbereich Biomineralisati on wurden die mechanischen Eigenschaf-ten von Perlmutt untersucht. Mit dem Programmbereich Opti sche Materiali-en wurde ein Verfahren zur großfl ächi-gen Herstellung von Geckostrukturen entwickelt und patenti ert. Gemeinsam mit der Servicgruppe Analyti k wurden neue Adhäsionsmessmethoden ent-wickelt. In Kooperati on mit dem Pro-grammbereich Nanotribologie wurden Kontaktphänomene mikrostrukturier-ter Oberfl ächen aufgeklärt. Diese Phä-nomene wurden dann gemeinsam mit dem Programmbereich Modellierung/ Simulati on auf theoreti scher Grundla-ge geklärt. Ab 2011 wird ein Teil der Ar-beiten in der neuen Juniorforschungs-gruppe Metallische Mikrostrukturen unter der Leitung von Dr. Andreas Schneider weitergeführt.

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Adhesion measurements with spherical and flat probes

The adhesion tester developed in the Program Division Functional Surfaces allows adhesion measurements with controlled alignment. Thus, it is pos-sible to perform adhesion measure-ments with flat probes. An extensive study of adhesion phenomena was conducted with flat and spherical probes on patterned PDMS surfaces. The results show that patterned sur-faces are more sensitive to misalign-ment than flat control samples, if measured using a flat probe (Figure 3). In addition, it was shown by comparing adhesion measurements from flat and spherical probes that the adhesion of patterned surfaces is underestimated if measured with a spherical probe. Both effects can be explained by the angle dependent adhesion of individu-al structures [E. Kroner, D. Paretkar, R. McMeeking, E. Arzt, accepted for pub-lication in The Journal of Adhesion].

Switchable adhesives based on micropatterned polymer surfaces

Different stimuli were explored to trig-ger geometrical or material dependent switching mechanisms. For the stand-ard material poly(dimethylsiloxane) it was found that fibrillar patterns ex-hibit a high adhesion at low preload, whereas high preload results in a loss of adhesion. In situ monitoring revealed that pillars buckle at a certain preload, thus losing contact with the probe. This leads to a significant drop in adhesion of several orders of magnitude in pull-off force [D. Paretkar, M. Kamperman, A. Schneider, D. Martina, C. Creton, E. Arzt, Mat Sci Eng C, published online (2010); see Paretkar et al. in this report].

The research activities in the Program Division Functional Surfaces are fo-cused on the investigation and devel-opment of bioinspired surface patterns on polymeric and metallic materials. Current research topics include under-standing of basic principles in mechan-ics of micro- and nanoscaled systems, adhesion phenomena of fibrillar struc-tures and the development of surfaces with multifunctional properties. There is also an effort to transfer the funda-mental findings to large scale produc-tion methods. Various research pro-jects in 2010 are highlighted:

Adhesion testing

The existing adhesion measurement system was expanded into an in situ ob-servation tool (Figure 1). This allows the simultaneous acquisition of force data and corresponding micrographs of the contact area. By this additional feature it was possible to improve the accuracy of our adhesion tester and to gain addi-tional mechanistic insight. For example, we are now able to detect phenomena like buckling effects of micropillars.

To increase the versatility of the meas-urement system an additional adhesion tester was set up in an environmental scanning electron microscope (ESEM). The system is based on a calibrated glass cantilever for force detection and on a micromanipulator for sample dis-placement. This system can be used to perform macroscopic experiments inside the ESEM but with a significantly increased lateral resolution. For single pillar adhesion tests, a PicoIndenter from Hysitron was set up, which allows high resolution force and displacement measurements (Figure 2).

Figure 2: ESEM image of the PicoIndenter probe approaching a single pillar in an adhesion test.

Figure 1: Photograph of the adhesion tester MAD 2 with integrated in situ visualization.

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alloys with diff erent chemical composi-ti on. Finally, we aimed to increase the aspect rati o of the structures by specifi c surface treatments, e.g. shot peening and surface mechanical att riti on [E. Qin, E. Arzt, A. Schneider, to be published].

Mechanical characterizati on of biomaterials

In collaborati on with the Program Division Biomineralizati on, we have recently started to perform mechani-cal tests on biomaterials. These ex-periments give insight into the design principles of natural systems and high-light the role of a multi -hierarchical structure for mechanical integrity. For example, we have performed na-noindentati on and microcompression experiments on nacre material from diff erent sea shell species (Figure 6). Experiments have demonstrated that the indentati on hardness and Young’s modulus increase from the interface calcite/aragonite to the inner surface of the shell. Nacre pillar compression tests in a dry environment have shown a britt le behavior, independent of pillar

Patt erned surfaces for biomedical applicati on

A promising fi eld of applicati on for dry adhesives is the development of new implant materials. While bioinspired ad-hesives are usually designed to adhere to rigid surfaces, biomedical applicati ons require adhesion on wet, living and soft materials. Besides the adhesion proper-ti es, additi onal functi ons such as biodeg-radability or controlled cell growth are of relevance. To simulate these conditi ons, we developed model systems based on gelati n and glycerol water mixtures with mechanical properti es comparable to human ti ssue. In additi on to adhe-sion tests, fi rst cell growth experiments were performed together with the De-partment of Otorhinolaryngology at the Medical Faculty of the Saarland Univer-sity, Homburg (Figure 4). The preliminary results are very promising and will be expanded in the future.

Metallic shape memory surfaces

The indentati on induced two-way shape memory eff ect in Nickel/Tita-nium (NiTi) surfaces was investi gated in order to obtain a material with thermal-ly switchable surface structures (Figure 5). Indentati on tests were performed with a systemati c variati on of indenter shape, distance between the indents and applied load over several orders of magnitude. The results show that the deformati on of the switchable struc-tures strongly depends on the indenta-ti on parameters. Focus ion beam assist-ed transmission electron microscopy and electron back scatt ered diff racti on were used to analyze the microstructur-al evoluti on and the size of the stressed fi eld below the indents. These experi-ments highlight that the plasti cally de-formed zone determines the size of the evolved structure. To adjust the switch-ing temperature of the material, various heat treatments were applied to NiTi-

Figure 3: Angle dependent adhesion of a patt erned surface with structure diameter of 4.7 µm and a structure height of 0.82 µm.

Figure 4: Future aim: “gecko” surfaces could be used for repair of ti ssue, e.g. the ear drum.

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The research field of metallic micro- and nanostructures resulted in the formation of a new Junior Research Group Metallic Microstructures led by Dr. Andreas Schneider, which will be established in 2011. The Program Divi-sion Functional Surfaces will be headed by Prof. Dr. Eduard Arzt and Assistant Group Leader Dipl.-Ing. Elmar Kroner.

The newly formed Junior Research Group Metallic Microstructures aims to build a know-how base of the me-chanics and functions of modern me-tallic materials, thin films and nano-structures. One of the main goals is the understanding of the plasticity in metallic micro- and nanostructures. A collaboration with the Structural Metallic Materials Group of Prof. Da-vid Dunand from the Northwestern University, Chicago USA, is already es-tablished. At the same time, the new research group will develop micro- and nanopatterning techniques in order to functionalize metal surfaces. Together with the Program Division Biominer-alization, the new research group will continue the mechanical characteriza-tion of multi-hierarchical biomaterials. Compression tests will be performed on nacre micro- and nanopillars with various orientations with respect to the platelet structure of the shell.

Our overall strategy is to advance the understanding and to improve the control of the properties of micro- and nanostructured surfaces. Ultimately, we aim to contribute substantially to the development of multifunctional surfaces with tunable properties. Such surfaces may find widespread applications ranging from household items and construction devices to biomedical devices and microtechnological systems.

size. However, higher fracture stresses were observed for smaller pillar di-ameters. Compression tests on pillars submerged in different liquids pillars are planned and will help to under-stand the role of the organic matrix at the interface between the nacre plate-lets [N. Peter, I. Weiss, B. Heiland, E. Arzt, A. Schneider, to be published].

Outlook

In 2011, the research activities of the Program Division Functional Surfaces will be extended to include adhesive materials for biomedical application. In collaboration with the Department of Otorhinolaryngology at the Medi-cal Faculty of the Saarland University, Homburg, multi-functional implant materials will be addressed. Besides the pressure-switchable adhesives, new adhesives triggered by different stimuli will be investigated. A further research field for introducing bioin-spired adhesives into applications will be the fabrication of hierarchical adhe-sion systems. The special mechanical properties of hierarchical structures are believed to be superior to single-level adhesives if tested against rough surfaces. This research field will be conducted together with the Junior Research Group Structure Formation where new particle based fabrication approaches will be realized.

Figure 6: Focused ion beam machined nacre pil-lar with a top diameter of about 1 µm.

Figure 5: Demonstrating the principle of shape memory surfaces: White light interferometry mea-surements of shape memory surface a) heated to 100°C, and b) cooled with liquid nitrogen.

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men von Polymerkompositmaterialien mit dem Programmbereich NMO.

Einige ausgewählte Beispiele verdeutli-chen den Fortschritt im Jahr 2010:

• Es wurde ein neuarti ges Instrument für Reibungs- und Indentati onsmes-sungen auf molekularer, mikrosko-pischer und makroskopischer Skala gebaut, bei dem die Probe mit Mi-krometerpräzision zwischen den Messstati onen verfahren werden kann. Erste Reibungsmessungen sind auf den Blätt ern der Tabakpfl anze durchgeführt worden.

• Atomare Reibungsmessungen auf reinen Metalloberfl ächen haben ge-zeigt, dass durch die Bildung eines kristallinen metallischen Kontakts ein Regime von extrem niedriger Rei-bung entsteht.

• In Kratzversuchen auf kristallinen Proben hat sich herausgestellt, dass selbst im Nanometerbereich plas-ti sche Verformung einen wichti gen Beitrag zur Ausformung des Kratzers leistet.

Der Programmbereich Nanotribologie erforscht mechanische Materialeigen-schaft en aus grundlagenorienti erter Sichtweise und konzentriert sich dabei auf mikroskopische Mechanismen. Mit unseren Ergebnissen wollen wir zum Verständnis von Phänomenen wie Rei-bung, Verschleiß und Haft ung sowie zur wissensbasierten Entwicklung neuer Materialien mit speziellen mechani-schen Eigenschaft en beitragen. Unsere experimentellen Projekte basieren auf unserer Experti se in der hochaufl ösen-den Rasterkraft mikroskopie, die wir sowohl im Ultrahochvakuum als auch unter elektrochemischer Kontrolle ein-setzen. Außerdem entwickeln wir neue experimentelle Methoden, um me-chanische Eigenschaft en auf verschie-denen Längenskalen zu untersuchen. Anwendung fi nden unsere Methoden und Ergebnisse in Zusammenarbeit mit Partnergruppen, insbesondere am INM. Beispiele dafür sind gemeinschaft liche Untersuchungen zu den Grundlagen der Kratzfesti gkeit mit dem Programmbe-reich Nanomere, zu den mechanischen Eigenschaft en biologischer Materialien mit dem Programmbereich Biominera-lisati on, sowie zu Verschleißmechanis-

Nanotribologie / Nanotribology

Prof. Dr. Roland Bennewitz

• Unsere Beobachtungen zur extrem niedrigen Reibung auf Graphen ha-ben zur Gründung eines Forschungs-verbundes geführt, der mit Förde-rung des BMBF untersucht, ob die Schmierung durch Graphen auch auf makroskopischer Ebene und damit eventuell in technologischen An-wendungen gelingt.

Der Programmbereich Nanotribologie wird seine Arbeiten zu den mikroskopi-schen Mechanismen von Reibung und Verschleiß fortf ühren. Dabei werden Temperatureff ekte und die Schaltbar-keit von Reibung durch elektrochemi-sche Oxidati on im Mitt elpunkt stehen. Der von uns aufgebaute Multi skalen-tester wird für das Studium biologi-scher und biomimeti scher Materialien eingesetzt. Die Anwendung unserer Ergebnisse mit unseren Partnern wird sich auf die weitere Entwicklung von Kompositmaterialien und die Perspek-ti ven schaltbarer mechanischer Eigen-schaft en konzentrieren.

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The Program Division is well connected also externally, for example with the University of Basel, Switzerland, the Karlsruhe Institute of Technology, and McGill University in Montreal, Canada. A particularly strong exchange of ideas and results is enabled by the active participation in the Eurocores Program “Friction and Adhesion in Nanomechan-ical Systems” of the European Science Foundation. Its annual conference 2010 was organized in Saarbrücken by the INM and chaired by Roland Bennewitz.

Mechanical testing at different length scales

In 2010 we have started the project on “Multi-scale mechanical behavior of hierarchically structured biological and technological materials”, which is funded in the SAW scheme of the Leibniz Association. The particular me-chanical properties of materials with structural elements from molecular to millimeter length scales are being studied. We have constructed a dedi-cated instrument for indentation and friction measurements on three differ-ent length scales (Figure 1). Samples are moved between the three meas-urement stations such that the very same area of interest can be tested at all length scales. First friction experi-ments on tobacco leaves have demon-strated the success of this instrumen-tal development. At the same time, we employed instrumented nanoinden-tation to apply the concept of multi-scale testing to bio-inspired fibrillar adhesives. Comparing the adhesion of single fibrils and of many fibrils, the contribution of the elastic backing lay-er to the mechanical properties could be revealed (G. Guidoni et al., Journal of the Mechanics and Physics of Solids 58 (2010) 1571).

Introduction

The Program Division Nanotribology explores the mechanical properties of materials from a fundamental perspec-tive with a focus on microscopic mecha-nisms. With our results we want to con-tribute to an understanding of phenom-ena like friction, wear, or adhesion and to a rational design of novel materials with certain mechanical functions. Our experimental projects rely on our exper-tise in the field of high-resolution force microscopy, which we apply in ultra-high vacuum and electrochemical environ-ments. Furthermore, we develop new experimental methods for mechanical testing on different length scales. The methods and results of fundamental nanotribology are applied in collabora-tions, in particular within the INM. Exam-ples are joint projects with the Program Divison Nanomers on the principles of scratch resistance, with the Biominerali-zation on mechanical resting of biologi-cal materials, and with the NMO on wear phenomena in polymer composites.

Figure 1: Photograph of the home-built multi-scale mechanical testing experiment. The atomic force microscope (AFM) is sensitive to molecular forces, the Micro Tester to adhesion forces of micrometer-sized elements, and the Milli Tester to adhesion and friction of whole structures at the millimeter scale. The sample can be moved between the three instruments with micrometer preci-sion. Two optical microscopes with crossed optical axes allow for a selection of areas of interest even on rough biological samples.

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experiments indicate that the plasti c mechanisms are not only enhanced at higher normal loads but also at slower scratching velociti es. The fricti on coef-fi cients measured during scratching are of the order of 0.3, closer to typical mac-roscopic values than to the extremely low fricti on coeffi cients found in AFM experiments in the non-wear regime (P. Egberts and R. Bennewitz, Advances in Science and Technology 64 (2010) 25).

Fricti on on epitaxial graphene layers

Graphene is a fascinati ng novel two-di-mensional material. The discoverers of its preparati on have been awarded the Nobel Prize in physics in 2010. We are interested in the fricti onal properti es of graphene, as it is the building block of the well-established solid lubricant graphite. We found that even a single layer of graphene is a good lubricant. As an example, fricti on force micros-copy measurements of the surface of a

Microscopic Fricti on Studies on Metal Surfaces

In one project, building on the strengths of high-resoluti on force microscopy in vacuum, the fricti onal properti es of metal surfaces were investi gated. Atomically fl at and clean metal surfaces exhibit a regime of ultra-low fricti on at low normal loads. Fricti on force micros-copy on Cu(100) and Au(111) surfaces revealed a clear atomic sti ck-slip mod-ulati on in the lateral force but almost zero dissipati on. Signifi cant fricti on was observed only for higher loads to-gether with the onset of wear. Usually, such low fricti on is explained in terms of thermal acti vati on. Our new results indicate that a compliant metallic neck between ti p and surface is formed which brings upon a low, load-inde-pendent shear stress. This project has been carried out by Dr. N. N. Gosvami, who worked at the INM as postdoctoral fellow supported by the Alexander-von-Humboldt-Foundati on (N. N. Gosvami et al., Tribology Lett ers 39 (2010) 19).

Fundamental studies of wear processes

Moving from the special case of wear-less sliding to higher loads, surfaces will be scratched. We observed that plasti c deformati on plays a signifi cant role in the mechanism of scratching wear at the nanometer scale in KBr single crystals. The nucleati on and subsequent moti on of screw dislocati ons leave monatomic steps on the surface which form the edges of monatomic terraces. These ter-races are formed next to the scratch and become part of the pile-up of material. Additi onal irregular pile-up is likely due to the diff usion of KBr molecules which were released by the scratching ti p. Edge dislocati ons are also produced in the course of scratching. They intersect the surface at a distance of some tens of nanometers from the scratch and can be recognized as weak topographic hill-ocks in non-contact AFM imaging. Our

Figure 2: Topography and fricti on of a SiC(0001) surface parti ally covered by an ultrathin layer of graphene (blue regions). The step structure is revealed by the perspecti ve view, while the fricti on signal is encoded in the color of the surface. The graphene fi lm was grown by thermal decompo-siti on of the SiC surface in ultra-high vacuum. The step height between the SiC terrace and the adjacent graphene terrace is about 0.35 nm, the step height between adjacent graphene terraces is about 0.5 nm.

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SiC(0001) crystal which is partially cov-ered with an ultrathin graphene film are presented in Figure 1. The topography shows the typical structure of terraces and steps of the SiC substrate after an-nealing in ultra-high vacuum. It is impos-sible to determine from the topography image which parts are covered by the graphene film. The friction signal, how-ever, shows a clear contrast between the SiC surface (high friction, encoded red) and the graphene film (low fric-tion, encoded blue). Graphene is mostly found on lower terraces in agreement with the growth process of thermal decomposition and silicon desorption. Besides the SiC areas, increased fric-tion is also observed at the steps. This well-known effect can be attributed to the increased tip–sample interaction at the steps. The friction signal in Figure 2 also serves as a demonstration for the resolution capabilities of force mi-croscopy on heterogeneous surfaces, which is limited only by the contact size between tip and surface (R. Bennewitz et al., Advanced Engineering Materials 12 (2010) 362). Our demonstration of

lubricity on graphene at small scales led to a collaboration with researchers in Saarbrücken, Karlsruhe, and Freiburg for an evaluation of graphene as novel tribological material, which is funded by the BMBF since summer 2010.

Outlook

The Program Division Nanotribol-ogy will continue to explore frictio-nal mechanisms at the atomic scale. Of particular interest are now effects of temperature and the prospects of switching friction on and off by exter-nal control, namely by electrochemical oxidation of surfaces. The multi-scale instrument which is now operational will be applied to biological and bio-mimetic materials. Application of our results in collaborations will focus on the further development of composite materials with unique mechanical pro-perties. In particular, we collaborate with the Program Division Nanomers in developing scratch-resistant nano-particle-reinforced polymer materials.

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zusammen, um Überstrukturen auf ver-schiedene Materialprobleme anzuwen-den. Solche Anwendungen reichen vom Ersatz opti scher Lithographie bis hin zu nanostrukturierten Ferroelektrika.

Im Jahr 2010 haben wir uns besonders mit der Abscheidung von Parti kelfi l-men aus Flüssigkeiten beschäft igt und die Rolle der Flüssigkeitsgrenzfl ächen im Detail studiert. Wir haben Nano-parti kel mit Hilfe von Emulsionen zu größeren „Supraparti keln“ angeord-net. Schließlich hat die Gruppe Nano-stäbchen hergestellt und untersucht, wie sie sich in Polymergelen verhalten.

Das Jahr 2011 wird weitere Entwick-lungen im Bereich der Nanoparti kel bringen, auf denen unsere Arbeit basiert. Außerdem werden wir Syn-chrotronstrahlung nutzen, um Anord-nungsprozesse der Nanoparti kel direkt beobachten zu können. Allgemein wird sich die Gruppe zunehmend mit Parti -keln beschäft igen, deren Interakti on zu neuen Funkti onen führt, weil Energie und Masse zwischen den Parti keln aus-getauscht werden.

Die Juniorforschungsgruppe Struktur-bildung auf kleinen Skalen untersucht die Anordnung kleiner Parti kel zu grö-ßeren Strukturen. Wir erforschen die Morphologie und Bildungsmechanis-men solcher Überstrukturen. Aus den Ergebnissen entwickeln wir Methoden, um Materialien auf kleinen Längenska-len zu strukturieren.

Unsere Forschung verbindet verschie-dene experimentelle Methoden. Wir nutzen chemische Synthese, um Na-noparti kel herzustellen und zu ver-ändern, die Streuung von Licht und Röntgenstrahlung, um ihre Bewegung zu beobachten, und Elektronenmikros-kopie, um die entstehenden Strukturen zu charakterisieren. Wir arbeiten mit Gruppen zusammen, die die Anordnung simulieren und theoreti sch beschrei-ben. So kombinieren wir grundlegende Fragen der Parti kelwechselwirkung und Mobilität mit technologischen Fragen der Parti kelabscheidung, Parti kelsta-bilität und Mikrofabrikati on. Parti kel-überstrukturen haben interessante Eigenschaft en. Wir arbeiten mit Grup-pen innerhalb und außerhalb des INM

Strukturbildung auf kleinen Skalen /Structure Formati on at Small Scales

Dr. Tobias Kraus

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Particle superstructures have interest-ing properties. We collaborate with groups inside and outside INM to ap-ply superstructures to different mate-rial problems. Applications range from the replacement of optical lithography to nanostructured ferroelectrics.

Convective assembly: enter the meniscus

Dip-coating is the gold standard for high-quality coatings from liquid sus-pensions. In dip-coating, particles are deposited in a random, uniform layer. Convective assembly adds order to this process. Much work has been done on the microscopic assembly mechanism that aligns particles in a dense film, but it remains challenging to deposit mac-roscopic, high-quality particle layers with convective assembly. Philip Born, a PhD student in the group, investi-gates why this ordering occurs.

Microscopically, convective assembly works because particles move depend-ing on the structure of the film depos-ited so far. Macroscopically, it depends on the exact shape of the meniscus the particle suspension forms on the substrate. We found that a deform-able, “slack” meniscus leads to better homogeneity in the film than a hardly deformable, “taut” meniscus. In situ observation of the assembly process in a dedicated setup with interference imaging allowed us to analyze this rela-tion in detail (Figure 1).

It turns out that defects can always form, but their consequences are far more dire with a taut meniscus. We thus optimized the processing condi-tions to deposit from a slack menis-cus. The resulting deposition process is fault-tolerant and robust and a step towards the practical application of convective assembly.

Mission

The Junior Research Group Structure Formation observes the arrangement of small particles into macroscopic structures. We study morphology and formation mechanisms of such super-structures. From these insights, we de-velop methods to structure materials at small scales.

Our research combines different ex-perimental methods. We use chemical synthesis to create and modify nano-particles, light and x-ray scattering to observe their dynamics, and electron microscopy to observe the resulting structures. We collaborate with simu-lation and theory groups to analyze the results. This research combines funda-mental questions of particle interac-tion and mobility with technological questions of particle deposition, parti-cle stability and microfabrication.

Figure 1: An optical micrograph showing the attempt to deposit an ordered layer of 500-nm-diam-eter polymer spheres. The deposition is plagued by defects. The meniscus that covers the bottom half of the image guides the transport of particles during assembly. The fringes in the meniscus are due to interference illumination and allow us to reconstruct its shape. Philip Born uses the recon-structed shape to analyze the formation of defects such as multilayers (top right and left) and holes (centre) and to prevent them in the future.

Figure 2: An electron micrograph of 6-nm-diameter gold nanoparticles that remained on the surface after the suspending toluene had evaporated. The particles are arranged into a dense monolayer.

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have applied for small-angle x-ray beam ti me at the European Synchrotron Radi-ati on Facility in Grenoble, where we will perform measurements in 2011. Hope-fully, the results will not only reveal the assembly mechanism, but also indicate how we can improve yield and quality of the resulti ng structures.

Rotati ng rods in generic gels

Usually, parti cles move in liquids and rest in solids. In 2010, a Canadian stu-dent, Annie Chen, visited us to analyze an intermediate case: nanoparti cles moving in a polymer soluti on during gelati on. The synthesis of gold na-norods proved crucial to this work.

It is hard to observe nanoparti cles inside a gel. Microscopy is unable to resolve the parti cle moti on, x-ray scat-tering is weak at our low parti cle con-centrati ons. We thus used a trick: opti -cally anisotropic parti cles that strongly aff ect the polarizati on of light as they scatt er it. Gold nanorods (Figure 3a) were synthesized by our technician Anika Weber, purifi ed and mixed into a hot agarose soluti on. Using “depo-larized dynamic light scatt ering” that is sensiti ve to the opti cal anisotropy of the rods, we obtained high-quality data on parti cle mobility while we cooled down the agarose.

More than monolayers at interfaces

Convecti ve assembly fails for very small parti cles with diameters below 10 nm. However, such parti cles oft en segregate to gas-liquid interfaces, where they form monolayers (Figure 2). We collab-orated with Saarland University’s Pat-rick Huber and a visiti ng student from England, John Aveson, to analyze this process. Originally, we had hoped to understand the mechanism bett er and then transfer it to a coati ng process.

However, it turned out that this seem-ingly simple process is complex. We showed in 2010 that surface tension drives segregati on, but were surprised to fi nd that segregati on does not stop at a monolayer: depending on condi-ti ons and even in equilibrium, multi ple strati fi ed layers fl oat at the interface. This is bad news for fabricati on (where one generally needs a conti nuous monolayer), but an intriguing result. What sets the number of layers? Do parti cles behave like a liquid that con-denses from the environment?

Supraparti cles

If parti cles segregate to the gas-liquid interface, it is not surprising that they also segregate to liquid-liquid interfac-es. In 2010, Johann Lacava, a PhD stu-dent in our group, was parti cularly inter-ested in fi nding whether nanoparti cles that are confi ned in emulsion droplets segregate to their surface. We already know that such parti cles can assemble into regular supraparti cles when the emulsion droplets shrink, but it remains unclear whether they start at the inter-face or in the bulk of the droplets. Ms. Lacava found that the average distance between the parti cles decreases as the emulsion droplets shrink, which hints at a bulk mechanism.

Her experiments also led to a reproduc-ible emulsifi cati on process. To further analyze the parti cles’ locati ons, we

Figure 3: Gold nanorods as shown in the transmission electron micrograph (a) were mixed into a hot soluti on of agarose. This soluti on was cooled down and the rods’ rotati on was measured using depolarized dynamic light scatt ering (b). A pronounced drop in mobility at a temperature of 36°C explains the change in the autocorrelati on functi ons at diff erent temperatures shown here.

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The results are intriguing. At high tem-peratures, agarose forms a solution in which the particles rotate freely. However, at a certain temperature the particles abruptly stop rotating – even though the solution still is a liquid (Fig-ure 3b). We will use this new method to develop materials in which the particles become mobile upon a certain stimulus.

Outlook

Emulsion droplets, nanoparticle ag-glomerates and unusual nanoparticles require advanced analysis techniques for their characterization. In 2010, we purchased and installed a Field-Flow Fractionation setup which we now ap-ply to analyze the supraparticles men-tioned above for example. In addition, we will collaborate with other groups at INM and the producer of the instru-

ment to analyze technologically rel-evant nanoparticles.

Synchrotron beam time was granted not only for the analysis of supraparticles, but also for research in the DFG-funded project “Mobility and interaction in na-noparticle self-assembly”. In 2011, Philip Born will perform his final experiments at the DESY in Hamburg to complement real-space electron microscopy results on particle superstructures with in situ small-angle x-ray scattering.

In general, the group will continue to analyze fundamental aspects of parti-cle arrangement, but with an increas-ing weight on interacting functional nanoparticles. We will continue and extend the collaboration with indus-try-oriented groups and explore the application of our results to the fabri-cation of new materials.

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systeme unterschiedlichste Aspekte biologischer Regulati onsmechanismen und wie sich daraus neue Konzepte für neue Materialien ableiten lassen.

Im Jahr 2010 standen folgende Arbei-ten im Mitt elpunkt:

• Pfauen-Feder und F-Kerati n: Wir untersuchten den Aufb au des Kieles von Pfauenfedern, etwa die Kerati n-struktur, und analysierten seine me-chanischen Eigenschaft en.

• Mechanotransdukti on: Gecko-inspi-rierte Haft materialien sind von gro-ßem Interesse für biomedizinische Anwendungen. In Zusammenarbeit mit dem Programmbereich Funkti o-nelle Oberfl ächen untersuchten wir, wie derarti ge Oberfl ächen die Zellent-wicklung des Modellorganismus Dic-tyostelium discoideum beeinfl ussen.

• Biomineralisati on in Pfl anzen und Perlmutt : In diesem Bereich liegt der Hauptschwerpunkt unserer Arbei-ten. Mit Hilfe der LC-PolScope-Tech-nologie konnten wir beispielsweise neue Erkenntnisse über die Struktur von Perlmutt und über Pfl anzenge-webe gewinnen.

Der Programmbereich Biomineralisa-ti on untersucht biologische Materiali-en sowie technische Materialien, die im Zusammenhang mit biologischen Grenzfl ächen in lebenden Organis-men stehen. Interessant ist diese For-schung vor allem aus zwei Gründen: Zum einen lassen sich damit neue Materialien generieren, die verbes-serte Eigenschaft en in Bezug auf die Gewebeverträglichkeit und nachhalti -ge Funkti onalität im Organismus auf-weisen. Andererseits fl ießen unsere grundlegenden Erkenntnisse in die Entwicklung biotechnologischer Ver-fahren ein. Diese Zielsetzung erfordert eine genaue Kenntnis grundlegender Mechanismen, sowohl was die Cha-rakterisierung komplexer natürlicher Komposit-Materialien anbetrifft , als auch wie die Natur diese komplexen Stoff e von der Nano-Skala bis hin zum makroskopischen Objekt syntheti siert und konstruiert. Aus diesem Grunde beschäft igen wir uns mit ausgewähl-ten Modellorganismen, von Einzellern und einfachen mehrzelligen Organis-men bis hin zu Pfl anzen und Tieren. Wir studieren anhand dieser Modell-

Biomineralisati on / Biomineralizati on

PD Dr. Ingrid M. Weiss

Das verbindende Element der Aufga-benstellungen im Programmbereich Biomineralisati on ist die Verbindung zum biologisch generierten Material, ebenso wie eine Inspirati on durch na-türliche und modifi zierte biologische Materialien für das Design technisch anwendbarer Werkstoff e. Wir wollen neue Sichtweisen und Erkenntnisse der Grundlagenforschung funkti onell in Form neuer Materialien, etwa für biomedizinische Anwendungen, um-setzen. Ein weiteres Ziel ist es, natür-liche Organismen für die Synthese bio-abbaubarer Rohstoff e unter dem Ge-sichtspunkt der Umweltverträglichkeit und Nachhalti gkeit nutzbar zu machen und mit vielfälti gen technologisch rele-vanten Funkti onen ausstatt en zu kön-nen. Unser Hauptanliegen, die neues-ten wissenschaft lichen Erkenntnisse aus der Biologie direkt in die Materi-alwissenschaft zu implementi eren, ge-lingt uns am INM aufgrund der engen Zusammenarbeit mit materialwissen-schaft lich ausgerichteten Programm-bereichen in besonderem Maße.

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to take advantage of the remarkable properties of natural materials with a hierarchical structure. This requires to first understand basic mechanisms that are involved in the formation of biological materials. One important aspect in this research area is to gain insight into the self-assembly mecha-nisms of biological macromolecules. There are several model organisms that we use for studying different as-pects in the field of new materials in-cluding:

• Peacock feathers and F-keratin: Me-chanics, hierarchy, and molecular as-pects of natural resources,

• Mechanotransduction: Cell response to gecko-inspired interface materi-als,

• Biomineralization in plants and na-cre: Optics and biotechnology.

Peacock Feathers: Mechanics of Hierarchical Materials

The feathers in the train of the peacock serve not for flying but for sexual dis-play. In quill embroidery, leather goods are beautified with patterns stitched with stripes of the cortex of peacock feathers. We studied the mechanical properties of the tail cover feathers of the peacock using analytical tools com-monly used for engineering materials. This type of study provides insight into the optimization processes during evo-lution. The feather rachis is a long, slen-der beam loaded in bending by its own weight. It consists of an outer circular conical shell, the cortex. The outer di-ameter and thickness of the cortex de-crease linearly from the body toward the tip. As demonstrated in our recent studies (J.Exp.Zool 2010,313A:690-703 [Cover of issue]; Adv.Eng.Mat. 2010,12:412-416), the selfsimilar ge-ometry leads to a distribution of la-bor. The cortex (longitudinal Young’s

Overview

The Program Division Biomineraliza-tion investigates biological materials, as well as man-made materials with a strong focus on the interface between the material and living tissue. This top-ic is of relevance for two main reasons: The first is to develop new materials with improved performance at the in-terface between synthetic materials and living tissues (e.g. implant materi-als for surgery). The second is to de-velop new biotechnological techniques

Figure 2: Environmental scanning electron microscopy (ESEM) images of various developmental patterns of D. discoideum cultivated on PDMS with the aspect ratio 1.7 (a,b) and the aspect ratio 3 (c,d). Note that cells are also located between the pillars (arrows).

Figure 1: Mechanical analysis of peacock feather rachis, a self-similar conical composite material (scheme, top). Bottom: Force–displacement curves of the cortex (fine line), the medulla (medium line), and the complete rachis (heavy line) superimposed. It is obvious that the whole (the rachis) is more resistant than the sum of its parts, cortex plus medulla. This is due to interfacial strengthen-ing effects.

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Biomineralizati on in Nacre and Plants: Opti cs and Biotechnology

The main focus of our acti viti es in the Program Division Biomineralizati on is to examine the interface between ar-ti fi cial materials and living ti ssue. An important model in this respect is the formati on of mollusk shells. There is litt le knowledge regarding mechani-cal feedback mechanisms within cells that encourage them to form new materials. A schemati c model (Fig. 3) has been developed, which inspires several current projects in our Pro-

modulus 3.3 GPa, transverse modulus 1 GPa) provides 96% of the longitudi-nal strength and bending rigidity of the feather. The medulla, a closed foam of 7.6% relati ve density, consists also of feather kerati n (Young’s modulus 10MPa) and provides 96% of the trans-verse compressive rigidity. Fracture stress of the cortex, both longitudinal and transverse, is 120MPa. In collabo-rati on with the University of Vienna, Austria, we studied the kerati n struc-ture in the cortex of peacocks’ feathers by X-ray diff racti on and found consid-erable diff erences along the feather, from the calamus to the ti p (J.Struct.Biol. 2010,172:270-275). Current investi -gati ons are underway in order to iden-ti fy molecular parameters consistent with our structural data.

Mechanotransducti on: Cell Response to Gecko-Inspired Interface Materials

For studying cellular eff ects at the in-terface of various materials, we use the model organism Dictyostelium discoi-deum. Within a joint project between INM Program Divisions Biomineraliza-ti on and Functi onal Surfaces, we stud-ied gecko inspired adhesives, which are att racti ve functi onal surfaces for many reasons. The polymeric materials con-tain microscale pillars that exhibit van der Waals interacti ons with other sur-faces, which can be fi ne-tuned in or-der to make adhesion reversible. The potenti al for switchability make gecko adhesives interesti ng for various bio-medical applicati ons. We can now use the model organism Dictyostelium dis-coideum to investi gate the formati on of biofi lms on such surfaces and how the surfaces aff ect cell development. As shown in Figure 2, micropatt erned surfaces can be used as a biophysical tool to interfere with multi cellular ti s-sue formati on in multi ple ways (Adv.Eng.Mat. 2010,12:405-411).

Figure 3: Top: Working hypothesis for understanding the relati onship between materials such as nacre and the response of ti ssues during the formati on process. The LC-PolScope image (bott om) represents a thin secti on at the interface between the nacre and prismati c shell part of Halioti s.

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Outlook

The common theme among the differ-ent research areas within the Program Division Biomineralization is the close relationship to and inspiration from biological materials. In addition to pro-viding new routes towards functional biomedical materials, the biotechno-logical branch of our research will cov-er sustainable aspects in our need for biodegradable materials with multiple and technologically relevant functions. Our main efforts towards implement-ing advanced aspects in materials sci-ence therefore include generation of basic knowledge of biological macro-molecules from the nano- to the mac-roscopic performance. To provide this knowledge in a suitable and adaptive manner for the needs of our today’s society, the development of the re-quired approaches and experimental techniques is underway.

gram Division at INM (ChemBioChem 2010,11:297-300). The investigation of the putative fundamental mechanisms underlying such a model requires the combination of interdisciplinary tech-niques, spanning the field from bio-chemistry and molecular biology to high-resolution structural biology. In order to investigate biological materi-als, particularly the interface between the material and the living tissue, we use LC-PolScope technology, which helped us to identify new details of shell structure at the nacre-prismatic interface (Fortschritte in der Metallog-raphie 2010, 42; Frankfurt, Germany). This technique turned out especially useful to gain new insights into plant tissues (Protoplasma 2010,246:49-64). Experiments are under way to identify a number of relevant parameters that currently prevent routine application in the field of complex biological mate-rials and living tissues.

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bieten. Verschiedene Abscheidungs-verfahren einschließlich thermisch un-terstützter CVD, plasma gestützter CVD (PECVD), laser gestützter CVD (LCVD) und Radiofrequenz-Sputt ern wurden eingesetzt, um funkti onelle Oberfl ä-chen herzustellen. Neben biologischen und medizinischen Anwendungen sind unsere nanostrukturierten und porösen Dünnschichten von Interesse für Kataly-se, kontrollierte Benetzung und Ener-giespeicheranwendungen. Die Haupt-themen des Programmbereichs sind:

• Verbesserte Osseointegrati on an na-nostrukturiertes Aluminiumoxid

• Mechanik der Zelladhäsion an nano-strukturierten Oberfl ächen

• Neuronenstrukturierung auf hierar-chisch strukturierten Oberfl ächen

• Oberfl ächenmodifi kati on für kardio-vaskuläre Implantante

Im Programmbereich CVD/Biooberfl ä-chen werden hauptsächlich Bott om-up-Synthesen von Nanomaterialien und ihre Anwendungen in Biologie und Me-dizin untersucht. Im Jahr 2010 arbeitete die Gruppe intensiv an der Entwicklung von Mikro- und Nanotopographien und erforschte ihre Wirkung auf die Adhäsi-on und Proliferati on von Zellen. In Zu-sammenarbeit mit Universitätskliniken und biomedizinischen Insti tuten wur-den der Einfl uss von mikrostrukturellen Parametern wie Oberfl ächenform und -geometrie, sowie der Oberfl ächen-eigenschaft en auf Zell-Oberfl ächen-Wechselwirkungen untersucht. Ein Schlüsselthema war die Möglichkeit, die Oberfl ächenchemie bei veränder-ter Oberfl ächentopographie beizube-halten. Im Programmbereich wurden molekulare Präkursoren syntheti siert, die besonders für Gasphasenabschei-dungsverfahren innovati ve Lösungen

CVD/Biooberfl ächen / CVD/Biosurfaces

Dr. Cenk Aktas

Der Programmbereich CVD/Bioober-fl ächen beabsichti gt die Intensivierung der Forschungsakti vitäten zur Wech-selwirkung von Zellen und Oberfl ä-chen. Hierbei wird besonders die Mo-difi kati on von Oberfl ächen dentaler, kardiologischer, orthopädischer und neurologischer Implantate erforscht. Nach den ersten erfolgreichen in-vitro-Experimenten sind für das Jahr 2011 in-vivo-Experimente (verschiede-ne Tiermodelle) geplant, da angenom-men wird, dass diese ti efere Erkennt-nisse über Wechselwirkung von Zellen und Oberfl ächen liefern werden. In diesem Zusammenhang soll in diesem Jahr die Zusammenarbeit mit dem In-sti tut für Experimentelle Chirurgie des Universitätsklinikums des Saarlandes weiter ausgebaut werden.

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fibrous encapsulation often accom-panied by a liquid-filled cavity. In the long term, this results in a loosening of the implant. It was tried to solve this problem by suppressing the growth of fibroblasts on the implant surface while improving the osteoblast adhe-sion. Previously, it was shown that fi-broblast cells show different adhesion and growth responses to topographi-cal changes with identical surface chemistry (pending patent) (Veith et al., Biofabrication 2 (2010) 035001-1 - 035001-10). This finding motivated the Program Division to investigate the topography-cell interaction on the molecular level. In 2010, in col-laboration with Saarland University Hospital (Prof. Pohlemann) and AO Foundation (Davos, Switzerland) it was shown in the case of osteoblast cells nanostructured topography triggers the up-regulation of growth factors (Figure 1) whereas no up-regulation was observed for fibroblast cells. This result takes us closer to the answer of the main question whether the topog-raphy can lead to a selective cell adhe-sion and proliferation independent of surface chemistry.

Mechanics of cell adhesion on nanostructured surfaces

Systematic investigations of the me-chanics of cell adhesion on nano-structured surfaces using a novel cell monolayer rheology (CMR) technique were performed in collaboration with Prof. Ott (Saarland University) (New J. Phys. 9 (2007) 419). Using this method, a broad range of cell responses can be analyzed. In Figure 2 it can be seen that fibronectin and Al/Al2O3 nanowire (NW) coatings exhibit similar rheologi-cal behavior in terms of amplitude and frequency sweeps. This indicates a similar structure of the cell cytoskel-eton, which is strongly governed by cell adhesion properties. It was shown

Introduction

Following the re-structuring of the for-mer departments CVD/PVD Technolo-gies and Life Science/Biomimetics into the new Program Division CVD/Bio-surfaces in 2009, bottom-up synthesis of nanomaterials and their functional applications in biology and medicine became the main research field of the Program Division. In 2010, intense re-search on the development of micro- and nanotopographies and their effect on the adhesion and proliferation of cells was carried out. In collaboration with university hospitals and other biomedical institutes, the influence of microstructural surface features on the cell-surface interaction was in-vestigated. A key issue was the ability to keep the chemical state identical at different scales and topographies. The Program Division synthesized mo-lecular precursors which provided in-novative solutions especially for gas phase deposition methods. Various deposition methods including thermal assisted CVD, plasma enhanced CVD (PECVD), laser assisted CVD (LCVD) and radio frequency (RF) sputtering were employed to fabricate functional sur-faces. Beside the biological and medi-cal applications, the nanostructured and porous layers are of interest for catalysis, controlled wetting and en-ergy storage applications.

Improved osseointegration on nanostructured alumina

Engineering ceramics such as alumina used in the treatment of hand and elbow fractures and in anthroplasty have long proven their biocompatibil-ity. On the other hand, such ceramics often failed clinically due to the lack of direct bonding to the bone, known as insufficient osseointegration. Further-more poor adherence of osteoblasts to the implant surface may lead to a

Figure 1: Up-regulation of osteoclacin (OC) de-pending on the nanowire density (LD, MD, HD, UHD).

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ence patt erning of NWs is a promising technique to enhance the guidance of neurons. This could be used to improve the performance of a neural prostheti c device aft er implanti ng the device in a non-invasive manner. Currently, the Program Division works on patt erning larger surfaces to observe the guid-ance of neurons on macro-scale which can lead to direct applicati ons in neu-ro-implants.

Surface modifi cati on for cardiovascular implants

Stents with various geometries fab-ricated from metals and alloys are commercially available but hand stent restenosis is sti ll a serious problem. Restenosis is mostly determined by whether the fi rst layer of cells are en-dothelial cells (ECs) or smooth cells (SMCs). Therefore, the stent surface plays a criti cal role in the preventi on of restenosis. In collaborati on with LATARUM at Kocaelli University, Tir-key, using femtosecond and nano-second laser treatments, the division developed nanostructured metallic surfaces which exhibit controlled wet-ti ng (Figure 4a and 4b). By the use of ultra short laser pulses we were able to structure the metallic substrates with-out altering the bulk properti es. Such surfaces examined with regard to their biocompati bility in collaborati on with Saarland University Hospital (Prof. Abdul-Khaliq). In additi on to metallic surfaces nanopatt ering of polymers such as PEEK by plasma treatment was demonstrated (Figure 5). Currently, the eff ect of an oxygen plasma treatment of PEEK on the adhesion and functi on-ality of ECs and SMCs is studied.

Also the collaborati on with interna-ti onal partners was extended. A joint project applicati on“Nano4Stent” with the Saarland University Hospital, the Korean University of Technology and

that the adhesion of fi broblasts on Al/Al2O3 NWs is comparable to that on fi bronecti n coated surfaces. To our knowledge, this is one of the strongest cell adhesions on inorganic surface re-ported so far.. This observati on shows that topography plays a crucial role in cell-surface interacti on. Further stud-ies will be directed towards the under-standing of the mechanisms of interac-ti on of cells with nanostructured sur-faces. Diff erences that occurred in the dynamics of cellular re-binding, when compared to fi bronecti n, will be inves-ti gated in detail. In additi on, diff erent cell types will be considered.

Neuron guidance on hierarchically structured surfaces

Interfacing well aligned nerve cells with microelectrodes is important for the successful performance of neural prostheti c devices. In additi on, neuron guidance is one of the challenging top-ics for the accurate rewiring of dam-aged neurons (Veith et al., Ceramic Transacti ons 214 (2010) 117-121). In this context, a new approach was de-veloped in collaborati on with the Life Science Department of the Univer-sity of Applied Science Kaiserslautern (Prof. Schäfer) to control the neuron guidance by hierarchical patt erning of surfaces. Firstly, substrates were coated with Al/Al2O3 NWs followed by a patt erning of the deposited coat-ings with the two-beam-interference method. Interference irradiati on of deposited NWs by nanosecond la-ser pulses in air leads to local melti ng and oxidati on of the Al-core to Al2O3. and to regularly arranged linear mi-crostructures which are composed of nanostructures (Figure 3a). Figure 3b shows a neuron cultured on patt erned NWs, whose neurites grew out from the cell body parallel to the grooves formed by laser interference. Our ex-periments indicate that laser interfer-

Figure 2: (a) Normalized viscoelasti c moduli derived by an amplitude sweep at f = 1 Hz for fi bronecti n and NWs coated glass plates. (b) Frequency-dependence of the normalized mod-uli determined by a frequency sweep with oscil-lati on amplitude of 1%.

Figure 3: (a) SEM image of laser patt erned na-nowires. (b) Alignment of neurons with laser patt erned nanowires.

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as the central method, new process will be developed which can combine INM’s wet chemistry background with gas phase approaches. One of the cur-rent themes is the development of a hybrid deposition system which basi-cally combines the pulsed laser depo-sition (PLD) and CVD methods within the same set-up. In case of the PLD process, we aim at the use of targets which can be synthesized within INM by incorporating nanoparticles in vari-ous matrices. A similar approach which combines reactive sputtering with PECVD will be also used. This will lead to the co-deposition of organic and inorganic materials for optimized sur-faces for biomedical applications.

In addition to new synthesis routes, we plan to pay special attention to the analysis of mechanical properties of nanostructured surfaces such as hardness and elasticity which are criti-cal issues for cell-surface interactions. Since the group finalized some of the in-vitro studies successfully, in-vivo studies (using various animal models) are planned. It is believed that in-vivo studies will give more insights about surface-cell interactions. In this con-text collaborations with experimental surgery departments will be strength-ened in the following year.

the Kocaeli University was granted by KORANET (Korean scientific coop-eration network with the European Research Area) within the 7th EU Re-search Framework. The project aims at the optimization of stent surfaces by laser assisted patterning and PECVD for preventing the stent restenosis. In addition, the project application “HeartSen” together with the Saarland University Hospital, LATARUM and the Madras Institute of Technology is one of 13 projects granted by New Indigo Program within the 7th EU Research Framework. The main aim of this pro-ject is to overcome the thrombosis formation on artificial heart valves by PECVD of Diamond Like Carbon (DLC) thin films.

Outlook

The Program Division CVD/Biosurfaces aims at intensifying research activi-ties on surface-cell interactions. Main emphasis will be given to the surface modification of dental, cardiologi-cal, orthopedic and neural implants. In this context, the Program Division plans to develop new strategies to fabricate various topographies with defined chemistry. Although the gas phase deposition methods will stay

Figure 4: (a) Stainless Steel treated with fem-tosecond laser (hydrophobic behavior) (b) Stainless Steel treated with femtosecond laser (super hydrophobic behavior).

Figure 5: SEM image of PEEK treated with Plasma.

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Im Rahmen bisheriger Untersuchungen wurde festgestellt, dass

• 30-130 nm große Silika-Parti kel in Lungen- und Darmepithelzellen auf-genommen werden (Schübbe et al., 2010). 80 nm große Silika-Nanop-arti kel werden über einen akti ven Prozess aufgenommen, der anschei-nend weder über Clathrin noch Ca-veolin-vermitt elte Endozytose ver-mitt elt wird.

• Kleinere Parti kel mit Größen von 30 nm gelangen schließlich in den Zellkern, während größere Parti kel (>80 nm) aus diesem ausgeschlossen bleiben (Schübbe et al., in Vorberei-tung)

• Untersuchungen zur Toxizität von Sil-ber-Nanoparti keln zeigen, dass diese Parti kel bis zu einer Konzentrati on von 200 µM Ag0 keinen signifi kanten Eff ekt auf die Stoff wechselakti vität der Zellen und ihre Morphologie ha-ben. Im Gegensatz dazu wirkt AgNO3 bereits bei deutlich geringerer Kon-zentrati on toxisch. Analysen mit ei-ner silberionenselekti ven Elektrode zeigen, dass für diesen Eff ekt eine Freisetzung von Silberionen verant-wortlich ist (Koch et al., in Vorberei-tung). Geplant ist, die Wirkung der

Ziel der Juniorforschungsgruppe Nano Zell Interakti onen ist es, den Einfl uss gezielt hergestellter Nanomaterialien, insbesondere von Nanoparti keln aus anorganischen Materialien, auf Zellen menschlicher Herkunft festzustellen. Vor allem durch den Einsatz mikroskopi-scher Methoden werden die Wechsel-wirkungen der Nanoparti kel mit Struk-turen wie Zellorganellen und anderen biologischen Komponenten bis ins Detail beschrieben. Ergänzend durch-geführte Analysen der Auswirkungen der Nanoparti kel auf die Biochemie der Zellen ermöglichen es, die Anwesenheit der Parti kel sowie ihren Status innerhalb der Zelle und die Zellantwort miteinan-der, aber auch mit den tatsächlichen Ei-genschaft en der eingesetzten Parti kel, zu verknüpfen. Um Mechanismen auf-zuklären, die möglicherweise dazu füh-ren, dass Nanoparti kel toxisch wirken, liegt unser Interesse darin festzustellen, ob und inwiefern die Eigenschaft en der Nanoparti kel unter relevanten experi-mentellen Bedingungen verändert wer-den, beispielsweise durch Wechselwir-kungen mit Bestandteilen der Kultur-medien. Weiterhin untersuchen wir die Aufnahme und Lokalisati on der Parti kel in besti mmten Regionen der Zellen, ihre Agglomerati on sowie ihren intrazellulä-ren Transport. Eine unserer besonde-ren Methoden ist die STED (Sti mulated Emission Depleti on)-Mikroskopie. Sie ermöglicht uns, den Status der Nano-parti kel, beispielsweise ihre Agglome-rati on, sowie Veränderungen zellulärer Strukturen detailgenau festzustellen. Um die Nanoparti kel in zellulärer Um-gebung sowie im lebenden System de-tekti eren zu können, verwenden wir fl uoreszenzmarkierte Modellparti kel defi nierter Größe und Oberfl äche, die wir spezifi sch für unsere Untersuchun-gen herstellen. Unser Ansatz zeichnet sich dadurch aus, dass wir biologische, chemische und physikalische Kenntnis-se und Methoden eng miteinander ver-knüpfen.

Nano Zell Interakti onen / Nano Cell Interacti ons

Dr. Annett e Kraegeloh

Nanoparti kel mit der Freisetzung von Ionen sowie mit deren intrazel-lulärer Konzentrati on zu korrelieren. Die Untersuchungen zur Silber-Toxi-zität erfolgen in enger Zusammenar-beit mit der Physikalischen und Che-mischen Analyti k.

Die Gruppe Nano Zell Interakti onen kooperiert im Rahmen eines vom saar-ländischen Ministerium für Wirtschaft und Wissenschaft geförderten Projek-tes zum intrazellulären Transport von Nanoparti keln mit den Arbeitsgruppen Pharmazeuti sche Biologie, Theoreti -sche Physik sowie Mathemati k und Informati k der Universität des Saarlan-des (UdS). In einem 2010 vom BMBF bewilligten Vorhaben im Rahmen der Ausschreibung NanoCare untersucht die Gruppe gemeinsam mit Partnern der Universität Mainz, der UdS, und den Firmen Sarastro und Nanogate systemati sch die Auswirkungen nano-skaliger Kontrastmitt el auf die Gesund-heit des Menschen.

Die Gruppe Nano Zell Interakti onen wird ab dem 1. Januar 2011 zu einem vollen Programmbereich erweitert.

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induce toxic effects on the cells, we aim to analyze if and how the nanoparticles are influenced under experimental con-ditions, for example by chemical reac-tions with constituents of the medium. Furthermore, we investigate the uptake and localization of particles in distinct subcellular regions, their agglomeration as well as their cellular transport. One of the distinctive methods we used is the STED (Stimulated Emission Depletion) microscopy. STED allows us to detect the nanoparticle state, for example their ag-glomeration, but also alterations of cel-lular structures in detail. For our experi-ments we apply fluorescently labeled model particles, with defined size and surface properties, specifically produced for this purpose. Our approach is distin-guished from others by a tight combina-tion of biological, chemical, and physical knowledge and methods.

Uptake and Localization of Silica Nanoparticles

After it has been shown that silica par-ticles up to 130 nm in size are internal-ized by human lung and colon epithelial cells (Schübbe et al., Adv. Eng. Mater. 2010, 12, (5), 417-422), during 2010 fluorescently labeled silica-particles of various sizes (30 nm and 80 nm) have been used to further analyze the up-take process and cellular localization. We observed that 80 nm particles were taken up by an active process. After up-take, the particles reside in membrane bound vesicles as has been shown using a variant of green fluorescent protein to label cellular membranes. Whereas the smaller particles are transported into the nucleus, the bigger particles are excluded from that compartment (Schübbe et al., in preparation). As has previously been shown for other parti-cle sizes, the particles tend to agglom-erate after uptake into the cells. Particle agglomerates were also detected inside the nucleus (Figure 2).

Introduction

The aim of the Junior Research Group Nano Cell Interactions is the determina-tion of the effects of engineered nano-materials, in particular inorganic nano-particles, on cells of human origin. The interactions of nanoparticles with struc-tures like cellular organelles and other biological components can be observed in detail, most notably by use of micro-scopic techniques (Figure 1). Additional analyses of nanoparticle impact on the cellular biochemistry allow to correlate the presence of particles as well as their status with the cellular response and the actual particle characteristics. To elucidate mechanisms that potentially

Figure 1: A confocal microscopy image of A549 lung epithelial cells after incubation in presence of nanoparticles (red). Filaments of the actin cytoskeleton are labeled green, further cellular struc-tures and nuclei are visualized by differential interference contrast.

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of health impacts of nanoscale con-trast agents. NanoKon is funded by the Federal Ministry of Educati on and Research within the topic NanoCare: eff ects of syntheti c nanomaterials on human health. As a fi rst step within this project, commercial iron oxide nanoparti cles are used as a reference material for biological experiments. The role of the Junior Research Group Nano Cell Interacti ons is to analyze the parti cle characteristi cs under experi-mental relevant conditi ons and to fl uo-rescently label the parti cles. We will also look at the uptake of parti cles into epithelial cells of the gastrointesti nal tract (enterocytes) with microscopi-cal analysis, focusing on cellular orga-nelles like mitochondria.

The Junior Research Group Nano Cell Interacti ons will be promoted to full Program Division status on January 1, 2011.

Eff ects of Silver Nanoparti cles

Investi gati ons of the toxicity of silver nanoparti cles on cells indicate that these parti cles do not exert a signifi -cant eff ect on the metabolic acti v-ity and morphology of A549 cells in a wide concentrati on range (up to 200 µM Ag0) (Figure 3). In contrast, AgNO3 reduced the cell acti vity and aff ected cell morphology at lower con-centrati ons. Analyses using a silver ion selecti ve electrode indicate that the release of silver ions from the parti cles is one of the main causes of nanosilver toxicity (Koch et al., submitt ed). Fur-ther studies will help to elucidate the mechanism by which these parti cles are internalized and what there target structures within the cell are. We fur-ther plan to correlate the eff ect of the nanoparti cles with the release of ions as well as with the cellular ion release. The investi gati ons of silver toxicity on individual cells are performed in coop-erati on with the Service Groups Physi-cal Analysis and Chemical Analysis.

Cooperati on and Outlook

The Junior Research Group Nano Cell Interacti ons is collaborati ng with the Pharmaceuti cal Biology, Theoreti cal Physics and Mathemati cs and Com-puter Science groups from Saarland University in the frame of a project investi gati ng intracellular transport of gold nanoparti cles funded by Saarland Ministry for Economics and Science. In 2010, the project NanoKon started. It focuses on the systemati c evaluati on

Figure 3: Epithelial cells previously incubated in presence of silver nanoparti cles a) light microscopi-cal image of living A549 cells, b) scanning electron micrograph of A549 cells, c) confocal image of Caco-2 cells, acti n cytoskeleton (green), silver nanoparti cles (red).

Figure 2: Model for the pathway of silica na-noparti cles uptake into the nucleus of human cells. Aft er uptake by endocytosis into mem-brane bound vesicles (red circles), the parti cles (red spheres) are released into the cytosol. Aft er binding of nuclear proteins (green circles) they are transported into the nucleus through nuclear pores (arrows). Bigger parti cles with a diameter of more than 80 nm do not enter the nucleus.

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einer nachgiebigen, sphärischen Ober-fläche mit Härchen wurden entwickelt. Diese Modelle erlauben die Simulation von Experimenten, in denen die Ab-zugskräfte zwischen solchen Oberflä-chen gemessen werden. Die Ergebnisse der Simulationen lassen auch den Test von Hypothesen zu, die die Natur der Adhäsion zwischen den Härchen auf der sphärischen Oberfläche und dem flachen Objekt betreffen. Simulationen der Adhäsion zwischen einer nachgie-bigen Oberfläche mit Vertiefungen mit einer flachen und steifen Oberfläche zeigten eine bistabile Adhäsion. Eine schwache Adhäsion kann durch druck-loses Zusammenfügen der beiden Oberflächen erreicht werden, und die Oberflächen können wieder vollstän-dig voneinander getrennt werden. Die schwache Adhäsion kann durch Druck in eine starke Adhäsion umgewandelt werden. Die Oberflächen sind dann nicht mehr einfach zu trennen. Zu die-sem bistabilen Adhäsionskonzept wur-de ein Patent angemeldet.

Zellmechanik: Ein Modell für die Kon-traktierbarkeit, das Remodelling des Zytoskeletts und die Adhäsion in bio-logischen Zellen wurde entwickelt. Dieses Modell erlaubt es, diverse ex-perimentelle Beobachtungen wie zum Beispiel den Zusammenhang der kon-traktilen Kräfte mit der Steifheit der Zellumgebung und der Orientierung der zytoskeletalen Stressfasern wäh-rend einer zyklischen Anspannung der Zelle zu simulieren. Das Modell wird erweitert, um auch die Nutzung in Si-mulationen der Partikeltoxikologie zu ermöglichen, in denen Endozytose zur Aufnahme der Partikel führt und die Umbildung des Zytoskeletts stimuliert wird. Des Weiteren wurde damit be-gonnen, das Zellmodell in Richtung auf die Biomineralisation auszuweiten.

Nanopartikel-Neuron-Interaktionen (in Kooperation mit dem Programmbe-reich Nano Zell Interaktionen): Elekt-

Neben dem kommissarischen Leiter, Prof. Dr. Robert McMeeking (Universi-ty of California, Santa Barbara, UCSB), ist Prof. Dr. Dr. Daniel Strauss im Pro-grammbereich tätig. Der Programmbe-reich befindet sich noch im Aufbau.

Im Jahr 2010 wurde eine Reihe von For-schungsprojekten mit Bezug zu aktuellen INM-Forschungsthemen durchgeführt:

Schaltbare ferroelektrische Speicherele-mente: Ein Projekt in Kooperation mit dem Programmbereich Nanoprotect hat die Modellierung des ferroelektri-schen Schaltverhaltens von polymer-matrixgebundenen Partikeln zum Ziel. Dieses Kompositsystem wurde als Spei-chermedium entwickelt, bei dem Daten in Form von Bits gespeichert werden, die durch Regionen repräsentiert wer-den, deren Polarisation umgeschaltet wird. Aufgrund des Unterschiedes zwi-schen den dielektrischen Eigenschaften der ferroelektrischen Partikel und der Polymermatrix unterscheidet sich das elektrische Feld in den Partikeln we-gen der Depolarisation vom angelegten elektrischen Feld. Das Depolarisations-feld kann als Funktion des Unterschie-des der dielektrischen Eigenschaften, der Größe des ferroelektrischen Schalt-verhaltens in den Partikeln und des an-gelegten elektrischen Feldes, auf Basis der Potentialtheorie simuliert werden. Aufgrund von Näherungen wird eine mittlere Feldtheorie als Basis für das Modell der Depolarisation erhalten. Die Ergebnisse für das Depolarisationsfeld erlauben eine genauere Voraussage des elektrischen Feldes in den Partikeln. In der Konsequenz können das angelegte elektrische Feld, bei dem der Schaltvor-gang beginnt, sein Umkehrpunkt sowie die effektive Dielektrizitätskonstante des Komposites genauer modelliert werden. Die Ergebnisse tragen zu einem besseren Design des Kompositspeicher-mediums bei.

Adhäsion (in Kooperation mit dem Pro-grammbereich Funktionelle Oberflä-chen): Modelle der Adhäsion zwischen einer steifen, glatten Oberfläche und

Modellierung/Simulation / Modelling/Simulation

Prof. Dr. Robert McMeeking

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rophysiologische Messungen wurden durchgeführt, die Aufschlüsse über die Interakti onen von Nanoparti keln (NP) mit neuronalen Zellen auf der Mikro-skala liefern. Nach Zugabe der NP konn-ten signifi kante Unterschiede in den gemessenen Ionenströmen beobachtet werden. Um die zugrundeliegenden Mechanismen zu untersuchen, wurde ein computerbasiertes Modell entwi-ckelt, das bekannte mathemati sche Beschreibungen solcher Ionenströme an die Messdaten fi tt et. Es konnten so Ursachen für das veränderte Verhal-ten dieser Zellen evaluiert werden. Das Modell erlaubt erste Einblicke in die zugrundeliegenden Mechanismen der Nano-Zell-Interakti on und dient als Mo-dul in einer Multi skalenarchitektur, die sich mit makroskopischen Auswirkun-gen von NP im Organismus auseinan-dersetzt. Dazu wurden die Ergebnisse in ein weiteres System integriert, wel-ches mögliche Auswirkungen von NP auf die Dynamik neuronaler Netzwerke modelliert. Die Simulati onsergebnisse legen nahe, dass NP in hirnorganischen Strukturen wichti ge Prozesse beeinfl us-sen. Solche Modelle liefern Beispiele, wie Eff ekte auf einer kleinen Skala zu mehr makroskopischen Eff ekten inte-griert werden können. Diese Erkennt-nisse sind sehr wichti g um Risiken und mögliche Vorteile von NP-Expositi on in neuronalen Strukturen zu verstehen und sind so relevant für Fragen bezüg-lich der Nanotoxizität, mit welchen sich das INM eingehend beschäft igt.

Tribologische Modellierung (in Ko-operati on mit dem Programmbereich Nanotribologie): Bei diesem Projekt wurde eine ‚machine learning’-Archi-tektur zur Vorhersage von Reibungsko-effi zienten und der Verschleißrate bei tribologischen Messungen entwickelt.

Validiert wurde diese Architektur an-hand von Daten vorheriger tribolo-gischer Tests. Neben der Vorhersage von Messergebnissen werden Infor-mati onen über mechanische Material-eigenschaft en (microhardness, impact strength, Young‘s modulus etc) von Kompositmaterialien gewonnen. Diese Eigenschaft en werden dann dazu be-nutzt, das tribologische Verhalten ver-schiedener Komposite vorauszusagen und opti male Kompositzusammenset-zungen zu identi fi zieren. Idealerweise erlauben diese Informati onen dem INM, einen Tribo-Werkstoff mit opti -malen Reibungs- und Verschleißeigen-schaft en zu entwickeln. Ferner ist auch eine Sensivitätsanalyse implementi ert, anhand dieser die für das Modell am relevantesten mechanischen Materi-aleigenschaft en identi fi ziert werden sollen.

Folgende Themen werden aus heuti ger Sicht für die zukünft ige Entwicklung des Programmbereiches Modellierung / Simulati on von Interesse sein:

• Kontaktmechanik strukturierter Sys-teme mit weichen Oberfl ächen;

• Tribologie von Hybridschichtsyste-men;

• Benetzung und Kapillarität;• Opti mierung von mikroopti schen

Systemen;• Mikromechanik natürlicher und

künstlicher Kompositsysteme;• Simulati on von Wachstumsprozes-

sen;• Modellierung von Zelladhäsion und

zellbiologischer Prozesse, speziell in Wechselwirkung mit Substraten oder Nanoparti keln.

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Adhesion (collaboration with the Pro-gram Division Functional Surfaces): Models of adhesion between a stiff smooth surface and a compliant, fibril-lar spherical surface have been devel-oped. These models allow simulation of experiments carried out at INM and elsewhere in which the pull-off forces between such surfaces has been mea-sured. The results of the simulations allow hypothesis testing to be carried out regarding the nature of adhesion between the fibrils on the spherical surface and the flat object. For exam-ple, assessments can be made in re-gard to whether the pull-off condition for an individual fibril is deterministic, or if it obeys a probabilistic behavior in which the force at which separation occurs is controlled by defects in the surfaces that are adhering. In addition, simulations of the adhesion of a com-pliant dimpled surface with a flat, stiff one have been developed and show that bi-stable adhesion can be devel-oped. In this phenomenon, weak ad-hesion can be achieved by placing the surfaces together without compres-sion. In this state, the surfaces can be readily separated. The weak adhesion condition can be converted to strong adhesion by application of pressure to press the apices of the dimples against the flat surface. The surface now can-not be easily detached. A patent has been applied for regarding this bi-sta-ble adhesion concept.

Cell mechanics: A model for contractili-ty, cytoskeleton remodeling, and adhe-sion in biological cells has been devel-oped, coupled to signaling controlled by proteins generated in response to mechanical stimulations of the liga-ments to which the cell is attached. This model is able to simulate various experimental observations such as the scaling of contractile forces with the stiffness of the cell’s environment, and the orientation of cytoskeletal stress-fibres during cyclic straining of the cell.

In addition to Prof. Dr. Robert McMeek-ing, University of California, Santa Bar-bara (UCSB), who is acting as provisional head, this division is supported by Prof. Dr. Dr. Daniel Strauss. The Program Divi-sion is still under development.

Research Projects

In 2010, the Program Division pursued a small number of research projects relevant to topics currently of impor-tance within INM:

Switching in ferroelectric memory: A project is underway, in collaboration with the Program Division Nanopro-tect, that has the objective of model-ing ferroelectric switching of particles embedded in a polymer matrix. This composite system is designed to be a memory device, with data stored in the form of bits represented by regions that are switched between upward and downward polarization. Due to the contrast in dielectric properties be-tween the ferroelectric particles and the polymer matrix, the electric field in the particles differs from the applied electric field because of depolariza-tion. The depolarization field can be computed as a function of the contrast in dielectric properties, the extent of ferroelectric switching in the particles and the applied electric field, with po-tential theory used as the basis of the simulations. Approximations are made that lead to a mean field theory as the basis of the model for depolarization. The results for the depolarization field enable the more accurate prediction of the electric field in the particles. As a consequence, the applied electric field at which switching commences, at which it reverses and the effective dielectric permittivity of the compos-ite memory can be modeled more ac-curately. These results contribute to an improved ability to design the compos-ite ferroelectric memory.

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relevant to issues of nanotoxicology being considered at INM.

Tribological Modeling (collaborati on with the Program Division Nanotribol-ogy): A machine learning architecture for the predicti on of the fricti on coef-fi cient and wear rate for tribological measurements has been developed. This architecture has been validated with data from previous tribological tests. To augment measurement pre-dicti on, an extended model is uti lized in this scheme to obtain informa-ti on on mechanical material proper-ti es (microhardness, impact strength, Young’s modulus etc.) for diff erent compounds. Such mechanical proper-ti es will then be used to develop infor-mati on regarding the tribological per-formance of a variety of compounds to identi fy the appropriate mixture ingredients. Ideally, this will allow the design of tribological compounds hav-ing opti mal fricti on and wear proper-ti es. A sensiti vity analysis to identi fy the most relevant material mechanical properti es for the model will be imple-mented next.

Outlook

From today’s perspecti ve, the follow-ing topics are assessed to be of signifi -cance for future developments in mod-eling and simulati on:

• contact mechanics of structured sys-tems with soft surfaces;

• tribology of hybrid layered systems;• wetti ng and capillarity;• opti mizati on of micro-opti cal systems;

• micro mechanics of natural and arti -fi cial composite systems;

• simulati on of growth processes;• modeling of cell adhesion and of cell

biological processes, especially in interacti on with substrates or nano-parti cles.

The model is being extended to allow for its uti lizati on in parti cle toxicology simulati ons, where endocytosis ingests parti cles, and sti mulates remodeling of the cytoskeleton. Such models should be relevant to issues of nanotoxicol-ogy that are being considered at INM. In additi on, we plan to develop the cell model in the directi on of biominerali-zati on, another topic pursued at INM.

Nanoparti cle-Neuron-Interacti ons (col-laborati on with the Program Division Nano Cell Interacti ons): Electrophysi-ological measurements on single excit-able cells were carried out to investi -gate the interacti ons of nanoparti cles (NPs) with neuronal cells at the micro-scale: patch–clamp recordings were performed to evaluate the eff ects of coated silver nanoparti cles on the cell’s ionic currents compared to con-trols. Signifi cant diff erences were ob-served in the presence of NPs. To shed light on the underlying mechanisms, a computati onal model has been devel-oped that is fi tti ng well known math-emati cal descripti ons of ionic conduc-tances to the measured data. Based on this, reasons for the changed behavior of those cells were evaluated. This model provides insights on underlying mechanisms and serves as a module in a multi scale computati onal scheme that will give a percepti on of system-ati c characteristi cs of NP-human inter-acti ons. To this, the results were inte-grated into a computati onal system that models the possible eff ects of NPs on network dynamics. Our simulati on results suggest that NPs in neuronal circuits of the brain infl uence its func-ti on. Such models show how fi ndings in the small scale can be integrated to predict macro scale eff ects arising from the presence of NPs at diff erent sites in the mammalian nervous sys-tem. Such outcomes are important as an aide for understanding the risks and possible benefi ts of the exposure of neuronal structures to NPs and are

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Tribology – Correlation between Wear Characteristics and Material Properties of Polymers Ranged from Sub-Micro to Macro Scale (FUNDTRIBO)” begonnen, das von der European Science Foun-dation gefördert wird. Darin werden an Nanopartikel-verstärkten Polyethe-retherketon (PEEK) Kompositmateriali-en die Grundlagen der Tribologie und Effekte mit Bezug zu Abrasions- und Reibungsphänomenen auf großer, Ma-kro- und Nanoskala untersucht und verglichen. Die Forschungsaktivitäten im Programmbereich umfassen die Materialherstellung, die Risikoanaly-se, die Tests auf der Nanoskala, so-wie die Modellierung und Simulation des tribologischen Verhaltens auf den diversen Größenskalen unter Benut-zung eines künstlichen neuralen Netz-werks (ANN). Weiterhin wurde im Jahr 2010 eine Doktorarbeit auf dem Ge-biet der elektrochemischen Synthese von nanoskaligen Metalloxiden ab-geschlossen. Neben Untersuchungen am System Indium-Zinn-Oxid lag der Schwerpunkt der Arbeit auf dem Sys-tem Zinkoxid, das sowohl direkt unter Einstellung spezifischer Prozesspara-meter während der Synthese, als auch über den Umweg über Zwischenstufen verschiedener Hydroxid- und Schicht- hydroxidsysteme und deren thermi-scher Behandlung mit entsprechenden Eigenschaften erhalten werden konnte.

In den vergangenen Jahren wurden Umstrukturierungen vorgenommen, die zu einer deutlichen Verschlankung und finanziellen Entlastung geführt haben. Es ist vorgesehen, einen neu-en Leiter für den Programmbereich zu gewinnen, der verfahrenstechnische Kompetenz besitzt und das Anwen-dungszentrum zu neuen Themen führt.

Das Anwendungszentrum NMO (Neue Materialien für die Oberflächentech-nik) ist die Schnittstelle des INM für den Technologietransfer in die Indust-rie. Die Entwicklungsarbeiten sind mit dem Up-scaling chemischer Synthesen und der Optimierung von Applikations- und Verarbeitungstechnologien für die neu entwickelten Materialien des INM befasst. Zur technischen Ausstat-tung gehören Reaktionskalorimeter, Pilotanlagen zur Materialsynthese bis in den Technikumsmaßstab, automa-tische Anlagen zur Nassbeschichtung und für CVD-Prozesse sowie Anlagen zur Oberflächenvorbehandlungs- und Härtungstechnik. Im Berichtszeitraum wurde eine neue Lackierkabine mit integriertem Industrieroboter zur ma-schinengesteuerten Sprühbeschich-tung komplexer Probengeometrien aufgebaut und in Betrieb genommen. Sie hat eine Außenmaß-Größe von 4,5 m x 4,0 m x 3,6 m und verfügt über die Möglichkeit, per Erdgasheizer mit einer Leistung von 300 kW auf bis zu 90 °C aufzuheizen. Die Sprühkabine be-sitzt eine pneumatisch betriebene Auf-fahrrampe mit einer Hebekraft bis zu 2 t. Weiterhin ist sie mit einem Dreh-teller und einem 6-Achs-Knickarm-Sprühroboter ausgerüstet, die syn-chronisiert betrieben werden können. Der Sprühroboter kann über ein Schie-nensystem, das mit einer speziellen Abdichtung in die Sprühkabine verlegt wurde, wahlweise auch außerhalb ab-gestellt werden. Weiterhin wurde ein Großdispermat mit Edelstahldoppel-wandreaktoren und variabler Rürgeo-metrie angeschafft, der es ermöglicht, Lackansätze bis zu 50 l Reaktorvolu-men zu fahren.

Im Bereich Verfahrenstechnik wurde im Jahr 2010 das Projekt “Fundamentals of

Anwendungszentrum NMO/Verfahrenstechnik / Application Center NMO/Chemical Engineering

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In the area of process technology, a project on “Fundamentals of Tribology - Correlati on between Wear Characteris-ti cs and Material Properti es of Polymers ranged from Sub-micro to Macro-scale (FUNDTRIBO)” started in 2010. This pro-ject is funded by the European Science Foundati on. The scope of the project is set on nanoparti cle reinforced poly-etheretherketone (PEEK) composite materials in order to understand the fundamentals of tribology and the ef-fects in relati on to abrasion and fric-ti on phenomena on large-, macro- and nano-scale. The research acti viti es in the Program Division comprise the fab-ricati on of the composite materials, risk analysis, tests at the nano-scale, mod-elling and simulati on of the tribological behavior on the various length-scales combined with the arti fi cial neural net-work (ANN). Furthermore, a PhD thesis has been completed dealing with the electro-chemical synthesis of nano-scaled metal oxides. The investi gati ons focused on the systems indium-ti noxide and zinc oxide. The aim was the synthe-sis by variati on of process parameters, via hydroxide and layered hydroxide systems as intermediates and by ther-mal post-treatment.

In recent years, signifi cant re-organiza-ti on that led to lower cost was imple-mented. It is planned to install a new head of the Program Division with a strong process engineering compe-tence. This person will initi ate new topics in the Program Division.

The Applicati on Centre NMO (New Ma-terials for Surface Technology) is INM’s interface for technology transfer. The research and development acti viti es concentrate on chemical up-scaling of synthesis and opti mizati on of applica-ti on and processing technologies for newly developed materials. The tech-nical equipment comprises reacti on calorimeter, pilot faciliti es for material synthesis up to the technical level, au-tomati c equipment for wet-coati ng and chemical vapor depositi on technology as well as equipment for surface pre-treatment and curing techniques.

A new spraying chamber with an inte-grated roboti c system for automati c spray-coati ng applicati on has been built-up in 2010 and started opera-ti on already. The spraying chamber has a size of 4.5m x 4.0m x 3.6m and is equipped with a gas-heati ng system having a power of 300 kW to cure sam-ples up to 90°C. The chamber has a pneumati cally driven ramp which can be used to lift samples up to a weight up to 2 t. Furthermore, it comprises a rotati onal table and a spraying robot-ic system with six axes. The rotati ng table and the robot can be driven in synchronized operati on. The spraying robot can be placed either inside or outside the spraying chamber. As an extension for the chemical up-scaling an additi onal dispersing reactor made from stainless steel and with variable sti rring geometry has been set in oper-ati on. It can be used to perform techni-cal synthesis up to 50 l reactor volume.

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fentlichte Publikation unter Wahrung der urheberrechtlichen Bestimmungen elektronisch zweitveröffentlicht wird.

SciDok: Der Wissenschaftsserver der Saarländischen Universitäts- und Landesbibliothek

Technische Voraussetzung für die elek-tronische Zweitveröffentlichung ist eine Repository-Infrastruktur, die den Qualitätskriterien und Standards elek-tronischen Publizierens entspricht. Im Rahmen ihrer Kooperationen nutzt die INM-Bibliothek SciDok, den nach DINI zertifizierten Open-Access-Wis-senschaftsserver der Saarländischen Universitäts- und Landesbibliothek. Im Berichtszeitraum wurde innerhalb von SciDok ein INM-Portal für Open-Access-Publikationen aus dem INM er-stellt: http://scidok.sulb.uni-saarland.de/sulb/portal/inm. SciDok enthält mit Ende des Berichtsjahres über 1000 vor-wiegend ältere Dokumente von ehe-maligen und derzeitigen INM-Wissen-schaftlerinnen und Wissenschaftlern, für die der Bibliothek von den Autoren ein einfaches Nutzungsrecht übertra-gen wurde und deren Zweitveröffent-lichung den entsprechenden Verlags-regelungen laut Sherpa-Romeo-Liste entspricht: http://www.sherpa.ac.uk/romeo. Im Rahmen des Open-Access-Workshops der Saarländischen Univer-

Die Bibliothek des INM ist eine wis-senschaftliche Spezialbibliothek und erbringt Dienstleistungen in den Berei-chen Dokumentation, Recherche und Dokumentlieferung. Ein Schwerpunkt-thema der INM-Bibliothek im Berichts-jahr 2010 waren Aktivitäten zur Um-setzung des Open-Access Gedankens.

Open-Access: Freier Zugang zu wissenschaftlicher Information

Nach der „Berliner Erklärung über of-fenen Zugang zu wissenschaftlichem Wissen“ bezeichnet Open-Access den freien Zugang zu Wissen und Infor-mationen ohne finanzielle, technische oder rechtliche Barrieren. Der Begriff „Wissen“ umfasst dabei sowohl die eigentliche Forschungspublikation als auch weitere digitale Medien sowie Forschungsdaten. Der Begriff „Zu-gang“ meint die Erlaubnis, die Veröf-fentlichung für jeden verantwortlichen Zweck unter der Bedingung der Nen-nung der korrekten Urheberschaft zu kopieren, zu nutzen, zu verteilen oder zu übertragen. Grundsätzlich existie-ren zwei Strategien zur Umsetzung von Open-Access: Neben dem „Goldenen Weg“, dem Publizieren einer wissen-schaftlichen Arbeit in einer frei zugäng-lichen Zeitschrift, gibt es den „Grünen Weg“, bei dem eine bereits in einer traditionellen Verlagszeitschrift veröf-

Servicegruppe Bibliothek / Service Group LibraryElke Bubel

sitäts- und Landesbibliothek im Okto-ber 2010 wurden diese Aktivitäten von der INM-Bibliothek präsentiert.

AK Open-Access der Leibniz- Gemeinschaft

Mit der Verabschiedung der Open-Ac-cess-Leitlinie verfolgt auch die Leibniz-Gemeinschaft das Ziel, die freie Zugäng-lichkeit wissenschaftlicher Publikationen ihrer Einrichtungen zu fördern. Im Be-richtsjahr hat sich der Arbeitskreis Open-Access http://www.leibniz-gemein-schaft.de/?nid=akroa&nidap=&print=0 der Leibniz-Gemeinschaft neu konstitu-iert; die INM-Bibliothek ist in diesem Ar-beitskreis vertreten. Ziel der Leibniz-Ak-tivitäten ist der Aufbau eines Dokumen-tenservers, in dessen Infrastruktur alle Leibniz-Institute abgedeckt sein werden und der die Open-Access-Publikationen von Leibniz-Wissenschaftlerinnen und Wissenschaftlern sichtbar macht. Mit der Umsetzung wurde eine Arbeitsgrup-pe Open-Access der WGL unter Mitwir-kung der Saarländischen Universitäts- und Landesbibliothek betraut.

Künftige Schritte

Bei der Beteiligung des INM an den Open-Access-Aktivitäten der Leibniz-Gemeinschaft sind folgende Schritte geplant: Bei den bereits in SciDok frei zugänglichen INM-Publikationen wird überprüft werden, inwiefern sie den formalen und inhaltlichen Vorgaben der Leibniz-Gemeinschaft entsprechen. Publikationen, die den Leibniz-Kriterien entsprechen, werden dann auf den Do-kumentenserver der Leibniz-Gemein-schaft übertragen. Bei aktuellen Pub-likationen sollen künftig die urheber-rechtlichen Bestimmungen geprüft und im Falle des Einverständnisses der Au-toren die Preprint- bzw. Postprintver-sionen der Publikationen auf dem Do-kumentenserver der Leibniz-Gemein-schaft zugänglich gemacht werden.

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zunächst aus den biologischen Matri-ces separiert und nachfolgend in fl üch-ti ge Alditolderivate reduziert werden. Bild 1 zeigt die Gas-Chromatogramme von Alditol-Proben unterschiedlicher Konzentrati on, die mit GC/MS detek-ti ert werden konnten.

Zusammen mit der Juniorforschungs-gruppe Strukturbildung auf kleinen Skalen wurde eine neue Anlage zur asymmetrischen Fluß-Feld-Fluß-Frak-ti onierung (AF4) mit 18-Winkel-Licht-streu- (MALS), Brechungsindex- (RI) und variablen Wellenlängendetektor (VWD) installiert, da die üblichen SEC-/GPC-Methoden zur Charakterisierung der Molmassenverteilungen von Na-noparti keln und verzweigten Poly-meren und Biomolekülen nicht bzw. nur bedingt einsetzbar waren. Erste Trennungen an Gold-Supraparti keln in wässrigen Emulsionen detekti ert mit stati scher Lichtstreuung zeigten 2 Frakti onen von Teilchengrößenver-teilungen von ca. 40 nm und im Be-reich von mehreren Hundert nm.

Im Rahmen des BMBF-Projektes „Bio-kompati bilität von Nanoparti keln für die Medizintechnik, Diagnosti k und

Silbernanoparti keln und Silberionen durch Messung des zellassoziierten Ge-samtsilbergehaltes zu quanti fi zieren. Dazu wurden sogenannte A549-Zellen mit Silbernanoparti keln bzw. Silbernit-rat unterschiedlich lang inkubiert und nachfolgend die gefriergetrockneten Proben mit solid-GF(Graphitrohrofen)-AAS und die salpetersauren Waschlö-sungen mit GF-AAS und / oder ICP-OES analysiert. Es zeigte sich, dass bedingt durch die Inhomogenitäten des gefrier-getrockneten Zellmaterials, die auch durch nachfolgendes Mörsern dieser Proben nicht zufriedenstellend besei-ti gt werden konnten, die direkte solid-Technik nicht einsetzbar ist, da die re-lati ven Standardabweichungen bis zu 50 % betrugen. Die Nachweisgrenze für Ag im GF-AAS (Wandatomisierung, 338,3 nm, 3,0 mA, 1,2 nm Spalt) für fl üssiges Zellmedium wurde zu 5 pg/g experimentell ermitt elt, so dass trotz Verdünnung geringste Ag-Mengen in den Lungenzellen nachweisbar sind.

Für den Programmbereich Biominera-lisati on wurde eine Methode zur gas-chromatographischen Besti mmung von Sacchariden (Kohlenhydraten) eta-bliert. Dazu müssen die Kohlenhydrate

Die Servicegruppe Chemische Analyti k umfasst die Bereiche Chromatographie (HPLC, LC/MS, GC, GC/MS), Atomspek-trometrie (AAS, ICP-OES) und NMR-Spektroskopie (fl üssig und Festkörper).

Im Berichtszeitraum 2010 wurden vom Servicebereich chemische Analyti k ca. 70 % der analyti schen Arbeiten für interne Forschungsaufgaben und lau-fende Projekte des INM, ca. 25 % für Kooperati onen mit der Universität des Saarlandes und ca. 5 % für externe Auf-traggeber durchgeführt.

Neben den analyti schen Untersuchun-gen zu laufenden Industrieprojekten und Grundlagenforschungen des INM lag ein weiterer Schwerpunkt auf der Anpassung, Erweiterung und Opti mie-rung der bestehenden Methoden an die Anforderungen der neuen, haupt-sächlich biologisch orienti erten Arbeits-gruppen, die im Folgenden anhand von einigen Beispielen erläutert werden.

In Zusammenarbeit mit der Juniorfor-schungsgruppe Nano Zell Interakti onen wurden umfangreiche Messserien zur Silberanalyti k in menschlichen Zellen (Lungenepithel) durchgeführt. Ziel die-ser Analysen ist es, die Aufnahme von

Servicegruppe Chemische Analyti k / Service group Chemical Analysis

Dr. Claudia Fink-Straube

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Therapie“ wurde vom Programmbe-reich CVD/ Biooberflächen sogenann-tes PICS (ein Reaktionsprodukt aus Methoxy-Polyethylenglykol (mPEG) und Isocyanatopropyltriethoxysilan [ICPTEOS], Bild 2) hergestellt, welches an einem Kettenende durch eine Triet-hoxysilylgruppe modifiziert ist und da-durch kovalent an SiO2-Nanopartikel binden kann. Dadurch können die Na-nopartikel in z.B. biologischen Materi-alien stabilisiert werden. Die Synthese des PICS wurde mit FTIR-Spektrosko-pie, 1H-NMR und 13C-NMR (Bild 3) un-tersucht.

Die 1H- und 13C-NMR-Experimente zeigten keine signifikanten Änderun-gen an den Triethoxysilylgruppen, was darauf hinweist, dass keine Nebenre-aktionen wie z. B. Hydrolyse/ Konden-sation oder Umesterung mit den Hy-droxygruppen des mPEG stattfinden. Sowohl in den 1H-Spektren als auch in den 13C-Spektren konnten PICS und das Harnstoffderivat als Nebenprodukt semiquantitativ nachgewiesen wer-den. Die Senkung des Nebenproduk-tes durch Einsatz eines Katalysators konnte NMR-spektroskopisch verfolgt werden.

Bild 2: Herstellung von PICS aus ICPTEOS und mPEG (Kettenlänge 750 Da) mit Nebenreaktion (Hydrolyse des ICPTEOS).

Bild 3: 13C-NMR Spektren der Edukte ICPTEOS (Isocyanatogruppe 123,31 ppm, unten) und mPEG (HO-CH2 61,94 ppm, Mitte) sowie des Hauptproduktes PICS (Urethangruppe 157,14 ppm, oben) und des Harnstoff-Nebenproduktes (161,91 ppm, oben).

Bild 1: Analyse von 8 üblichen Kohlehydraten als Alditolacetat-Derivate auf einer ZB1701-Säule (30 m Länge, 0,25 mm Durchmesser, 250 µm Filmdicke), jeweils 2 µl Alditol-Mix unterschiedlicher Konzentration in Essigsäureethylester, isotherm bei 200 °C.

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Störfeldern und Gebäudeschwingun-gen haben gezeigt, dass innerhalb der bestehenden INM-Baulichkeiten kein geeigneter Raum entsprechend den geforderten Rahmenbedingungen ver-fügbar ist. Das neue Mikroskop wird deshalb in einem noch zu errichtenden Anbau untergebracht werden. Die Pla-nungsarbeiten konnten 2010 weitge-hend abgeschlossen werden.

Die Hauptakti vitäten der Physikali-schen Analyti k gliedern sich in all-gemeine Serviceleistungen wie die Gerätebetreuung, Justi erung und Ka-librierung der Geräte, Einweisung und Schulung von Gerätenutzern, sowie Serviceleistungen für die Programm-bereiche des INM und Kooperati onen im Rahmen von Projekten mit internen und externen Partnern. An umfang-reicheren laufenden Akti vitäten 2010 sind zu nennen:

und Methodik weiter zu entwickeln, wurde 2010 das aus dem Jahr 1992 stammende Rasterelektronenmikros-kop durch ein leistungsfähiges HR-SEM neuester Bauart ersetzt (JSM 7500F mit kalter FEG (Field Emission Gun); Aufl ösung 1.0 nm bei 15 kV; 1.4 nm bei 1 kV). Durch das erreichbare Aufl ö-sungsvermögen insbesondere im nie-derenergeti schen Bereich haben sich unsere Möglichkeiten zur Charakteri-sierung von Nanoparti keln und Ober-fl ächenstrukturen deutlich verbessert.

In Vorbereitung der 2011 anstehenden Installati on eines neuen analyti schen Raster-Transmissions-Elektronenmi-kroskops (JEOL JEM-ARM 200F TEM/STEM mit kalter Feldemissionskathode (C-FEG), Cs-Korrektor zur Korrektur der sphärischen Aberrati on des Kondensor-systems, EDS und EELS (electron energy loss spectroscopy)/GIF (Gatan Imaging Filter)-Spektrometer; Punktaufl ösung in STEM <0.08 nm) wurden umfang-reiche Planungsarbeiten erforderlich. Feldmessungen betreff s magneti schen

In der Physikalischen Analyti k sind die Bereiche Elektronenmikroskopie und Röntgenanalyti k als zentrale Service-einrichtungen zusammengefasst. Die Röntgenanalyti k ist mit drei Röntgen-diff raktometern (XRD) neuester Bauart für konventi onelle Pulver-XRD, Vier-Kreis-XRD speziell für Dünnschicht-Cha-rakterisierung, Hochtemperatur-XRD für in situ-Messungen sowie mit Fluo-reszenzspektrometer (XRF) für quanti -tati ve chemische Analyse ausgestatt et. Am INM stehen mit derzeit einem 200 kV-Transmissions-Elektronenmikroskop (TEM), zwei Raster-Elektronenmikros-kopen (SEM) für Hoch- und Niedervaku-um (ESEM) sowie zwei Raster-Kraft mik-roskopen (AFM) und einem konfokalen Laser-Raster-Mikroskop (CLSM) Einrich-tungen für eine umfassende Charakteri-sierung nanostrukturierter Materialien bezüglich deren Struktur, Phase, Mor-phologie und chemischer Zusammen-setzung zur Verfügung.

Im Zuge unserer Bestrebungen, die Analyti k bezüglich Geräteausstatt ung

Servicegruppe Physikalische Analyti k / Service Group Physical Analysis

Dr. Herbert Schmid

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• Charakterisierung von Inversions-Domänenstrukturen (IDB: Inversion Domain Boundary) in Fe- und In-dotiertem ZnO mittels HR-STEM-Abbildung mit atomarer Auflösung (HAADF: High-Angle Annular Dark-Field und ABF: Annular Bright-Field STEM Imaging).

Externe Kooperationen:

• ESEM-Untersuchungen zur Partikel-größenverteilung polymerer Nanop-artikel in Wasser für Drug-Delivery-Systeme (Pharmazie, Universität des Saarlandes),

• Charakterisierung von SnO2-Nano-drähten auf TiO2-Substraten mittels hochauflösender TEM-Methoden (Anorganische Chemie, Universität Köln),

• Analytische TEM-Untersuchungen zur Struktur von Ni-Clustern in Ni/a-C-Sensorschichten (HTW – Hoch-schule für Technik und Wirtschaft, Saarbrücken).

INM-interne Kooperationen/Serviceleistungen:

• Charakterisierung von Nanoparti-keln und Nanowires/-rods bezüglich Struktur, Kristallinität, Morphologie, Größenverteilung und chemischer Zusammensetzung,

• Phasenanalyse in verschiedenen Perovskit-Strukturen mittels XRD-Methoden,

• Aufklärung von Core-Shell-Struktu-ren mittels hochauflösender TEM in verschiedenen Metall/Metalloxid-Systemen,

• Untersuchungen zur Strukturbildung von Ag-Nanopartikeln mittels TEM, SEM und WET-STEM,

• ESEM-Untersuchungen zur Wech-selwirkung von Nanopartikeln (Ag, ZrO2) in biologischen Materialien.

Methodische Entwicklungen:

• Analyse zweidimensionaler kolloida-ler Kristallstrukturen (2D-Partikel-Ensembles) aus der Paarverteilungs-Korrelationsfunktion,

93

die Messwerterfassung zur Charakte-risierung elektrischer Materialeigen-schaft en. Weiterhin führt die Service-gruppe im Rahmen einer Kooperati on die Werkstatt aufgaben für den Lehr-stuhl „Technische Physik“ der Universi-tät des Saarlandes durch. Einen hohen Stellenwert in der Servicegruppe hat die Ausbildung, was sich auch in dem mit 20 % der Mitarbeiter hohen Anteil an Auszubildenden zeigt.

Durch die neuen Programmberei-che des INM sind zusätzliche Aufga-ben im Bereich der Mikromechanik an die Servicegruppe herangetragen worden. Zur Erfüllung dieser Anfor-derungen wurde der Maschinenpark um eine 5-Achs-Präzisionsfräsmaschine von Röders GmbH erweitert. Mit die-ser Hochgeschwindigkeitsfräsmaschine wurden zum Beispiel Teile im Hartbe-arbeitungssektor sowie Gießformen im Mikrometerbereich mit einem

Das Hauptarbeitsgebiet der Service-gruppe liegt in der Entwicklung und im Bau von wissenschaft lichen Anlagen und Komponenten für die INM-Pro-grammbereiche im Rahmen von Pro-jekten und im Bereich der Grundlagen-forschung. Die Bandbreite reicht hier-bei von kleinen Laborgeräten bis hin zu großen Pilotanlagen. Aus den Vorgaben der Forschung werden Konzepte ent-wickelt, mit denen nach Präzisierung der Anforderungen eine Konstrukti on erstellt wird. Planung, Konstrukti on und Bau erfordern eine enge Verzah-nung mit den wissenschaft lichen Ab-teilungen des Hauses. Die prakti sche Umsetzung erfolgt in den Werkstätt en durch weitestgehend eigene Ferti gung sowohl von individuellen Steuerungen und Soft wareentwicklungen als auch der mechanischen Herstellung der einzelnen Komponenten einschließlich des Zusammenbaus zur komplett en Anlage. Ein weiteres Arbeitsgebiet ist

Servicegruppe Engineering / Service Group Engineering

Dietmar Serwas

4-bis 5-fachen Aspektverhältnis bei hohen Anforderungen an Oberfl ä-chenqualität und Genauigkeit herge-stellt.

Damit steht folgende Ausstatt ung zur Verfügung:

• Präzisionsdrehmaschine,• 5-Achs-Präzisionsfräsbearbeitungs-

zentrum,• 6 -Achs-Roboter-Wasserstrahl -

schneidanlage,• 3D-CAD-System CATIA V5,• CAM für vorgenannte Anlagen ein-

schließlich Simulati onsmodule,• SPS-Programmiergerät/Software

Siemens und WAGO,• Messmöglichkeit für Leitf ähigkeit,

Dielektrizitätseigenschaft en, Durch-schlagsspannungen.

94

Service Group Materials Testing/Powder Synthesis / Servicegruppe Werkstoffprüfung/Pulversynthese

Karl-Peter Schmitt, Robert Drumm

Der Servicebereich Werkstoffprüfung/Pulversynthese umfasst hauptsächlich die Prüfverfahren, mit denen das Ver-halten und die Werkstoffkenngrößen von normierten Werkstoffproben oder fertigen Bauteilen unter mechani-schen, thermischen oder chemischen Beanspruchungen ermittelt werden. Die verwendeten mechanischen Prüf-verfahren dienen zur Charakterisie-rung der Festigkeit, des Verformungs- und Bruchverhaltens sowie der Härte und des Verschleißwiderstandes von Werkstoffen. Der Servicebereich un-terstützt die Programmbereiche bei verfahrenstechnischen Entwicklungen zum Up-Scaling bestehender Pulver-synthesen in den Technikumsmaßstab. Er führt Synthesen sowie Dispergie-rungen von nanoskaligen Partikeln im Auftrag der Programmbereiche sowie externer Kunden durch.

95

Fakten und Zahlen /Facts and Figures

96

97

turprogramme des Bundes geförder-ten Maßnahmen (keine Erträge 2010; Vorjahr 306 T€) sowie geringeren sons-ti gen Erträge im Jahr 2010 (-208 T€).

Die Bilanzsumme der Gesellschaft zum 31. Dezember 2010 beträgt 20.403 T€; gegenüber dem Vorjahr (18.745 T€) eine Erhöhung um 1.658 T€. Sowohl das Anlagevermögen (+1.103 T€) als auch das Umlaufvermögen (+667 T€) haben sich gegenüber dem Bilanzsti ch-tag des Vorjahres erhöht. Die Investi -ti onstäti gkeit (3.471 T€) übersti eg im Geschäft sjahr 2010 deutlich die Ab-schreibungen in Höhe von 2.401 T€. Die Verbindlichkeiten der Gesellschaft beliefen sich zum Bilanzsti chtag auf 2.171 T€ gegenüber 1.238 T€ im Vor-jahr.

Finanz- und Ertragslage / Vermögenslage der Gesellschaft

Als Forschungseinrichtung der Leibniz-Gemeinschaft hat das INM auch im Haushaltsjahr 2010 eine gemeinsame Förderung durch den Bund und die Länder erhalten. Diese belief sich auf 15.480 T€; hiervon 10.514 T€ zur Fi-nanzierung von Personal- und Sachauf-wendungen, sowie 4.966 T€ für erfor-derliche Neu- und Ersatzinvesti ti onen.

Die nominale Steigerung der Zuwen-dung gegenüber dem Vorjahr um 1.224 T€ liegt mit rd. 8,6 % etwas unterhalb der Zuwachsrate der Leibniz-Gemein-schaft für den Gesamtzuwendungsbe-darf aller Einrichtungen im Jahr 2010 in Höhe von 10,3 %. Im Rahmen der Bund-/ Länder-Verhandlungen erfolg-ten für die Insti tute der Leibniz-Ge-meinschaft einmalige bedarfsgerechte Plafonderhöhungen. Dem INM wurden zudem weitere Finanzmitt el zum Auf-bau neuer Forschungsschwerpunkte bewilligt.

Im Geschäft sjahr 2010 erzielte das INM eigene Erlöse aus Forschung und Ent-wicklung sowie sonsti ge betriebliche Erträge in Höhe von 2.853 T€ (Vorjahr: 3.807 T€). Die Industrieerlöse aus For-schung und Entwicklung sowie aus Li-zenzvereinbarungen beliefen sich hier-bei auf 884 T€ (Vorjahr: 1.181 T€). Im Rahmen öff entlicher Projektf inanzie-rungen erzielte das INM im Jahr 2010 Erlöse in Höhe von 1.650 T€ (Vorjahr: 1.793 T€). Sonsti ge Erträge resulti erten im Geschäft sjahr 2010 überwiegend aus der Weiterbelastung von Gebäu-de-, Patent- und sonsti gen Kosten.

Der Gesamtumsatz 2010 der Gesell-schaft betrug 16.930 T€ (Vorjahr: 17.916 T€). Der Rückgang resulti ert in erster Linie aus den geringeren Erträ-gen aus Forschung und Entwicklung (-440 T€), der 2009 erfolgten Ferti g-stellung der im Rahmen der Konjunk-

Statusbericht / Status report

98

Personalentwicklung

Die Anzahl der Beschäftigten im Jahr 2010 ist gegenüber 2009 leicht an-gestiegen. So waren Ende 2010 190 Mitarbeiter (164 Vollzeitäquivalente) gegenüber 185 Mitarbeitern (162 Voll-zeitäquivalente) Ende 2009 am INM tätig. Hiervon waren 47 Mitarbeiterin-nen und Mitarbeiter (dies entspricht 38 Vollzeitäquivalenten) im Drittmit-telbereich beschäftigt. Die Anzahl der Auszubildenden stieg wieder von sechs auf neun; der Anteil der Mitarbeiterin-nen und Mitarbeiter im Verwaltungs-bereich / Sekretariate / cc-NanoChem sank um einen Prozentpunkt auf 15,8 %. Der Anteil der Doktoranden / Diplomanden erhöhte sich von 11,4 % auf 13,2 %, der Anteil der Hilfswissen-schaftler blieb mit 6,8 % nahezu kon-stant. Gegenüber dem Vorjahr verrin-gerte sich der Anteil der wissenschaft-lichen und graduierten Mitarbeiter um 2,5 Prozentpunkte auf 32,1 %, wäh-rend der Anteil der Servicemitarbeiter und der Mitarbeiter im technischen Bereich mit 27,4 % gegenüber 27,6 % in 2009 nahezu konstant blieb.

99

of the economic sti mulus packages of the federal government (no profi ts in 2010, 306 T€ in the previous year) as well as lower other profi ts in 2010 (-208 T€).

The balance sheet total of the corpo-rati on is 20,403 T€ on 31 December 2010, which is an increase of 1,658 T€ compared to the preceding year (18,745 T€). Both the non-current as-sets (+1,103 T€) and the current as-sets (+667 T€) increased compared to the balance sheet day of the previous year. The investment acti vity of the fi scal year 2010 (3,471 T€) exceeded signifi cantly the write-off s amounti ng to 2,401 T€. The liabiliti es of the cor-porati on amounted to 2,171 T€ as of the balance sheet date (1,238 T€ in the previous year).

Financial and income situati onof the corporati on

As a research insti tute of the Leibniz Associati on, INM obtained common fi nancial support from the federal gov-ernment and the federal states in the fi nancial year 2010. This amounted to 15,480 T€; 10,514 T€ of those were used for fi nancing personnel and ma-terials expenses and 4,966 T€ for nec-essary new and replacement invest-ments.

The fi nancial contributi on increased nominally by 1,224 T€ compared to the previous year. It is roughly 8.6% and thus slightly below the overall growth rate of the Leibniz Associati on (10.3%). In negoti ati ons between the German government and the federal states non-recurring needs-based budget increases were provided for the in-sti tutes of the Leibniz Associati on. Moreover, INM was granted further fi nancial means for the establishment of new areas of research.

In the fi nancial year 2010, INM gener-ated own proceeds from research and development as well as from other op-erati ng income amounti ng to 2,853 T€ (3,807 T€ in the preceding year). The industry revenues from research and development as well as from patents/licences hereby amounted to 884 T€ (1,181 T€). Within the scope of public project fi nancing, INM generated pro-ceeds amounti ng to 1,650 T€ in 2010 (1,793 T€). Other income in the fi nan-cial year 2010 resulted mainly from cost transfer for buildings, patents and other costs.

In 2010, the total turnover of INM added up to 16,930 T€ (17,916 T€ in the previous year). The reducti on results primarily from the lower profi ts from research and development (-440 T€) and the completi on of structural meas-ures in 2009 funded within the scope

100

Personnel development

In comparison to 2009, the number of employees increased moderately in 2010. At the end of 2009, 190 em-ployees (164 full-time equivalents) worked at INM compared to 185 em-ployees (162 full-time equivalents) in the preceding year. 47 employees (38 full-time equivalents) were financed by third-party funds. The number of ap-prentices rose again from six to nine, whereas the proportion of the staff members of the administration, the secretarial offices and cc-NanoChem decreased by 1 percent point to 15.8%. The proportion of doctoral candidates and other graduate students rose from 11.4% to 13.2%, whereas the propor-tion of the graduate assistants almost remained constant at 6.8%. Compared to the previous year, the proportion of scientific and graduated employees decreased by 2.5 percent points to 32.1%. The proportion of the manual workers and the employees in techni-cal services almost remained constant at 27.4% compared to 27.6% in 2009.

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Mitglieder des wissenschaft lichen Beirats / Members of the Scienti fi c Board

Stand / Status: 31.12.2010

Prof. Dr.-Ing. Horst HahnGeschäft sführender Direktor, Insti tut für Nanotechnologie (INT)Karlsruher Insti tut für Technologie– Vorsitzender –

Prof. Dr. Rainer BirringerLehrstuhl für Technische PhysikUniversität des Saarlandes

Prof. Dr. Ludwig GaucklerInsti tut für Nichtmetallische Werkstoff eETH, Zürich, Schweiz

Dr.-Ing. Klaus HarsteVorstandsvorsitzenderSaarstahl AG, Völklingen

Dr. Christi ane Friederike Lindner Abteilungsleitung (CR/ARM) Fa. Robert Bosch GmbH, Stutt gart

Prof. Dr. Marti n MöllerDirektor des DWI undLehrstuhl für Texti lchemie und Makromole-kulare ChemieRWTH Aachen

Prof. Dr. Andreas MortensenEPFL, Lausanne, Schweiz

Prof. Dr. Erich SackmannLehrstuhl für Biophysik Technische Universität München, Garching

Prof. Dr. Robert F. SingerLehrstuhl Werkstoffk unde und Technologie der MetalleUniversität Erlangen-Nürnberg

Prof. Dr. Günther TränkleDirektorFerdinand-Braun-Insti tut, Leibniz-Insti tut für Höchstf requenztechnik, Berlin

Akti vitäten in Gremien / Acti viti es in committ ees

Prof. Dr. Eduard Arzt Mitglied der Deutschen Akademie der Na-turforscher Leopoldina

Mitglieder des Kuratoriums /Members of the Board of Directors

Stand / Status: 31.12.2010

Staatssekretär Peter HauptmannMinisterium für Wirtschaft und Wissenschaft – Vorsitzender –

Dr. Gerhard FeltenGeschäft sleiter Zentralbereich Forschung und VorausentwicklungRobert Bosch GmbH, Stutt gart

Jochen FlackusLeiter Abteilung C - TechnologieMinisterium für Wirtschaft und Wissen-schaft des Saarlandes

Prof. Dr.-Ing. Horst HahnGeschäft sführender Direktor, Insti tut für Nanotechnologie (INT)Karlsruher Insti tut für Technologie

Dr. Max HäringVorstandsvorsitzender a. D.Landesbank Saar Girozentrale, Saarbrücken

Prof. Dr. Volker LinneweberPräsident der Universität des Saarlandes– Stv. Vorsitzender –

Prof. Dr. Dr.-Ing. E.h. Kurt MehlhornWissenschaft licher DirektorMax-Planck-Insti tut für Informati k, Saarbrü-cken

Prof. Dr.-Ing. Frank MücklichLehrstuhl für Funkti onswerkstoff eUniversität des Saarlandes

Dr. Peter W. de OliveiraWissenschaft licher MitarbeiterINM gGmbH

Ralf ZastrauVorstandsvorsitzenderNanogate AG, Gött elborn

MinRat Dr. Herbert ZeiselLeiter Referat 511 – Neue Werkstoff e, Na-notechnologieBundesministerium für Bildung und For-schung, Bonn– Stv. Vorsitzender –

Korrespondierendes Mitglied der Öster-reichischen Akademie der Wissenschaft en Mitglied bei: • Aufsichtsrat des LKR Leichtmetallkompe-

tenzzentrum Ranshofen GmbH • Strategiebeirat, Material Engineering

Centre Saarland (MECS), Saarbrücken • Professorial Committ ee, IST Austria,

Wien • Wissenschaft licher Beirat der Alfried

Krupp von Bohlen und Halbach Sti ft ung, Essen

• Internati onaler Beirat der Christi an-Dop-pler-Gesellschaft , Wien

• Review Panel, Energy Fronti er Research Centers (EFRC), Department of Energy, USA (Juli 2010)

• Scienti fi c Committ ee, SPIE-Konferenz „Smart Sensors, Actuators and MEMS“, Prag 2011

• Scienti fi c Committ ee, Konferenz „Smart Structures and Materials“ (SMART‘ 11), Saarbrücken 2011

• Scienti fi c Committ ee, geplantes IUTAM Symposium „Mechanics of Soft Acti ve Materials“, Technion Israel Insti tute of Technology 2011/2012

• Organisator, Workshop „Bioinspired ad-hesion: from geckos to new products?“, 7.-9. Juli 2010, Saarbrücken

• Editor der Reviewzeitschrift „Progress in Materials Science“, Oxford, UK

Gast-Editor Advanced Engineering Materi-als, Heft OS/2010 Mitglied im Editorial Boards/Advisory Boards der Zeitschrift en:„MRS Bulleti n of the Materials Research Society“, USA, „Advanced Engineering Ma-terials“, Weinheim, „Internati onal Journal of Materials Research“, München, „Mate-rials Science and Engineering C: Materials for Biological Applicati ons“, Elsevier, „En-cyclopedia of Nanotechnology“, Springer, „Materials Seience and Technology“, Lon-don/UK Referee bei Zeitschrift en (Auswahl): Proceedings of the Royal Society, The Journal of Adhesion, Journal of Materials Science, Journal of Strain Analysis for Engi-neering Design, Materials Science and En-gineering: R: Reports, Advanced Materials Gutachtertäti gkeit bei (Auswahl): Alexander von Humboldt-Sti ft ung, Bonn; DFG Deutsche Forschungsgemeinschaft , Bonn; Max Planck Insti tute of Colloids and Interfaces, Potsdam; IWM -Fraunhofer Insti tut für Werkstoff mechanik, Freiburg;

Mitglieder des Kuratoriums / Members of the Board of DirectorsMitglieder des wissenschaft lichen Beirats / Members of the Scienti fi c BoardAkti vitäten in Gremien / Acti viti es in committ ees

102

Dr. Tobias Kraus Referee bei Zeitschriften: Applied Physics Letters, Tribology Letters, Chemistry of Material, Journal of Colloids and Interface Science, Journal of Physics and Chemistry of SolidsGutachtertätigkeit für den Schweizer Na-flonal Fonds (SNF)

Dr. Karsten Moh Geschäftsführer bei cc-NanoChem e. V.Gutachtertätigkeit bei Machbarkeitsstu-dien für NanoBioNet e.V.

Dr. Thomas Müller Referee bei Zeitschrift Thin Solid Films

Dr. Peter W. de Oliveira Mitarbeit im Round Table Lateinamerika des BMBF Referee bei Zeitschrift Materials Letters

Dr. Mario QuilitzMitarbeit im Round Table Lateinamerika des BMBF Referee bei Zeitschriften: Solid State lo-nics, Electrochemical and Solid State Let-ters

Dr. Peter Rogin Referee bei Zeitschrift Plasma Processes & Polymers

Dr. Roland Rolles Mitglied bei: • Beirat, NanoBioNet e. V. • Beirat, Lucie-Bolte-Stiftung, Dillingen

Dr. Andreas SchneiderReferee bei Zeitschriften: Physica E, Philo-sophical Magazine Letters

Prof. Dr. Dr. Daniel J. Strauss Mitglied bei: • Empower Deutschland / Cluster Medizin-

technik • Cognitive Neuroscience Society CNS • Institute of Electrical and Electronic Engi-

neers IEEE • Engineering in Medicine and Biology So-

ciety EMBS • Society for Industrial and Applied Mathe-

matics, SIAM Referee bei Zeitschriften: Experimental Brain Research, Biomedi-cal Signal Processing and Control, Neu-roimage, Journal of Neuroscience Me-thods, Artificial Intelligence in Medicine, IEEE Trans. On Neural Networks, IEEE

Australian Academy of Sciences; Universi-tät für Bodenkultur Wien; Netherlands Or-ganisation for Seientific Research (NWO); Biotechnology and Biological Sciences Research Council (BBSRC), UK; Massachu-setts Institute of Technology, USA; Ithaca College, Ithaca, NY, USA

Dr. Carsten Becker-Willinger Gutachtertätigkeit bei Forschungsanträgen „Forschungsverbund Baden-Württemberg“

Prof. Dr. Roland Bennewitz Adjunct Professor, Physics Department der McGill University, Montreal, Canada Honorarprofessor der Universität des Saarlandes, Saarbrücken Organisator Nanobrücken - Nanomecha-nical Testing Workshop and Hysitron User Meeting, INM -Leibniz Institute for New Materials, Saarbrücken (Germany), 25.02.-26.02.2010 Co-Organisator, Symposium “Nanotribo-logie”, DPG Frühjahrstagung, Regensburg (Germany), 21.03.-26.03.2010 Chair, FANAS 2010 Conference on Friction and Adhesion in Nanomechanical Systems, Saarbrücken (Germany), 25.10.-27.10.2010 Referee bei Zeitschriften: Beilstein Nano, Carbon, Nature Materials, Progress in Ma-terials Science, Physical Review Letters, Thin solid films, Tribology letters Gutachtertätigkeit für: US Department of Energy, University of Massachusetts, Tur-kish Academy of Science

Jochen Flackus Vorstandsvorsitzender des NanoBioNet e.V.Gründungsmitglied von Saarland Empo-wering Nano Editor der Zeitschrift Empowering Nano

Dr. Annette Kraegeloh Conference Chair, 8th International Confe-rence and Workshop on Biological Barriers -in vitro Tools, Nanotoxicology, and Nano-medicine, Universität des Saarlandes, Saar-brücken, Germany, March 21-April 1st, 2010 Conference Chair, Session “Potential risks of nanomaterials”, NanoMed -7th Interna-tional Conference on Biomedical Applica-tions of Nanotechnology, Berlin, Germany, December 2-3, 2010 Referee bei Zeitschriften: ACS Nano, Microbiology, Nanotoxicology Gutachtertätigkeit für die Swiss National Science Foundation

Trans. on Biomedical Engineering, IEEE Trans. on Neural Systems & Rehabilitati-on Engineering, Medical Engineering and Physics; Annals of Biomedical Engineering, IEEE International Conference Neural Engi-neering, IEEE International Conference of the Engineering in Medicine and Biology Society, Computers in Medicine & Biology Gutachtertätigkeit für Medical Research Council, UK, The Netherlands Organisati-on for Health Research and Development, The Netherlands

Prof. Dr. Dr. h. c. Michael Veith Berater des INM (ab 01.07.2010) Lehrstuhl für Anorganische und Allge-meine Chemie der UdS Saarbrücken (bis 31.03.2010, dann: Seniorprofessor für Anorganische und Allgemeine Chemie der UdS Saarbrücken) Berater der Universität Lyon, France Bevollmächtiger der DFH für den Stu-dentenaustausch mit Strasbourg, France (ECPM) Externes Beratungsmitgiied, LCC Toulou-se, France Sprecher, Internationales Gra-duiertenkolleg GRK 532 Leiter Frankreichzentrum, Universität des Saarlandes, Saarbrücken Vorstand des AGeNT-D Netzwerk der na-tionalen Kompetenzzentren für Nanotech-nologien und Nanoanalytik 1. Vorsitzender des cc-NanoChem Vorstandsmitglied, International Ring Sys-tems (IRIS), International Meetings: Ger-manium, Tin, Lead (GTL) Mitglied bei: • Akademie der Wissenschaften und der

Literatur, Mainz • Deutschen Akademie der Naturforscher

Leopoldina, Halle • Fellow of the Royal Society of Chemistry,

London, UK • Wissenschaftlicher Beirat, Papiertechni-

sche Stiftung PTS, München • Ecole Doctorale Metz-Nancy, France • Expertengruppe Metropolprojekt Saar-

brücken • Moselle Est, France • Verwaltungsrates der EEIGM Nancy,

France • Arbeitsausschuss Angewandte Anorgani-

sche Chemie DECHEMA e.V • International Advisory Board der Zeit-

schrift für Anorganische und Allgemeine Chemie ZAAC

• Steering Commitee NanoMed Berlin

103

Philip Egberts3. Posterpreis, Workshop „Nanobrücken 2010“, Saarbrücken, 25.-26.02.2010

Dr. Griselda Guidoni2. Posterpreis, “CAMTECH II – Symposium on Fine-Scale Mechanical Characterisati -on and Behaviour”, Notti ngham (UK), 29.-30.03.2010

Florian HausenForschungssti pendium der Max-Buchner-Forschungssti ft ung

Elmar Kroner2. Posterpreis, Workshop „Bioinspired ad-hesion: from geckos to new products“, Saarbrücken, 7.-9.07.2010

Dr. Sabrina Schübbe, Dr. Christi an Schu-mann3. Preis, Fotowett bewerb von NanoBioNet e.V. und cc-NanoChem

Prof. Dr. Dr. h.c. Michael Veith und Ex-terneInterregionaler Wissenschaft spreis 2010 „Exzellenznetze in der Großregion“ für das Europäische Graduiertenkolleg „Physikali-sche Methoden in der strukturellen Charak-terisierung neuer Materialien“

Habilitati on / Habilitati onStrauss, Prof. Dr. Dr. Daniel J.On the Multi scale Modeling and Analysis of Neural Correlates of Att enti onUniversität des Saarlandes, Medizinische Fakultät

Abgeschlossene Dissertati onen /Completed doctoral thesesDissertati onen am INM / Doctoral theses at INM

Bender, MichaelSynthese neuarti ger Single-Source-Precur-soren für die Abscheidung piezoelektrischer Bleizirkonatti tanat (PZT)-Schichten mitt els chemischer Gasphasenabscheidung (CVD)Universität des Saarlandes, Diss. 2010Prof. Dr. Dr. h.c. Michael Veith

Bubel, CarstenSynthese eines neuarti gen Precursorsys-tems und dessen Applikati on zur Herstel-lung von Indium-Zinnoxid-Schichten

Mitglied im Editorial Board der Zeitschrif-ten: New Journal of Chemistry (NJC), Comptes Rendus. Synthesis and Reacti vity in Inorganic and Metal-Organic Chemistry (European Ed.) Referee bei Zeitschrift en: Acta Biomate-rialia, Angewandte Chemie, Chemistry of Materials, Zeitschrift für Anorganische und Allgemeine Chemie ZAAC, Dalton Transacti ons, Inorganic Chemistry, Mo-natsheft e für Chemie Gutachtertäti gkeit bei: Deutsche For-schungsgemeinschaft (DFG), Deutsche Akademie der Naturforscher Leopoldina, Qiagen GmbH (Innovati on Award), Alexand-er-von-Humboldt-Sti ft ung (Sti pendien), Uni-versität des Saarlandes, UdS, Saarbrücken, College de France, Paris, German-Israeli-Foundati on for Scienti fi c Research and De-velopment, Evaluierung Insti tute of Selences Chimiques de Rennes (UMR 6226), The Ro-yal Society, London, Internati onal Center for Fronti er Research in Chemistry (FRC), ENO-VOS Deutschland AG, Universität Kassel

PD Dr. habil. Ingrid Weiss Privatdozenti n für Biochemie an der Uni-versität RegensburgGutachtertäti gkeit bei: Agence Nati onale de la Recherche (ANR), France, Minerva Foundati onReferee bei Zeitschrift en: JACS, Biomacro-molecules, Journal of Structural Biology, BMC Proteome Science, ChemBioChem, Materials Science and Engineering C/D, Soft -Matt er, Crystal Growth and Design, Ameri-can Mineralogist, CBM-Cahiers de Biologie Marine, Nature Chemical Biology, Micros-copy and Microanalysis, Journal of the Me-chanical Behavior of Biomedical Materials

Dr. Alexandra Witt mar Referee bei Zeitschrift Journal of Non-Cry-stalline Solids

Dr. Matt hias Witt mar Referee bei Zeitschrift Corrosion Science

Auszeichnungen / AwardsProf. Dr. Eduard Arzt John Dorn Memorial Lecture 2010, Nor-thwestern University, Evanston (IL), USA

Prof. Dr. Eduard Arzt und ExternePreisträger im Innovati onswett bewerb Me-dizintechnik 2010 mit „FixNaht – Fixieren-des chirurgisches Nahtmaterial“

Universität des Saarlandes, Diss. 2010Prof. Dr. Dr. h.c. Michael Veith

Rabung, BenjaminElektrochemische Synthese von nanoskali-gem Zinkoxid und Indium-Zinn-Oxid sowie deren Vorstufen in einem wässrigen SystemUniversität des Saarlandes, Diss. 2010Prof. Dr. Dr. h.c. Michael Veith

Ullah Wazir, HameedHydrido/Chloro Aluminium Alkoxides and Metal (Al, Ge) Alkoxides – Synthesis, Charac-terizati on and Applicati ons for Preparati on of Novel Hydrogen Storage Nano-MaterialsUniversität des Saarlandes, Diss. 2010Prof. Dr. Dr. h.c. Michael Veith

Wohlfart, EllenNanopatt ering of Poly(ethelene terephala-te) by Plasma EtchingUniversi tät Stutt gart, Diss. 2010Prof. Dr. Eduard Arzt

Von INM-Wissenschaft lern betreute Dissertati onen / Doctoral theses supervised by INM scienti sts

Rödl, Florian Time-resolved diff racti on experiments on piezoelectric actuatorsUniversität Stutt gart, Diss. 2010Prof. Dr. E. Arzt

Schneider, Andreas Mechanical Properti es of Small-Scale BCC Metal StructuresUniversität Stutt gart, Diss. 2010Prof. Dr. E. Arzt

Sonnweber-Ribic, Petra Grain growth and texture evoluti on in cop-per thin fi lmsUniversität Stutt gart, Diss. 2010Prof. Dr. E. Arzt

Trenado, Carlos A Neural Field Model for Auditory Selecti ve Att enti on Neural CorrelatesUniversität des Saarlandes, Diss. 2010Prof. Dr. Dr. D. J. Strauss

Auszeichnungen / Awards Habilitati on / Habilitati on

Abgeschlossene Dissertati onen / Completed doctoral theses

104

Kirs, TatjanaProf. Dr. Dr. h.c. Michael Veith

Kolano, DavidProf. Dr. Dr. h.c. Michael Veith

Kroner, Elmar Prof. Dr. Eduard Arzt

Lacava, Johann Prof. Dr. Eduard Arzt

Lee, JuseokProf. Dr. Dr. h.c. Michael Veith

Lehnert, TobiasProf. Dr. Dr. h.c. Michael Veith

Martinez Miró, MarinaProf. Dr. Dr. h.c. Michael Veith

Moll, JanaProf. Dr. Dr. h.c. Michael Veith

Narr, KatharinaProf. Dr. Alexandra K. Kiemer

Paretkar, DadhichiProf. Dr. Eduard Arzt

Gastwissenschaftler / Guest ScientistsAkkan, Çagri KaanTürkei

Aktas, Dr. CenkTürkei

Ali, AwadelkareemSudan

Ali, Dr. BudimanRepublik Indonesien

Al-Kahlout, Dr. AmalPalästina

Araujo de Itriago, Yani CarolinaVenezuela

Balijepalli, Ram GopalIndien

Belot, Dr. CélineFrankreich

Canas, Natalia AndreaArgentinien

Abgeschlossene Bachelor- und Masterarbeiten / Completed bachelor and master theses

Ali, Awadelkareem AbdelrahmanSynthesis and Study of Thiosemicarbazones Metal Complexes as Anti-Cancer AgentsUniversität des Saarlandes, Master 2010Prof. Dr. Dr. h.c. Michael Veith

Canas, NataliaInfluence of surface roughness on the ad-hesion of biomimetic patterned surfacesUniversität des Saarlandes, Master 2010Prof. Dr. Eduard Arzt

Jochem, AljoshaSynthesis, modification and characterization of Gold Nanoparticles for STED MicroscopyUniversität des Saarlandes, Bachelor 2010Prof. Dr. Eduard Arzt

Mejia Trejo, Victoria LilianaMetal-PDMS hybrid systems for switchable adhesionUniversität des Saarlandes, Master 2010Prof. Dr. Eduard Arzt

Doktoranden / Doctoral StudentsAkkan, Çagri KaanProf. Dr. Mohamad Hammadeh, Universi-tätsklinikum des Saarlandes

Born, PhilipProf. Dr. Eduard Arzt

Brörmann, KatrinProf. Dr. Roland Bennewitz

Dufloux, CecileProf. Dr. Dr. h.c. Michael Veith

Egberts, PhilipProf. Dr. Roland Bennewitz

Hausen, FlorianProf. Dr. Roland Bennewitz

Held, ChristianProf. Dr. Roland Bennewitz

Jochum, MarlonProf. Dr. Dr. h.c. Michael Veith

Kasper, ChristophProf. Dr. Dr. h.c. Michael Veith

Castellanos, GracielaSpanien

Chen, SiKanada

Dufloux, CecileFrankreich

Eder, Dr. MagdalenaÖsterreich

Edongue, Dr. HervaisKamerun

Egberts, PhilipKanada

Egorov, Dr. YuriRussland

Garcia Morales, María ImmaculadaVenezuela

Girault, Dr. BaptisteFrankreich

Gosvami, Dr. Nitya NandIndien

Guidoni, Dr. GriseldaArgentinien

Gustiana, Wina W.Republik Indonesien

Haidar, AymanLibanon

Han, HyeyoungSüdkorea

Kamperman, Dr. MarleenNiederlande

Kirchner, Prof. Dr. HelmutFrankreich

Kirs, TatjanaRussland

Lacava, JohannFrankreich

Lee, JuseokSüdkorea

Lin, Dr. HechunChina

Abgeschlossene Bachelor- und Masterarbeiten / Completed bachelor and master theses

Doktoranden / Doctoral Students

Gastwissenschaftler / Guest Scientists

105

In: Proceedings of 32nd Internati onal Annu-al Conference IEEE Engineering in Medicine and Biology Society: “Merging Medical Hu-manism and Technology” (EMBC’10), Au-gust 31-September 04, 2010, Buenos Aires <Argenti na>, (2010), pp 6833-6836

E. Gnecco, R. Bennewitz, O. Pfeiff er, A. Socoliuc and E. Meyer Fricti on and wear on the atomic scale In: Springer Handbook of Nanotechnology (3rd Ed.), B. Bhushan Ed., Springer: Berlin [u. a.], 2010, pp 923-953

B. Heiland, A. S. Schneider, E. Arzt and I. M. WeissSkalenübergreifende Strukturanalyse an Anschliff en und Dünnschliff en von Seeohr-SchalenIn: Fortschritt e in der Metallographie - 13. Internati onale Metallographie-Tagung an der Montanuniversität Leoben, September 29-October 01, 2010, Leoben <Austria>, A. Kneissl and H. Clemens, Eds., (2010), pp 121-126

F. Hernandez-Ramirez, J. D. Prades, S. Barth, A. Romano-Rodriguez, S. Ma-thur, A. Tarancon, O. Casals, R. Jimenez-Diaz, J. Rodriguez, E. Pellicer, M. A. Juli, T. Andreu, S. Estrade, E. Rossinyol and J. R. Morante Fabricati on of nanodevices based on indi-vidual SnO2 nanowires and their electrical characterizati on In: Metal Oxide Nanostructures and Their Ap-plicati ons, A. Umar Ed., American Scienti fi c Publishers (Valencia): 2010, Vol. 3, pp 3-30

K. Kern, V. Royter, F. I. Corona-Strauss, M. Mariam and D. J. StraussHabituati on analysis of chirp vs. tone evoked auditory late responsesIn: Proceedings of 32nd Internati onal Annu-al Conference IEEE Engineering in Medicine and Biology Society: “Merging Medical Hu-manism and Technology” (EMBC’10), Au-gust 31-September 04, 2010, Buenos Aires <Argenti na>, (2010), pp 6825-6828

T. Kraus and H. Wolf Templated self-assembly of parti cles In: Springer Handbook of Nanotechnology (3rd Ed.), B. Bhushan Ed., Springer: Berlin [u. a.], 2010, pp 187-210

H. Andersson, A. Manuilskiy, J. Gao, H.-E. Nilsson, A. Rusu, S. Ayöz, I. Stolich-nov, S. Siitonen, M. Gulliksson, J. Siden, T. Lehnert, J. Adam, M. Veith, A. Merku-lov, Y. Damaschek, J. Steiger, M. Ceder-berg and M. KonecnyPrintable WORM and FRAM memories and their applicati onsIn: Large-area, Organic and Printed Electro-nics Conventi on - LOPE-C 2010, May 31-June 2, 2010, Frankfurt am Main, (2010), pp 8-12

C. Becker-Willinger, P. Kalmes, P. Her-beck-Engel and M. VeithMicro-patt ernable hybrid nanocomposites with tailorable mechanical and thermome-chanical properti esIn: Advanced Fabricati on Technologies for Micro/Nano Opti cs and Photonics III, Janu-ary 25, 2010, San Francisco <Calif., USA>, W. V. Schoenfeld, J. J. Wang, M. Loncar and T. J. Suleski, Eds., (2010), p 75910G

C. Becker-Willinger, S. Schmitz-Stöwe, D. Bentz and M. VeithKineti c investi gati ons on TiO2 nanoparti cles as photo initi ators for UV-polymerizati on in acrylic matrixIn: Micromachining and Microfabricati on Pro-cess Technology XV, January 26, 2010, San Francisco <Calif., USA>, M. A. Maher, J.-C. Chiao and P. J. Resnick, Eds., (2010), p 75900I

M. Busse, A. Kraegeloh, D. Stevens, C. Ca-velius, J. Retti g, E. Arzt and D. J. StraussModeling the eff ects of nanoparti cles on neuronal cells: from ionic channels to net-work dynamicsIn: Proceedings of 32nd Internati onal Annu-al Conference IEEE Engineering in Medicine and Biology Society: “Merging Medical Hu-manism and Technology” (EMBC’10), Au-gust 31-September 04, 2010, Buenos Aires <Argenti na>, (2010), pp 3816-3819

M. R. S. Castro, P. W. Oliveira and M. Veith Transparent conducti ng oxide nanofi lms: Properti es, growth and applicati ons In: Metal Oxide Nanostructures and Their Ap-plicati ons. Growth and Properti es (Part-2), A. Umar and Y.-B. Hahn Eds., American Scienti fi c Publishers (Valencia): 2010, Vol. 2, pp 415-443

F. I. Corona-Strauss, W. Delb, B. Schick and D. J. StraussA kernel-based novelty detecti on scheme for the ultra-fast detecti on of chirp evoked auditory brainstem responses

Lin, LeyuChina

Marti nez Miró, MarinaSpanien

McMeeking, Prof. Dr. RobertUSA

Mejia Trejo, Victoria LilianaMexiko

Mousavi, Sayed HadiIran

Murray, Dr. EoinIrland

Ndiaye, Dr. AmadouSenegal

Okumura, Prof. Dr. Leonardo LuizBrasilien

Paretkar, DadhichiIndien

Qin, Dr. EnweiChina

Sam, Dr. Ebru DevrimTürkei

Smail, Dr. HakimaFrankreich

Ullah, HameedPakistan

Witt mar, Dr. AlexandraRumänien

Yazdani-Assl, Dr. OmidIran

Zhao, JiahuaKanada

Zvonkina, Dr. IrinaRussland

Publikati onen / Publicati onsStand / Status: 01.04.2011

Einzelbeiträge in Sammelwerken / Publicati ons in collected editi ons

A. Alastalo, T. Matti la, J. Leppäniemi, M. Suhonen, T. Kololuoma, A. Schaller,

Publikati onen / Publicati ons

106

J Phys: Condens Matter 2010, 22, (49), 495401 [01.964 (2009)]

A. Al-Kahlout, D. F. Vieira, C. O. Avella-neda, E. R. Leite, M. A. Aegerter and A. PawlickaGelatin-based protonic electrolyte for elec-trochromic windowsIonics 2010, 16, (1), 13-19 [00.899 (2009)]

H. Arora, Z. Li, H. Sai, M. Kamperman, S. C. Warren and U. WiesnerBlock copolymer directed nanoporous met-al thin filmsMacromol Rapid Comm 2010, 31, (22), 1960-1964 [04.263 (2009)]

E. ArztEditorialAdv Eng Mater 2010, 12, (5), 333-334 [01.761 (2009)]

R. Bennewitz, K. Brörmann, P. Egberts, N. N. Gosvami, F. Hausen and C. HeldNanotribology - Fundamental studies of friction and plasticityAdv Eng Mater 2010, 12, (5), 362-367 [01.761 (2009)]

L. F. Boesel, C. Greiner, E. Arzt and A. Del CampoGecko-inspired surfaces: a path to strong and reversible dry adhesivesAdv Mater 2010, 22, (19), 2125-2137 [08.379 (2009)]

P. Born, E. Murray and T. KrausTemperature-induced particle self-assemblyJ Phys Chem Solids 2010, 71, (2), 95-99 [01.189 (2009)]

J. Chan, E. Crowell, M. Eder, G. Calder, S. Bunnewell, K. Findlay, S. Vernhettes, H. Höfte and C. LloydThe rotation of cellulose synthase trajec-tories is microtubule dependent and influ-ences the texture of epidermal cell walls in Arabidopsis hypocotylsJ Cell Sci 2010, 123, (20), 3490-3495 [06.144 (2009)]

A. Ciana, K. Meier, N. Daum, S. Gerbes, M. Veith, C.-M. Lehr and G. MinettiA dynamic ratio of the alpha+ and alpha- iso-forms of the tight junction protein ZO-1 is characteristic of Caco-2 cells and correlates with their degree of differentiationCell Biol Int 2010, 34, 669-678 [01.800 (2009)]

A. Neumeyer, M. Bukowski, M. Veith, C.-M. Lehr and N. DaumInteraction of nanoparticles and cells - cel-lular uptake and cytotoxic effects in vitroIn: Modern polymeric materials for environ-mental applications : 4th international semi-nar, December 01-03, 2010, Krakow <Po-land>, K. Pielichowski, Ed., (2010), pp 239-246

H. K. Schmid, H. Burghardt, E. Okunishi and W. MaderDefect structures in In-ZnO nanorods re-visited by aberration-corrected analytical TEM/STEMIn: 17th International Microscopy Congress (IMC17), September 19-24, 2010, Rio de Janeiro <Brazil>, G. Solorzano and W. de Souza, Eds., (2010), p M1.18

H. K. Schmid, E. Okunishi and T. OikawaStructural and elemental analysis of Fe-ZnO by spectroscopic imaging in Cs-cor-rected STEMIn: 17th International Microscopy Congress (IMC17), September 19-24, 2010, Rio de Janeiro <Brazil>, G. Solorzano and W. de Souza, Eds., (2010), p I5.22

M. Veith, O. C. Aktas, J.-S. Lee, M. Mar-tinez Miró, C. K. Akkan, K.-H. Schäfer and U. RauchBiphasic nano-materials and applications in life sciences: 1D A1/Al2O3 nanostruc-tures for improved neuron cell culturingIn: Nanostructured materials and systems : a collection of papers presented at the 8th Pacific Rim Conference on Ceramic and Glass Technology (PACRIM-8), May 31-June 05, 2009, Vancouver <Canada>, S. Mathur and M. Singh, Eds., ACerS, (2010), pp 117-121

Aufsätze in Zeitschriften mit Begutach-tungssystem (“referierte Zeitschriften”) / Articles in peer-reviewed journals

J. Adam, J. Dietz, M. Koch and M. VeithBonding of porous alumina structures with zirconia nanoparticlesMateriały Ceramiczne / Ceramic materials 2010, 62, (4), 510-515 [-]

E. Agiasofitou, M. Lazar and H. O. K. KirchnerGeneralized dynamics of moving disloca-tions in quasicrystals

B. G. Clark, D. S. Gianola, O. Kraft and C. P. FrickSize independent shape memory behavior of nickel-titaniumAdv Eng Mater 2010, 12, (8), 808-815 [01.761 (2009)]

J. K. Deuschle, E. J. De Souza, E. Arzt and S. EndersNanoindentation studies on crosslinking and curing effects of PDMSInt J Mater Res 2010, 101, (8), 1014-1023 [00.862 (2009)]

M. Eder, N. Concors, E. Arzt and I. M. WeissMicropatterned polymer surfaces and cel-lular response of DictyosteliumAdv Eng Mater 2010, 12, (5), 405-411 [01.761 (2009)]

M. Eder and U. Lütz-MeindlAnalyses and localization of pectin-like car-bohydrates in cell wall and mucilage of the green alga Netrium digitusProtoplasma 2010, 243, (1), 25-38 [01.523 (2009)]

M. Eder, U. Lütz-Meindl and I. M. WeissNon-invasive LC-PolScope imaging of bi-ominerals and cell wall anisotropy changesProtoplasma 2010, 246, (1), 49-64 [01.523 (2009)]

N. Eswara-Prasad, D. Vogt, T. Bidling-maier, A. Wanner and E. ArztLow cycle fatigue and creep-fatigue interac-tion in short fibre reinforced aluminium al-loy compositeMater Sci Tech 2010, 26, (11), 1363-1372 [00.794 (2009)]

E. Fanizza, L. Malaquin, T. Kraus, H. Wolf, M. Striccoli, N. Micali, A. Taurino, A. Agostiano and M. L. CurriPrecision patterning with luminescent na-nocrystal-functionalized beadsLangmuir 2010, 26, (17), 14294-14300 [03.898 (2009)]

T. Filleter and R. BennewitzStructural and frictional properties of gra-phene films on SiC(0001) studied by atomic force microscopyPhys Rev B 2010, 81, (15), 155412 [03.475 (2009)]

107

H. Lin, P. W. Oliveira, I. Grobelsek, A. Haetti ch and M. VeithThe synthesis of anatase TiO2 nanoparti cles by solvothermal method using ionic liquid as additi veZ Anorg Allg Chem 2010, 636, (11), 1947-1954 [01.226 (2009)]

H. Lin, P. W. Oliveira, V. Huch and M. VeithHydroxometalates from anion exchange re-acti ons of [BF4]

− based ionic liquids: Forma-ti on of [M(OH)6)]

2− (M = Ti, Zr) and [Zr(OH)5]−

Chem Mater 2010, 22, (24), 6518-6523 [05.368 (2009)]

R. M. McMeeking, L. Ma and E. ArztBi-stable adhesion of a surface with a dim-ple Adv Eng Mater 2010, 12, (5), 389-397 [01.761 (2009)]

M. Mitt mann-Frank, H. Berger, C. Pföh-ler, A. Bücker, H. Wilkens, E. Arzt, K.-P. Schmitt , G. Wennemuth, M. Hannig and A. BuchterKlinische und diagnosti sche Befunde bei Expositi on gegenüber Nanoparti keln und neuen MaterialienZbl Arbeitsmed 2010, 60, (10), 328-348 [-]

K. Moh, U. Werner, M. Koch and M. VeithSilver nanoparti cles with controlled disper-sity and their assembly into superstructuresAdv Eng Mater 2010, 12, (5), 368-373 [01.761 (2009)]

E. Murray, P. Born, A. Weber and T. KrausSynthesis of monodisperse silica nanoparti -cles dispersable in non-polar solventsAdv Eng Mater 2010, 12, (5), 374-378 [01.761 (2009)]

I. Mustaff a, C. Trenado, K. Schwerdtf e-ger and D. J. StraussDenoising of single-trial matrix representa-ti ons using 2D nonlinear diff usion fi lteringJ Neurosci Methods 2010, 185, (2), 284-292 [02.295 (2009)]

P. W. Oliveira, C. Becker-Willinger and M. H. JilaviSol-gel derived nanocomposites for opti cal applicati onsAdv Eng Mater 2010, 12, (5), 349-361 [01.761 (2009)]

M. Kamperman, E. Kroner, A. Del Cam-po, R. M. McMeeking and E. ArztFuncti onal adhesive surfaces with “gecko” eff ect: The concept of contact splitti ngAdv Eng Mater 2010, 12, (5), 335-348 [01.761 (2009)]

H. O. K. Kirchner and S. NeukirchFricti on of F-acti n knotsJ Mech Behav Biomed Mater 2010, 3, (1), 121-123 [03.176 (2009)]

R. Koppert, D. Gött el, G. Schultes and U. WernerNanoni@c: Hochempfi ndliche Funkti ons-schicht für Druck- und Kraft sensorenTech Mess TM 2010, 77, (12), 631-637 [00.321 (2009)]

T. KrausThe scale-up of material microstructuring: from scanning probes to self-assemblyMonatsh Chem 2010, 141, 1267-1272 [01.312 (2009)]

E. Kroner, R. Maboudian and E. ArztAdhesion characteristi cs of PDMS surfaces during repeated pull-off force measurementsAdv Eng Mater 2010, 12, (5), 398-404 [01.761 (2009)]

I. Laboriante, B. Bush, D. Lee, F. Liu, T.-J. K. Liu, C. Carraro and R. MaboudianInterfacial adhesion between rough surfac-es of polycrystalline silicon and its implica-ti ons for M/NEMS technologyJ Adhes Sci Technol 2010, 24, (15-16), 2545-2556 [01.175 (2009)]

A. Labuda, W. Paul, B. Pietrobon, R. B. Lennox, P. H. Grütt er and R. BennewitzHigh-resoluti on fricti on force microscopy under electrochemical controlRev Sci Instrum 2010, 81, (8), 083701 [01.521 (2009)]

T. Lehnert, P. Herbeck-Engel, J. Adam, G. Klein, T. Kololuoma and M. VeithDielectric properti es of a printed sol-gel matrix compositeAdv Eng Mater 2010, 12, (5), 379-384 [01.761 (2009)]

W.-C. Lien, N. Ferralis, C. Carraro and R. MaboudianGrowth of epitaxial 3C-SiC fi lms on Si(100) via low temperature SiC buff er layerCryst Growth Des 2010, 10, (1), 36-39 [04.162 (2009)]

C. P. Frick, B. G. Clark, A. S. Schneider, R. Maaß, S. Van Petegem and H. Van SwygenhovenOn the plasti city of small-scale nickel-ti tani-um shape memory alloysScripta Mater 2010, 62, (7), 492-495 [02.949 (2009)]

B. Girault, A. S. Schneider, C. P. Frick and E. ArztStrength eff ects in micropillars of a disper-sion strengthened superalloyAdv Eng Mater 2010, 12, (5), 385-388 [01.761 (2009)]

N. N. Gosvami, T. Filleter, P. Egberts and R. BennewitzMicroscopic fricti on studies on metal surfacesTribol Lett 2010, 39, (1), 19-24 [01.664 (2009)]

G. M. Guidoni, D. Schillo, U. Hangen, G. Castellanos, E. Arzt, R. McMeeking and R. BennewitzDiscrete contact mechanics of a fi brillar sur-face with backing layer interacti onsJ Mech Phys Solids 2010, 58, (10), 1571-1581 [03.317 (2009)]

A. Gutès, C. Carraro and R. MaboudianSilver dendrites from galvanic displacement on commercial aluminum foil as an eff ec-ti ve SERS substrateJ Am Chem Soc 2010, 132, (5), 1476-1477 [08.580 (2009)]

A. Gutès, I. Laboriante, C. Carraro and R. MaboudianPalladium nanostructures from galvanic displacement as hydrogen peroxide sensorSensor Actuat B 2010, 147, (2), 681-686 [03.083 (2009)]

J. Hoppstädter, B. Diesel, R. Zarbock, T. Breinig, D. Monz, M. Koch, A. Meyer-hans, L. Gortner, C.-M. Lehr, H. Huwer and A. K. KiemerDiff erenti al cell reacti on upon Toll-like re-ceptor 4 and 9 acti vati on in human alveolar and lung intersti ti al macrophagesResp Res 2010, 11, (9), 124 [03.127 (2009)]

M. Kamperman, L. T. J. Korley, B. Yau, K. M. Johansen, Y. L. Joo and U. WiesnerNanomanufacturing of conti nuous compos-ite nanofi bers with confi nement-induced morphologiesPolymer Chemistry 2010, 1, (7), 1001-1004 [-]

108

J Nanopart Res 2010, 12, (7), 2381-2385 [02.478 (2009)]

A. Solieman, A. H. Moharram and M. A. AegerterPatterning of nanoparticulate transparent conductive ITO films using UV light irradia-tion and UV laser beam writingAppl Surf Sci 2010, 256, (6), 1925-1929 [01.616 (2009)]

P. Steiner, E. Gnecco, T. Filleter, N. N. Gosvami, S. Maier, E. Meyer and R. BennewitzAtomic friction investigations on ordered superstructuresTribol Lett 2010, 39, (3), 321-327 [01.664 (2009)]

F. Tiefensee, C. Becker-Willinger, G. Heppe, P. Herbeck-Engel and A. JakobNanocomposite cerium oxide polymer matching layers with adjustable acoustic impedance between 4 MRayl and 7 MRaylUltrasonics 2010, 50, (3), 363-366 [01.223 (2009)]

M. Veith, O. C. Aktas, W. Metzger, D. Sossong, H. Ullah Wazir, I. Grobelsek, N. Pütz, G. Wennemuth, T. Pohlemann and M. OberringerAdhesion of fibroblasts on micro- and nano-structured surfaces prepared by chemical vapor deposition and pulsed laser treatmentBiofabrication 2010, 2, (3), 035001 [- (2009)]

M. Veith, C. Belot, V. Huch, H. Cui, L. Guyard, M. Knorr and C. WicklederSynthesis, crystal structure and physico-chemical studies of neodymium and erbi-um methoxides containing thienyl substit-uentsEur J Inorg Chem 2010, 2010, 879-889 [02.941 (2009)]

M. Veith, C. Belot, V. Huch, L. Guyard, M. Knorr, A. Khatyr and C. WicklederSyntheses, crystal structures, and phys-ico-chemical studies of sodium and po-tassium alcoholates bearing thienyl sub-stituents and their derived luminescent samarium(III) alkoxidesZ Anorg Allg Chem 2010, 636, (12), 2262–2275 [01.226 (2009)]

M. Veith, H. Caparrotti and V. HuchFormation of three new base adducts in the reaction of the aluminopolysilox-

S. J. O’Shea, N. N. Gosvami, L. T. W. Lim and W. HofbauerLiquid atomic force microscopy: Solvation forces, molecular order, and squeeze-OutJpn J Appl Phys 2010, 49, (8), 08LA01 [01.138 (2009)]

S. Pabisch, S. Puchegger, H. O. K. Kirch-ner, I. M. Weiss and H. PeterlikKeratin homogeneity in the tail feathers of Pavo cristatus and Pavo cristatus mut. albaJ Struc Biol 2010, 172, (3), 270-275 [03.673 (2009)]

J. Pan, R. Ganesan, H. Shen and S. MathurPlasma-modified SnO2 nanowires for en-hanced gas sensingJ Phys Chem C 2010, 114, (18), 8245-8250 [04.224 (2009)]

M. Quilitz, K. Steingröver and M. VeithEffect of the Ca/P ratio on the dielectric properties of nanoscaled substoichiometric hydroxyapatiteJ Mater Sci-Mater Med 2010, 21, (2), 399-405 [01.955 (2009)]

S. Ren, M. Wittmar, M. Aslan, I. Grobel-sek, M. Quilitz and M. VeithDielectric properties of composites in the CaO-CuO-TiO2 systemMateriały Ceramiczne / Ceramic materials 2010, 62, (4), 449-455 [-]

N. Reum, C. Fink-Straube, T. Klein, R. W. Hartmann, C.-M. Lehr and M. SchneiderMultilayer coating of gold nanoparticles with drug-polymer coadsorbatesLangmuir 2010, 26, (22), 16901-16908 [03.898 (2009)]

A. S. Schneider, B. G. Clark, C. P. Frick, P. A. Gruber and E. ArztEffect of pre-straining on the size effect in molybdenum pillarsPhil Mag Lett 2010, 90, (11), 841-849 [00.530 (2009)]

S. Schübbe, C. Cavelius, C. Schumann, M. Koch and A. KraegelohSTED microscopy to monitor agglomeration of silica particles inside A549 cellsAdv Eng Mater 2010, 12, (5), 417-422 [01.761 (2009)]

A. Solieman, S. Alamri and M. A. AegerterSynthesis of corundum structure ITO na-nocrystals by hydrothermal process at low pressure and low temperature

ane [Ph2SiO]8[AlO(OH)]4·4Et2O with pro-pane-1,3-diamineOrganometallics 2010, 29, (21), 5269-5273 [04.204 (2009)]

M. Veith, D. Kolano, T. Kirs and V. HuchCondensation reaction through base assis-tance within (Ph2SiO)8[AlO(OH)]4J Organomet Chem 2010, 695, 1074-1079 [02.347 (2009)]

M. Veith, A. Rammo, R. Heim and V. HuchDarstellung, Kristall- und Molekülstruktur eines zwölfgliedrigen N-,N’-Di-Lithium-cyc-losiloxazans [Me2SiOSiMe2N(Li)SiMe2O]2Z Anorg Allg Chem 2010, 636, (2), 320-324 [01.226 (2009)]

M. Veith, A. Rammo, O. Schütt and V. HuchSchrittweise Darstellung von verzweigten tripodalen Chlor-Methyl-Siloxanen der all-gemeinen Formel tBuSiOSiMe2yOSiMe3-

xCl3 [x = 0-3; y = 0-2] sowie Synthese der Sila-nole tBuSi[(OSiMe2)xOH]3 [x = 1, 2] und des bicyclischen Siloxans tBuSi(OSiMe2O)3SitBuZ Anorg Allg Chem 2010, 636, (7), 1212-1221 [01.226 (2009)]

I. M. WeissJewels in the pearlChemBioChem 2010, 11, (3), 297-300 [03.824 (2009)]

I. M. Weiss and H. O. K. KirchnerQuill embroidery: A case study in the me-chanics of biological materialsAdv Eng Mater 2010, 12, (5), 412-416 [01.761 (2009)]

I. M. Weiss and H. O. K. KirchnerThe peacock‘s train (Pavo cristatus and Pavo cristatus mut. alba) I. structure, mechanics, and chemistry of the tail feather covertsJ Exp Zool A 2010, 313 A, (10), 690-703 [01.444 (2009)]

E. Wohlfart, J. P. Fernandez-Blazquez, E. Knoche, A. Bello, E. Perez, E. Arzt and A. del CampoNanofibrillar patterns by plasma etching: The influence of polymer crystallinity and orientation in surface morphologyMacromolecules 2010, 43, (23), 9908-9917 [04.539 (2009)]

M. S. Wu and H. O. K. KirchnerNonlinear elasticity modeling of biogelsJ Mech Phys Solids 2010, 58, (3), 300-310 [03.317 (2009)]

109

Arbeits- und Diskussionspapiere /Technical Papers

C. Becker-Willinger, D. Bentz, S. Schmitz-Stöwe and M. VeithNANOCURE - neue Härtungsverfahren für Druckfarben, Klebstoff e und Lacke : Teilvor-haben: Synthese nanoparti kulärer oberfl ä-chenmodifi zierter Metalloxidparti kelBerichtszeitraum: 01.10.2006 - 30.09.2009, Förderkennzeichen BMBF 13N9119Abschlussbericht, 2010, Saarbrücken, 36 S.

P. RoginFunkti onsschichten für fl exible, kosten-günsti ge CIGS-Dünnschichtsolarzellen, Ak-ronym: FlexNet : Schlussbericht (öff entli-cher Teil) des VerbundvorhabensLaufzeit: 01.08.2006 - 31.01.2010, Förder-kennzeichen BMBF 03SF0321BSchlussbericht, 2010, Saarbrücken, 9 S.

M. Veith, M. Witt mar and C. HahnCorrosion protecti on by nanostructured materials - a big step forward in the indus-trial usage of these materials - EU project MULTIPROTECT has been successfully fi n-ished : publishable executi ve summaryLaufzeit: 01.03.2005 - 28.02.2009, Contract N° NMP3-CT-2005-011783 (FP 6)Executi ve Summary, 2010, Saarbrücken, 20 S.

Herausgeberschaft / Publisher

E. Arzt Advanced Engineering Materials - Special Issue Vol. 12, Iss. 5, 2010 2010, S. 327-422

Poster / Posters

C. K. Akkan, O. C. Aktas, J.-S. Lee, M. Marti nez Miró and M. VeithMicro-nano structuring to improve surface wett ability for cell culturing6th Nanoscience & Nanotechnology Confe-rence (NanoTR-VI), June 15-18, 2010, Izmir <Turkey>, p 501

E. Kroner, M. Kamperman and E. Arzt Bioinspirierte Haft systeme - von der For-schung in die Technik Magazin Forschung / Universität des Saar-landes 2010, (1), 38-45

E. Murray and T. KrausOrganosilicate nanoparti cles - a familiar material in new shapeAnnual Report, Jahresbericht 2009 - INM Leibniz-Insti tut für Neue Materialien 2010, 35-39 [-]

M. Quilitz, C. Becker-Willinger and M. Veith Chemische Nanotechnologie für die Ver-besserung industrieller Prozesse intelligenter produzieren 2010, (3), 12-13

S. Schmitz-Stöwe, C. Becker-Willinger, D. Bentz, B. Abt and M. VeithKineti c investi gati ons on TiO2 nanoparti cles as photo initi ators for UV-polymerizati on in acrylic matricesAnnual Report, Jahresbericht 2009 - INM Leibniz-Insti tut für Neue Materialien 2010, 11-17 [-]

A. S. Schneider and E. ArztSize dependent strength of bcc metal mi-cropillars: towards high strength surfaces by micropatt erningAnnual Report, Jahresbericht 2009 - INM Leibniz-Insti tut für Neue Materialien 2010, 23-27 [-]

M. Schubert and M. Veith Nanotechnologie vom Dach bis zur Terrasse nano Technologie aktuell 2010, 64, (04), 34-38

C. Schumann, C. Cavelius, S. Schübbe and A. KraegelohSti mulated emission depleti on microscopy for imaging of engineered and biological nanostructuresAnnual Report, Jahresbericht 2009 - INM Leibniz-Insti tut für Neue Materialien 2010, 44-50 [-]

M. Veith, M. Bender, C. Bubel and O. C. AktasSingle source precursors for piezoelectric and opti cal coati ngsAnnual Report, Jahresbericht 2009 - INM Leibniz-Insti tut für Neue Materialien 2010, 40-43 [-]

D. Zahn and H. TlatlikAtomisti c in situ investi gati on of the morpho-genesis of grains during pressure-induced phase transiti ons: Molecular dynamics sim-ulati ons of the B1-B2 transformati on of RbClChem Eur J 2010, 16, 13385-13389 [05.382 (2009)]

Aufsätze in übrigen Zeitschrift en /Arti cles in other journals

M. Aslan, M. Witt mar, H. Bolz and M. VeithA new approach for a slurry based coati ng system for the preventi on of high-tempera-ture oxidati onAnnual Report, Jahresbericht 2009 - INM Leibniz-Insti tut für Neue Materialien 2010, 18-22 [-]

C. Becker-Willinger, P. Kalmes and M. Veith New routes to cleanliness. Nanocomposite coati ngs off er advantages over PTFE in food producti on European Coati ngs Journal 2010, (1), 37-45

R. BennewitzNanotribologie auf Kupfer: Reibung und Verschleiß auf atomarer SkalaMetall 2010, 64, (11), 535-537 [-]

P. Egberts and R. BennewitzThe role of plasti c deformati on in nanome-ter-scale wearAdvances in Science and Technology 2010, 64, 25-32 [-]

G. Guidoni, D. Schillo, U. Hangen, G. Castellanos, E. Arzt, R. M. McMeeking and R. BennewitzThe role of the backing layer in the mechan-ical properti es of micrometer-scale fi brillar structuresAnnual Report, Jahresbericht 2009 - INM Leibniz-Insti tut für Neue Materialien 2010, 28-34 [-]

E. Kroner and E. ArztKleben ohne Klebstoff . Warum der Gecko an der Decke haft etPdN-ChiS 2010, 59, (3), 18-20 [-]

E. Kroner, M. Kamperman and E. ArztGeckoinspirierte Klebstoff e: Auf dem Weg in die industrielle AnwendungAdhäsion 2010, (9), 46-50 [-]

110

C. Cavelius, C. Schumann, S. Schübbe, M. Koch, M. Kucki, A.-R. Jochem and A. KraegelohSynthesis and modification of Atto647N-la-belled monodisperse silver, gold and silica nanoparticles for high-resolution STED mi-croscopyNanoMed - 7th International Conference on Biomedical Applications of Nanotechnolo-gy, December 02-03, 2010, Berlin

P. Egberts and R. BennewitzPlasticity in single asperity wearFANAS 2010 Conference on Friction and Ad-hesion in Nanomechanical Systems, Octo-ber 25-28, 2010, Saarbrücken, p 40

P. Egberts and R. BennewitzDiscrete creep through dislocation nucleationGordon Research Conference on Thin Film and Small-Scale Mechanical Behavior, Colby College, July 25-30, 2010, Waterville <ME, USA>

P. Egberts and R. BennewitzExamination of wear scars with multimode atomic force microscopyInternational Workshop on Advanced Ato-mic Force Microscopy Techniques. Karlsru-he Institute of Technology, March 01-02, 2010, Karlsruhe

P. Egberts and R. BennewitzCreep with single dislocation resolutionNanobrücken - Nanomechanical Testing Workshop and Hysitron User Meeting, Fe-bruary 25-26, 2010, Saarbrücken

C. Fink-StraubeCentral Service Facility: Chemical AnalyticsINM-Industrietag 2010, November 23, 2010, Saarbrücken

B. Girault, A. S. Schneider, C. P. Frick and E. ArztStrength-independence of oxide dispersi-on strengthened materials with micropillar diameterNanobrücken - Nanomechanical Testing Workshop and Hysitron User Meeting, Fe-bruary 25-26, 2010, Saarbrücken

G. Guidoni, D. Schillo, U. Hangen, G. Castellanos, E. Arzt, R. M. McMeeking and R. BennewitzDo the individual pillars of a structured compliant surface communicate with each other?CAMTEC II, Symposium on Fine-Scale Me-chanical Characterisation and Behaviour,

O. C. AktasProgram Division: CVD / BiosurfacesINM-Industrietag 2010, November 23, 2010, Saarbrücken

O. C. Aktas, W. Metzger, M. Martinez Miró, B. Schwab, L. Schimmelpfennig, H. Smail, J.-S. Lee, M. Oberringer, T. Pohlemann and M. VeithSelective adhesion of human osteoblasts and human fibroblasts on 1D Al/Al2O3-na-nostructuresEuropean Orthopaedics Research Society (EORS), Swiss 2010, June 30-July 02, 2010, Davos <Switzerland>

E. ArztProgram Division: Functional SurfacesINM-Industrietag 2010, November 23, 2010, Saarbrücken

C. Becker-WillingerProgram Division: Nanomers®INM-Industrietag 2010, November 23, 2010, Saarbrücken

R. BennewitzProgram Division: NanotribologyINM-Industrietag 2010, November 23, 2010, Saarbrücken

R. Bennewitz, T. Filleter, C. Held, N. N. Gosvami, F. Hausen and A. LabudaMolecular films as lubricantsGordon Research Conference on Tribology, Colby College, June 27-July 02, 2010, Wa-terville <ME, USA>

K. Brörmann and R. BennewitzFriction of microstructured rubber surfacesFANAS 2010 Conference on Friction and Adhesion in Nanomechanical Systems, Oc-tober 25-28, 2010, Saarbrücken, pp 35-36

K. Brörmann and R. BennewitzExperimental observation of the deformati-on of microstructured rubber surfaces prior to and during slidingCECAM Workshop on “Stick-slip dyna-mics, from nano to geophysical scales”, CE-CAM-HQ-EPFL, May 03-05, 2010, Lausanne <Schwitzerland>

G. Castellanos, M. Kamperman and E. ArztInfluence of stiffness on adhesive proper-ties for epoxy resin composites - from bulk to fibrillar surfacesFANAS 2010 Conference on Friction and Ad-hesion in Nanomechanical Systems, Octo-ber 25-28, 2010, Saarbrücken, p 37

Downing College, March 29-30, 2010, Cam-bridge <UK> Best Poster Award, 2nd Place

F. Hausen and R. BennewitzElectrochemical control of atomic frictionFANAS 2010 Conference on Friction and Ad-hesion in Nanomechanical Systems, Octo-ber 25-28, 2010, Saarbrücken, p 45

C. Held, T. Seyller and R. BennewitzVelocity dependent friction on graphene/SiC(0001)FANAS 2010 Conference on Friction and Ad-hesion in Nanomechanical Systems, Octo-ber 25-28, 2010, Saarbrücken, p 46

S. Heusing, M. Quilitz and P. W. OliveiraImprovement of the conductivity of wet chemical deposited ITO coatings by enhan-cement of matrix conductivity3rd International Symposium on Transpa-rent Conductive Materials, TCM 2010, Oc-tober 17-21, 2010, Analipsi/Hersonissos <Crete, Greece>

M. H. Jilavi, C. Faller-Schneider, C. Wühr, S.-G. Kim and P. W. OliveiraDevelopment of single layer antireflective coating via sol gel method for solar cell with photocathalytic effect6. Thüringer Grenz- und Oberflächentage, September 07-08, 2010, Gera, pp 232-234

J. S. Kaiser, M. Kamperman, B. Schick and E. ArztEnhanced adhesion of biodegradable and biocompatible gecko-inspired micropatter-ned surfacesNanoMed - 7th International Conference on Biomedical Applications of Nanotechnolo-gy, December 02-03, 2010, Berlin

M. Koch, S. Kiefer, C. Cavelius and A. KraegelohThe effects of Ag0 nanoparticles on human cells: a mechanistic investigation8th International Conference and Workshop on Biological Barriers - in vitro Tools, Nano-toxicology, and Nanomedicine, Universität des Saarlandes, March 21-April 01, 2010, Saarbrücken

A. KraegelohJunior Research Group: Nano Cell Interac-tionsINM-Industrietag 2010, November 23, 2010, Saarbrücken

111

S. Pabisch, S. Puchegger, H. O. K. Kirch-ner, I. M. Weiss and H. PeterlikLocal structure of peacock feathers during growth - an X-ray diff racti on studyCOST Strategic Workshop on Bio-inspired Materials, April 13-15, 2010, Wien, p 155

B. ReinhardProgram Division: NanoprotectINM-Industrietag 2010, November 23, 2010, Saarbrücken

N. Reum, C. Fink-Straube and M. SchneiderMulti layer coati ng of gold nanoparti cles with drug-polymer coadsorbate37th Annual Meeti ng and Expositi on of the Controlled Release Society, July 13, 2010, Portland <OR, USA>

E. D. Sam, D. Paretkar, M. Kamperman, P. W. Oliveira and E. ArztA simple method for replicati on of micro-pillars through fl uoropolymer moldingTopical workshop - Bioinspired adhesion: from geckos to new products?, July 07-09, 2010, Saarbrücken

L. Schimmelpfennig, B. Schwab, W. Metzger, D. Sossong, O. C. Aktas, M. Marti nez Miró, J.-S. Lee, M. Veith, T. Pohlemann and M. OberringerCell compati bility of micro- and nanostruc-tured alumina surfaces prepared by chemi-cal vapor depositi onBioStar 2010 - Science in Exchange : 4th Con-gress on Regenerati ve Biology and Medici-ne, October 13-15, 2010, Stutt gart

H. K. SchmidCentral Service Facility: Physical Analyti csINM-Industrietag 2010, November 23, 2010, Saarbrücken

H. K. Schmid, H. Burghardt, E. Okunishi and W. MaderDefect structures in In-ZnO nanorods re-visited by aberrati on-corrected analyti cal TEM/STEM17th Internati onal Microscopy Congress (IMC17), September 19-24, 2010, Rio de Janeiro <Brazil>

D. Marchett o, C. Held, F. Hausen, M. Di-enwiebel and R. BennewitzSliding on graphene at the micro-scaleFANAS 2010 Conference on Fricti on and Ad-hesion in Nanomechanical Systems, Octo-ber 25-28, 2010, Saarbrücken, p 50

D. Marchett o, C. Held, F. Hausen, M. Di-enwiebel and R. BennewitzMicro-scale fricti on of grapheneGordon Research Conference on Tribology, Colby College, June 27-July 02, 2010, Wa-terville <ME, USA>

M. Marti nez Miró, B. Schwab, L. Schim-melpfennig, J.-S. Lee, W. Metzger, M. Oberringer, G. Wennemuth, T. Pohle-mann, O. C. Aktas and M. VeithDiverse response of human osteoblasts and normal human dermal fi broblasts on Al/Al2O3 composite nanowiresNanoMed - 7th Internati onal Conference on Biomedical Applicati ons of Nanotechnolo-gy, December 02-03, 2010, Berlin

M. Mitt mann-Frank, H. Berger, A. Krae-geloh, M. Hannig, G. Wennemuth and A. BuchterTäti gkeitsparallele Diagnosti k bei berufl i-cher Expositi on gegenüber Nanoparti keln und neuen Materialien50. Jahrestagung Deutsche Gesellschaft für Arbeitsmedizin und Umweltmedizin 2010, June 16-19, 2010, Dortmund

M. Mitt mann-Frank, H. Berger, A. Krae-geloh, C. Pföhler, A. Bücker, H. Wilkens and A. BuchterAnalysis of clinical and diagnosti c fi ndings dur-ing exposures in chemical nanotechnologyNanotechnologie-Tagung der nanotech-da-ta.com, University Paul Verlaine, November 25, 2010, Metz <France>

M. Mitt mann-Frank, H. Berger, A. Krae-geloh, G. Wennemuth and A. BuchterExposures in chemical nanotechnologyNanotechnologie-Tagung der nanotech-da-ta.com, University Paul Verlaine, November 25, 2010, Metz <France>

P. W. OliveiraProgram Division: Opti cal MaterialsINM-Industrietag 2010, November 23, 2010, Saarbrücken

A. Kraegeloh, C. Brochhausen, R. Dan-zebrink, A. K. Kiemer, M. W. Laschke, L. Santen, G. Schneider, R. Stauber and R. HanselmannNanoKon - novel nanoscaled contrast agents and systemati c evaluati on of their safetyNanoMed - 7th Internati onal Conference on Biomedical Applicati ons of Nanotechnolo-gy, December 02-03, 2010, Berlin

A. Kraegeloh, S. Kiefer, C. Cavelius and M. KochMechanisti c insights into the eff ects of Ag0 nanoparti cles and silver ions on human cellsNanotoxicology, June 02-04, 2010, Edin-burgh <UK>

T. KrausJunior Research Group: Structure formati on at small scalesINM-Industrietag 2010, November 23, 2010, Saarbrücken

E. KronerAdhesion measurements on structured surfaces using fl at probes with controlled alignmentWorkshop „Bioinspired adhesion: from ge-ckos to new products?“, July 07-10, 2010, Saarbrücken Best Poster Award, 2nd Place

E. Kroner and E. ArztAdhesion measurements with controlled alingmentFANAS 2010 Conference on Fricti on and Ad-hesion in Nanomechanical Systems, Octo-ber 25-28, 2010, Saarbrücken, p 48Excellent Poster Award

T. Lehnert, J. Adam, P. Herbeck-Engel, R. Drumm and M. VeithLow temperature processable dielectric fi lms for printed electronics applicati onsMaterials Science and Engineering, August 24-26, 2010, Darmstadt

M. Lessel, P. Loskill, K. Jacobs, N. N. Gosvami and R. BennewitzAFM fricti on studies on composite subst-rates: New insights on the role of van der Waals forcesFANAS 2010 Conference on Fricti on and Ad-hesion in Nanomechanical Systems, Octo-ber 25-28, 2010, Saarbrücken, p 49

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Vorträge / Talks

FANAS 2010 Conference on Friction and Ad-hesion in Nanomechanical Systems, Octo-ber 25-28, 2010, Saarbrücken, p 59

I. M. WeissBackstage the formation of biomineralizati-on ScaffoldsGordon Research Conference “Biominera-lization”, August 14-20, 2010, New London <NH, USA>

I. M. WeissProgram Division: BiomineralizationINM-Industrietag 2010, November 23, 2010, Saarbrücken

I. M. Weiss and H. O. K. KirchnerThe Peacock‘s train: Structural and mecha-nical inspiration for plant‘s designCOST Strategic Workshop on Bio-inspired Materials, April 13-15, 2010, Wien, p 189

Vorträge / TalksStand / Status: 01.04.2011

Eingeladene Vorträge / Invited Talks

J. Adam, A. Alastalo and S. SiitonenInformationsspeicher gedruckt auf Papier - Technologien und Anwendungen Seminar der Papiertechnischen Stiftung (PTS) NE 1036 ‘Nanotechnolgie in der Pa-pierindustrie’; April 13-14, 2010; München

J. Adam and T. LehnertSynthesis of ferroelectric metal-oxide nano-particles and ink development for R2R fab-rication PRODI Workshop and Seminar ‘Roll-to-Roll Technologies: Introduction and Topical Chal-lenges’; October 04-06, 2010; München

O. C. Aktas and J.-S. LeeMicro gravity effect and gas phase synthesis 5th CRC Exchange Meeting, AO foundation; February 19, 2010; Davos, Switzerland

O. C. Aktas and J.-S. LeeNanostructured surfaces and the influence of gravity versus non gravity on those na-nostructures 5th CRC Exchange Meeting, AO foundation; February 19, 2010; Davos, Switzerland

O. C. Aktas and M. VeithArtificial surfaces as biomaterial coatings European Conference on Nanofilms; March 22-25, 2010; Liège, Belgium

H. K. Schmid, E. Okunishi and T. OikawaStructural and elemental analysis of Fe-ZnO by spectroscopic imaging in Cs-corrected STEM17th International Microscopy Congress (IMC17), September 19-24, 2010, Rio de Janeiro <Brazil>

A. S. SchneiderJunior Research Group: Metallic Micro-structuresINM-Industrietag 2010, November 23, 2010, Saarbrücken

A. S. Schneider, B. G. Clark, C. P. Frick, P. A. Gruber and E. ArztInfluence of orientation on the size effect in BCC pillars with different critical tempe-ratureGordon Research Conference „Thin Film and Small Scale Mechanical Behavior“, July 25-30, 2010, Waterville <ME, USA>

A. S. Schneider, B. G. Clark, C. P. Frick, P. A. Gruber and E. ArztEffect of pre-straining on the size effect in molybdenum pillarsCAMTEC II, March 29-30, 2010, Cambridge <UK>

S. Schübbe, C. Schumann, C. Cavelius and A. KraegelohIntracellular localization of about 30 nm SiO2 nanoparticles in Caco-2 cells8th International Conference and Workshop on Biological Barriers - in vitro Tools, Nanotoxico-logy, and Nanomedicine, Universität des Saar-landes, March 21-April 01, 2010, Saarbrücken

S. Schübbe, C. Schumann, C. Cavelius and A. KraegelohSilica nanoparticle uptake in A549 cells: analysis by STED microscopyNanotoxicology, June 02-04, 2010, Edin-burgh <UK>

C. Schumann, C. Cavelius, S. Schübbe and A. KraegelohApplicability of image correlation methods to STED microscopyAdvanced Light Microscopy Techniques and Their Applications10th International ELMI Meeting, May 18-21, 2010, Heidelberg

H. Tlatlik, T. Staut, B. Heiland, R. Benne-witz and A. K. SchlarbTribological behavior of PEEK-based tribo-composites on small scales

O. C. AktasNanotechnologische Modifikation von Im-plantat-Oberflächen für die Verwendung in der Kinderkardiologie Fortbildung der Kinderkardiologie, Uniklinik Homburg; June 23, 2010; Homburg

O. C. AktasNanostructured surfaces by CVD Middle East Technical University; July 05, 2010; Ankara, Turkey

O. C. AktasGas phase synthesis of nanomaterials Korean University of Technology and Educa-tion; July 26, 2010; Cheonan, South Korea

O. C. AktasNanostructures by CVD Kocaeli University; July 30, 2010; Kocaeli, Turkey

O. C. AktasMicro/nanostructured surfaces for cardio-vascular stents Koranet Annual Conference - Research for life-long health; September 09, 2010; Buda-pest, Hungary

O. C. AktasNanostructured surfaces for medical appli-cations GDCh-Kurs Chemische Nanotechnologien; September 17, 2010; Saarbrücken

O. C. AktasNanostructured surfaces for medical appli-cations Christian-Albrechts-Universität; September 22, 2010; Kiel

E. ArztDas „neue“ INM Saarbrücken. Von der che-mischen Nanotechnologie zu Biomateriali-en DECHEMA; January 19, 2010; Frankfurt am Main

E. ArztGecko-Haftstrukturen: Grundlagen, Ent-wicklungsstand und Perspektiven Jubiläumskolloquium „10 Jahre Gemeinsa-me Forschung in der Klebtechnik“, DECHE-MA; February 23, 2010; Frankfurt am Main

E. Arzt and M. KampermanBioinspired adhesive surfaces COST Strategic Workshop on Principles and Development of Bio-Inspired Materials; Ap-ril 13-15, 2010; Wien, Austria

113

E. ArztFibrilläre Haft oberfl ächen vom Vorbild Na-tur zur technischen Anwendung NanoVision 2010, Karlsruher Insti tut für Technologie; December 09, 2010; Eggen-stein-Leopoldshafen

C. Becker-WillingerNeue Materialien: Was ist Nanotechnologie? 11. Jahrestreff en des Arbeitskreises Biblio-theken und Informati onseinrichtungen der Leibniz-Gemeinschaft ; September 15-17, 2010; Saarbrücken

C. Becker-WillingerNeue Oberfl ächeneigenschaft en über Na-noparti kel Hygienic Design Tage; October 05, 2010; Weihenstephan

C. Becker-WillingerChancen und Risiken der Nanotechnologie Wissenswerte Bremen, Workshop; Novem-ber 09, 2010; Bremen

C. Becker-WillingerNeue Oberfl ächenmaterialien für tribologi-sche Anwendungen INM-Industrietag 2010; November 23, 2010; Saarbrücken

C. Becker-WillingerAbrasion resistant anti -adhesive and tribolog-ical coati ngs based on Nanomer technology Sirris; November 25, 2010; Diepenbeek, Belgium

R. BennewitzFeynman’s talk, nanomachines, and fricti on force microscopy of graphene Seminar at the University of Karlsruhe; Ja-nuary 25, 2010; Karlsruhe

R. BennewitzExperimental observati on of instabiliti es in fricti on CECAM Workshop on “Sti ck-slip dynamics, from nano to geophysical scales”, CECAM-HQ-EPFL; May 03-05, 2010; Lausanne, Swit-zerland

R. BennewitzSti ck-slip phenomena from atomic fricti on to microscopic detachment waves Swisstribology Meeti ng “Science in Tribolo-gy”, ETH Zürich; May 11, 2010; Zürich, Swit-zerland

R. BennewitzAtomare Tribologie: Graphen als ultradün-ner Schmierstoff

E. ArztMikrostrukturierte Funkti onsoberfl ächen - vom Vorbild Natur zu prakti schen Anwen-dungen Münchner Physikkolloquium; May 10, 2010; München

E. ArztBioinspired reversible adhesives by micro and nanopatt erning techniques Workshop „Bioinspired adhesion: from ge-ckos to new products?“; July 07-09, 2010; Saarbrücken

E. ArztSwitchable adhesion surfaces through bio-mimeti c principles WCARP 4th World Congress on Adhesion & Related Phenomena 2010; September 27-30, 2010; Arcachon, France

E. ArztSwitchable adhesion surfaces through fi b-rillar microstructure MS&T’10 - Materials Science and Technolo-gy 2010 Conference; October 17-21, 2010; Houston, TX, USA

E. ArztStrength, adhesion, sound and survival: a tour of size eff ects John Dorn Lecture, Northwestern Universi-ty; October 26, 2010; Chicago, Ill., USA

E. Arzt, D. Paretkar and E. KronerMikrostrukturierte Haft oberfl ächen - Vom Vorbild Natur zu prakti schen Anwendungen Infotag „Von der Natur lernen“, Dechema; November 15, 2010; Frankfurt am Main

E. ArztNanomaterials - a route from chemistry and physics to biology Deutsch-Brasilianisches Wissenschaft sjahr - gemeinsame Seminarreihe Brasilianischen Akademie der Wissenschaft en/Leopoldina -Nati onale Akademie der Wissenschaft en, Rio de Janeiro / Sao Paulo; November 15-19, 2010; Sao Paulo/Rio de Janeiro, Brazil

E. ArztStrukturierte Oberfl ächen: neue Adhäsi-onskonzepte für Technik und Medizin INM-Industrietag 2010; November 23, 2010; Saarbrücken

E. ArztInnovati on in der Werkstofft echnik für Na-no-Werkstoff e Impulsreferat, Innovati onstag Dillinger Hüt-te; December 09, 2010; Dillingen

Eröff nung des MikroTribologie Centrums µTC Karlsruhe; May 11-12, 2010; Karlsruhe

R. BennewitzAtomic fricti on - from UHV to the electro-chemical cell Bunsentagung 2010, Universität Bielefeld; May 13-15, 2010; Bielefeld

R. BennewitzConnecti ng fricti on to atomic structure Gordon Research Conference on Tribolo-gy, Colby College; June 27-July 02, 2010; Waterville, ME, USA

R. BennewitzSti ck-slip fricti on from atoms to microsco-pic structures Seminar of Physics Dept., McGill Universi-ty; July 22, 2010; Montreal, Canada

R. BennewitzFricti on on molecularly thin fi lms Gordon Research Conference on Thin Film and Small-Scale Mechanical Behavior, Colby College; July 25-30, 2010; Waterville, ME, USA

R. BennewitzPlasti zität, Oberfl ächenstabilität auf Na-noskala von Kupfer HochschulKupferSymposium, Universi-tät des Saarlandes; November 11, 2010; Saarbrücken

A. Demir, E. Akman, B. Gerc and O. C. AktasNanoparti cle synthesis by femtosecond laser irradati on Opti c, Electro-Opti c and Photonics Work-shop, Istanbul Technical University; Sep-tember 08, 2010; Istanbul, Turkey

M. KampermanReversible adhesion of gecko-inspired sur-faces FANAS Workshop on “Understanding Ad-hesion: from Nature to man-made de-vices”; May 11, 2010; Alberobello, Italy

M. KampermanDesign, synthesis and characterizati on of arti fi cial bioinspired adhesives S.C.A.N 2010 Synthesis, Characterizati on, and Applicati ons of Nanomaterials, Work-shop and School, Bilkent University; Septem-ber 30-October 06, 2010; Ankara, Turkey

114

P. W. OliveiraMaterial and coatings Workshop mit Kocaeli Universität; June 30, 2010; Istanbul, Turkey

P. W. OliveiraFrom idea to product Inovatec - 6th Technological Innovation Exhi-bition, Expominas; October 07, 2010; Belo Horizonte, Brazil

P. W. OliveiraMaterialien für die druckbare ElektronikINM-Industrietag 2010; November 23, 2010; Saarbrücken

M. Quilitz, K.-P. Schmitt and J. AdamHerstellung keramischer Nanopartikel über Verfahren der Chemischen Nanotechnologie GDCh-Kurs “Chemische Nanotechnologien und Anwendungen in Technik und Medi-zin”; September 16, 2010; Saarbrücken

M. Quilitz, S. Schmitz-Stöwe and C. Be-cker-WillingerNanokomposite aus nanoskaligen, oxi-dischen Partikeln und polymerartigen Ma-trizes GDCh-Kurs „Chemische Nanotechnologien und Anwendungen in Technik und Medi-zin“; September 17, 2010; Saarbrücken

M. Quilitz, S. Heusing and P. W. OliveiraCurrent in invisible conductors - Material development for transparent, conductive oxide coatings (TCO) Inovatec - 6th Technological Innovation Ex-hibition; October 07, 2010; Belo Horizonte, Brazil

R. Rolles and M. QuilitzINM - New materials: From idea to innova-tion Korea-EU High level networking Workshop, KIST Europe; October 25, 2010; Saarbrücken

A. K. Schlarb, I. J. Zvonkina, L. Prado and K. SchultePerformance of CNT-reinforced epoxy re-sins in tribological applications Hong Kong University of Science and Tech-nology; September 22, 2010; Hong Kong

A. K. SchlarbProspects of plastics technology due to re-inforcement on nano- and microscale IUMRS-ICA 2010 11th International Con-ference in Asia; September 25-28, 2010; Qingdao, China

H. O. K. KirchnerAre natural materials better than man made ones? COST Strategic Workshop on Principles and Development of Bio-inspired Materials; Ap-ril 13-15, 2010; Wien, Austria

A. KraegelohInteraktion von Nanopartikeln mit huma-nen Zellen Kolloquium des Instituts für Mikrobiologie und Biotechnologie, Universität Bonn; Feb-ruary 05, 2010; Bonn

A. KraegelohSTED microscopy to monitor nano cell inter-actions Saarland Microscopy Workshop, Saarland University; March 10, 2010; Homburg

A. KraegelohNano-Sicherheit INM-Industrietag 2010; November 23, 2010; Saarbrücken

A. KraegelohInteraction of nanoparticles with human cells: analysis by STED-microscopy Nanotechnologie-Tagung der nanotech-da-ta.com, University Paul Verlaine; November 25, 2010; Metz, France

A. Neumeyer, M. Bukowski, M. Veith, C.-M. Lehr and N. DaumInteraction of nanoparticles and cells - cel-lular uptake and cytotoxic effects in vitro Modern polymeric materials for environ-mental applications: 4th international semi-nar; December 01-03, 2010; Krakow, Poland

P. W. OliveiraNanomaterials for optics UK-German Partnering Workshop; March 03, 2010; Karlsruhe

P. W. OliveiraNanoparticles for optical application Saudi Science Conference; March 22, 2010; Madinah, Saudi Arabia

P. W. OliveiraZusammenarbeit mit Brasilien BMBF Roundtable Lateinamerika; May 10, 2010; Bonn

P. W. OliveiraTechnologietransfer 27. Workshop Deutsch-Brasilianische WTZ Kommissionssitzung; May 31, 2010; Mün-chen

A. K. SchlarbProspects of plastics technology due to re-inforcement and efficient manufacturing Key Laboratory of Rubber-plastics, Ministry of Education China, Qingdao University of Science and Technology, Prof. Shugao Zhao; September 26, 2010; Qingdao, China

A. K. SchlarbVerstärkte Kunststoffe - Problemlöser für die Automobilindustrie? Automobil-Cluster; October 06, 2010; Linz, Austria

A. K. SchlarbVom Filament zum Bauteil Forum Composite Technology, VDMA; De-cember 15, 2010; Frankfurt am Main

A. S. Schneider, B. G. Clark, C. P. Frick, P. A. Gruber and E. ArztCorrelation between critical temperature and strength of small-scale bcc pillars Karlsruhe Institute of Technology KIT, Prof. Gumbsch; October 2010; Karlsruhe

D. J. StraussOn the multiscale analysis of evoked poten-tials IEEE Satellite Symposium on Emerging Tech-nologies in Biomedicine; April 04, 2010; An-talya, Turkey

D. J. StraussMultiscale modeling in auditory processing & perception US-Turkey Advanced Institute on Global Healthcare Challenges, Reverse Engineering the Brain; July 21, 2010; Antalya, Turkey

M. VeithSurface et matériau: un lien indissociable! La Pépinière d’Entreprises EURODEV CEN-TER et l’Association Art’Ladies Culture et Fantaisie; January 27, 2010; Forbach, France

M. VeithFrom molecules to material Indian Institute of Technology Kanpur (IIT Kanpur); February 03, 2010; Kanpur, India

M. VeithFrom molecules to material Panjab University Chandigarh; February 05, 2010; Chandigarh, India

115

E. Arzt and E. KronerWas hält den Gecko an der Decke? Neue Materialkonzepte aus der Biologie Tag der Off enen Tür der Universität des Saarlandes; June 26, 2010; Saarbrücken

C. Becker-WillingerNanocomposites CuVito; November 15, 2010; Cambridge, UK

C. Bernarding, F. I. Corona-Strauss, M. Latzel and D. J. StraussAuditory streaming and listening eff ort: an event related potenti al study 32nd Internati onal Annual Conference IEEE Engineering in Medicine and Biology Socie-ty: “Merging Medical Humanism and Tech-nology” (EMBC’10); August 31-September 04, 2010; Buenos Aires, Argenti na

C. Bernarding, D. J. Strauss, M. Latzel and F. I. Corona-StraussNon-listening eff ort related parameters in auditory discriminati on paradigms 32nd Internati onal Annual Conference IEEE Engineering in Medicine and Biology Socie-ty: “Merging Medical Humanism and Tech-nology” (EMBC’10); August 31-September 04, 2010; Buenos Aires, Argenti na

P. Born, J. Lacava and T. KrausMesoscopic self-assembly of colloidal na-noparti cle suspensions into superstructu-res MRS Spring Meeti ng; April 05-09, 2010; San Francisco, Calif., USA

K. Brörmann and R. BennewitzFricti on induced deformati on of microstruc-tured rubber surfaces DPG Spring Meeti ng; March 21-26, 2010; Regensburg

M. Busse, A. Kraegeloh, D. Stevens, C. Cavelius, J. Retti g, E. Arzt and D. J. StraussModeling the eff ects of nanoparti cles on neuronal cells: from ionic channels to net-work dynamics 32nd Internati onal Annual Conference IEEE Engineering in Medicine and Biology Socie-ty: “Merging Medical Humanism and Tech-nology” (EMBC’10); August 31-September 04, 2010; Buenos Aires, Argenti na

DPG Frühjahrstagung; March 21-26, 2010; Regensburg

I. M. WeissBiominerals: Documents for the story of life on earth Human Document Project - KIST Korea Ins-ti tute of Science and Technology; June 30, 2010; Saarbrücken

I. M. WeissOn mineralized and non-mineralized biolog-ical materials: Pearls and Peacock’s feathers Max-Planck-Insti tut für Kolloid- und Grenz-fl ächenforschung; September 23, 2010; Potsdam

Sonsti ge Vorträge / Other talks

J. AdamWP2-Materials. Synthesis and characterisa-ti on of ferroelectric nanoparti cles and pas-tes. Parti culate FRAM cells 3rd PriMeBits Review Meeti ng; February 23, 2010; Espoo, Finland

J. Adam, T. Lehnert, R. Drumm, G. Klein, P. Herbeck-Engel and M. VeithDielektrische und ferroelektrische Eigen-schaft en von druckbaren ungesinterten Schichten auf der Basis von BaTiO3-Parti keln Jahrestagung der Deutschen Keramischen Ge-sellschaft (DKG) / Symposium Hochleistungs-keramik 2010; March 22-24, 2010; Hermsdorf

O. C. Aktas, C. K. Akkan, J.-S. Lee, M. Marti nez Miró and M. VeithLarge broad absorpti on of Al/Al2O3 core-shell nanowires E-MRS 2010 Spring Meeti ng; June 07-11, 2010; Strasbourg, France

O. C. Aktas, J.-S. Lee, U. Rauch, H. Smail, K.-H. Schäfer and M. VeithAdhesion and proliferati on of neuron cells on bi-phasic nanowires E-MRS 2010 Spring Meeti ng; June 07-11, 2010; Strasbourg, France

O. C. Aktas, E. Dörrschuk, M. Marti nez Miró, C. Schuh, H. Smail, J.-S. Lee, C. K. Akkan, M. Veith and H. Abdul-KhaliqInteracti on of endothelial and smooth mu-scle cells with nanostructured surfaces: Fu-ture stent concepts NanoMed - 7th Internati onal Conference on Biomedical Applicati ons of Nanotechnolo-gy; December 02-03, 2010; Berlin

M. VeithFrom molecules to material Indian Insti tute of Technology Bombay (IIT Bombay); February 08, 2010; Mumbai, India

M. VeithFrom molecules to material University of Hyderabad; February 09, 2010; Hyderabad, India

M. VeithFrom molecules to material Indian Insti tute of Technology Madras (IIT Madras); February 11, 2010; Chennai, India

M. VeithNano-scaled materials for corrosion protecti on Surfair; June 10-11, 2010; Biarritz, France

M. VeithFrom molecules to functi onal materials Workshop Universität Kocaeli; June 29-July 01, 2010; Kocaeli, Turkey

M. VeithMolekülchemische Vorstufen für medizi-nisch relevante Materialien GDCh-Vortrag Uni Regensburg; July 06, 2010; Regensburg

M. Veith and M. QuilitzChemische Nanotechnologie - Grundlagen GDCh-Kurs “Chemische Nanotechnologien und Anwendungen in Technik und Medi-zin”; September 16-17, 2010; Saarbrücken

M. VeithSurfaces with Al2O3 structures Nanomat-Workshop; October 06, 2010; Darmstadt

M. VeithKeramische Nanoparti kel im Baubereich für besondere Beanspruchungen 2. Symposium “Beschichten von Beton”, TAW; October 26, 2010; Bochum

M. Veith, O. C. Aktas, J.-S. Lee, M. Mar-ti nez Miró, K.-H. Schäfer, W. Metzger, M. Oberringer and T. PohlemannNew results concerning cell selecti on with arti fi cial nano- and micro-structured sur-faces NanoMed - 7th Internati onal Conference on Biomedical Applicati ons of Nanotechno-logy; December 02-03, 2010; Berlin

I. M. Weiss and H. O. K. KirchnerPearls and feathers: New concepts and in-spirati on for plant‘s design

116

DPG Spring Meeting; March 21-26, 2010; Regensburg

F. Hausen and R. BennewitzElectrochemical control of atomic friction 61st Annual Meeting of the ISE (Int. Socie-ty of Electrochemistry); September 26-Oc-tober 01, 2010; Nice, France

B. Heiland, A. S. Schneider, E. Arzt and I. M. WeissSkalenübergreifende Strukturanalyse an Anschliffen und Dünnschliffen von Seeohr-Schalen Fortschritte in der Metallographie - 13. In-ternationale Metallographie-Tagung an der Montanuniversität Leoben; September 29-October 01, 2010; Leoben, Austria

C. Held and R. BennewitzFriction on graphene/SiC(0001) DPG Spring Meeting; March 21-26, 2010; Regensburg

S. Heusing, M. Quilitz and P. W. OliveiraImprovement of the conductivity of wet chemical deposited ITO coatings by enhan-cement of the matrix conductivity 3rd International Symposium on Transparent Conductive Materials, TCM 2010; October 17-21, 2010; Hersonnissos, Crete, Greece

M. KampermanBioinspired structured surfaces for enhan-ced actuated adhesion Dutch Polymer Days; February 15, 2010; Veldhoven, Netherlands

M. KampermanBioinspired adhesive systems Werkgroep Vloeistoffen en Grensvlakken; February 16, 2010; Veldhoven, Netherlands

M. Kamperman, L. T. J. Korley, Y. L. Joo and U. WiesnerContinuous composite nanofibers with con-finement-induced morphologies MRS Spring Meeting 2010; April 05-09, 2010; San Francisco, Calif., USA

M. Kamperman, D. Paretkar and E. ArztBioinspired patterned surfaces with actua-ted adhesion MRS Spring Meeting 2010; April 05-09, 2010; San Francisco, Calif., USA

M. Kamperman, R. S. Yelamanchili, T. Lunkenbein, Z. Li, J. Breu and U. WiesnerHexagonally ordered mesoporous Keggin-type polyoxometalates

F. I. Corona-Strauss, W. Delb, B. Schick and D. J. StraussA kernel-based novelty detection scheme for the ultra-fast detection of chirp evoked auditory brainstem responses 32nd International Annual Conference IEEE Engineering in Medicine and Biology Socie-ty: “Merging Medical Humanism and Tech-nology” (EMBC’10); August 31-September 04, 2010; Buenos Aires, Argentina

A. Demir, M. Oberringer, E. Akman, O. C. Aktas, H. Abdul-Khaliq and M. VeithFemtosecond laser structuring of surfaces for controlled adhesion and proliferation of endothelial cells E-MRS 2010 Spring Meeting; June 07-11, 2010; Strasbourg, France

M. EderNon-invasive LC-PolScope imaging of cell walls and their comparison to biominerals The XII Cell Wall Meeting; July 25-30, 2010; Porto, Portugal

M. EderResponse of Dictyostelium discoideum to micropatterned materials Annual International Dictyostelium Confe-rence; August 01-06, 2010; Cardiff, UK

P. Egberts and R. BennewitzCreep with single dislocation resolution DPG Spring Meeting; March 21-26, 2010; Regensburg

N. N. GosvamiMicroscopic friction on metal surfaces International Workshop on Advanced Ato-mic Force Microscopy Techniques. Karlsru-he Institute of Technology; March 01-02, 2010; Karlsruhe

N. N. Gosvami, P. Egberts and R. Ben-newitzAtomic stick-slip friction on a metal vs. a monolayer lubricant surface DPG Spring Meeting; March 21-26, 2010; Regensburg

G. GuidoniDiscrete contact mechanics of a fibrillar sur-face with backing layer interactions Nanobrücken - Nanomechanical Testing Workshop and Hysitron User Meeting; Fe-bruary 25-26, 2010; Saarbrücken

F. Hausen and R. BennewitzFrictional changes upon modification of sin-gle crystal electrodes with anions

MRS Spring Meeting 2010; April 05-09, 2010; San Francisco, Calif., USA

K. Kern, V. Royter, F. I. Corona-Strauss, M. Mariam and D. J. StraussHabituation analysis of chirp vs. tone evoked auditory late responses 32nd International Annual Conference IEEE Engineering in Medicine and Biology Socie-ty: “Merging Medical Humanism and Tech-nology” (EMBC’10); August 31-September 04, 2010; Buenos Aires, Argentina

M. KochEinsatz der Rasterelektronenmikroskopie zur Charakterisierung keramischer Membranen 20. Treffen des AK Keramische Membra-nen, Dechema; May 06, 2010; Frankfurt am Main

A. Kraegeloh, S. Schübbe, S. Kiefer, C. Cavelius, C. Schumann and M. KochNanoparticle cell interactions: insights by microscopical and chemical analyses NanoMed - 7th International Conference on Biomedical Applications of Nanotechnolo-gy; December 02-03, 2010; Berlin

T. KrausRegular particle superstructures: from fun-damental to engineering problems Harvard University; July 16, 2010; Cam-bridge, MA, USA

T. KrausSupraparticles with Lennard-Jones cluster geometries Gordon Research Conference on Nanos-tructure Fabrication, Tilton School; July 18-23, 2010; Tilton, NH, USA

T. KrausMobility of nanoparticles in polymer mat-rices DFG SPP1568 Kick-off Meeting, Friedrich-Schiller-University; October 01, 2010; Jena

T. KrausExchangable nanoparts: building materials and devices from nanoparticles Ringvorlesung Mikrotechnologie und Na-nostrukturen; December 06, 2010; Saar-brücken

E. KronerAdhesion measurements on structured PDMS surfaces using flat probes with con-trolled alignment MRS Fall Meeting 2010; November 29-De-cember 03, 2010; Boston, Mass., USA

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E. Arzt und MitarbeiterInnenNanoBioMaterialien IVorlesung und ÜbungUniversität des Saarlandes, INM, Saarbrücken

E. ArztINM-KolloquiumKolloquiumUniversität des Saarlandes / INM, Saarbrü-cken

R. BennewitzExperimentalphysik IVa (Festkörperphysik I) (EP IV)Vorlesung und ÜbungUniversität des Saarlandes, Saarbrücken

T. MüllerSuperparamagneti sche Nanoparti kel – Syn-these und EinsatzVorlesung für Studierende Maschinenbau im 5.+6. Semester – Fachrichtung Produk-ti onstechnik mit Wahlpfl ichtf ach Nanotech-nologieASW Berufsakademie Saarland, St. IngbertVorlesung am 06.10.2009

T. MüllerSelbstreinigende Oberfl ächen – Immer sau-ber durch PhotokatalyseVorlesung für Studierende Maschinenbau im 5.+6. Semester – Fachrichtung Produkti ons-technik mit Wahlpfl ichtf ach NanotechnologieASW Berufsakademie Saarland, St. IngbertVorlesung am 06.10.2009

D. StraussQuerschnitt sfach 11 – Seminar RadiologieSeminarUniversität des Saarlandes, Saarbrücken

M. Veith u.aAnorganische und Organometallische Che-mieVorlesungUniversité Straßbourg / Ecole Européene de Chimie, Polymères et Matériaux, Stras-bourg, France

M. VeithAllgemeine Chemie (AC00)VorlesungUniversität des Saarlandes, Saarbrücken

M. VeithAnorganisches KolloquiumKolloquiumUniversität des Saarlandes, Saarbrücken

S. Schmitz-StöweKineti c investi gati ons on TiO2 nanoparti cles as photo initi ators for UV-polymerizati on in acrylic matrix SPIE Photonics West - MOEMS-MEMS; Ja-nuary 26, 2010; San Francisco, Calif., USA

A. S. SchneiderCorrelati on between criti cal temperature and strength of small-scale bcc pillars Nanobrücken - Nanomechanical Testi ng Workshop and Hysitron User Meeti ng; Fe-bruary 25-26, 2010; Saarbrücken

A. S. Schneider, B. G. Clark, C. P. Frick, P. A. Gruber and E. ArztEff ect of pre-straining on the size eff ect in molybdenum pillars MRS Fall Meeti ng; November 29-December 03, 2010; Boston, Mass., USA

D. J. StraussVon Stämpfl i, Hodgkin und Huxley zur ska-lenübergreifenden Hirnforschung und Neu-rotechnologie Medizinische Fakultät der UdS; December 03, 2010; Homburg

I. M. WeissNacre inspired control of phase transiti ons in multi -component systems Vorbereitungstreff en zum DFG Schwer-punktprogramm 1569 “Generati on of Mul-ti -functi onal Inorganic Materials by Mole-cular Bionics”; October 25, 2010; Stutt gart

I. M. WeissBiological materials: From enzymes to structural polymers DGM Arbeitskreis “Vom Gen zum Materi-al”; November 04, 2010; Stutt gart

K. A. Yasakau, M. Witt mar, M. L. Zhe-ludkevich and M. G. S. FerreiraEIS study of nanostructured cerium molyb-date doped sol-gel fi lms on 2024 aluminum alloy 217th ECS Meeti ng; April 25-30, 2010; Van-couver, Canada

Lehrveranstaltungen / LecturesWintersemester 2009/10

C. AktasChemische NanotechnologieVorlesungFachhochschule Kaiserslautern / Campus Zweibrücken

J. Lacava and T. KrausEmulsion-based assembly of nanoparti cles PhD Student’s Day; February 18, 2010; Saarbrücken

J.-S. Lee, U. Rauch, K.-H. Schäfer, A. De-mir, O. C. Aktas, C. K. Akkan and M. VeithImproved neuron cell adhesion and prolife-rati on on engineered surfaces 6th Nanoscience & Nanotechnology Confe-rence (NanoTR-VI); June 15-18, 2010; Izmir, Turkey

T. Lehnert, P. Herbeck-Engel, J. Adam and M. VeithFerroelectric characterizati on of low tem-perature sol-gel bonded parti cles PhD Student‘s Day; February 18, 2010; Saarbrücken

T. LehnertFerroelektrische Charakterisierung von Na-noparti keln Skilizium; March 24, 2010; Engelberg, Swit-zerland

T. Lehnert, J. Adam, R. Drumm, J. Dietz and M. VeithFerroelectric characterizati on of isolated BaTiO3 parti cles 19th Internati onal Symposium on the Ap-plicati ons of Ferroelectrics; August 09-12, 2010; Edinburgh, UK

D. ParetkarBioinspired actuated adhesive systems PhD Student’s Day; February 18, 2010; Saarbrücken

M. QuilitzNeue Materialien: Was ist Nanotechnologie Tag der Off enen Tür der Universität des Saarlandes; June 26, 2010; Saarbrücken

B. Reinhard, M. Bukowski, S. Brück, D. Anschütz, S. Gerbes, A. Laurent and M. VeithDevelopment of inorganic nanoparti cles as carriers for intracellular drug delivery 3rd Sino-German Cooperati on on Nanobio-technology Annual Meeti ng/Conference; June 09, 2010; St. Ingbert

E. D. Sam, M. Kamperman, E. Kroner, P. W. Oliveira and E. ArztMethods for replicati on of gecko-inspired adhesives Sabanci University; November 03, 2010; Is-tanbul, Turkey

Lehrveranstaltungen / Lectures

118

M. VeithEinführung zum Praktikum für Studierende der Biologie, der Physik, der Werkstoffwis-senschaften und der MetalltechnikPraktikumUniversität des Saarlandes, Saarbrücken

M. VeithFortgeschrittenenpraktikum für Lehramts-studierende (FGLa2)PraktikumUniversität des Saarlandes, Saarbrücken

M. VeithGrundlagen der Hauptgruppenchemie (AC01)VorlesungUniversität des Saarlandes, Saarbrücken

M. VeithSeminar für eigene MitarbeiterSeminarUniversität des Saarlandes, Saarbrücken

M. VeithSeminar zum fachdidaktischen Schulprakti-kum (FD2)SeminarUniversität des Saarlandes, Saarbrücken

M. VeithÜbungen zu Grundlagen der Hauptgrup-penchemie (AC01Ü)ÜbungUniversität des Saarlandes, Saarbrücken

M. VeithÜbungen zur Allgemeinen Chemie (AC00Ü)ÜbungUniversität des Saarlandes, Saarbrücken

M. VeithChemische NanotechnologieVorlesungFachhochschule Kaiserslautern / Campus Zweibrücken

I. Weiss, M. EderBotanik – Baupläne und Systematik der PflanzenVorlesung für Studierende des Bachelor-Studienganges BiologieUniversität des Saarlandes, Saarbrücken / Lehrstuhl für Botanik (Prof. Mues) und Lehr-stuhl für Pflanzenbiologie (Prof. Bauer)13.10.-22.10.2009 (Weiss) ; 27.10.-29.10.2009 (Eder)

M. Veith Anorganisches Praktikum für Fortgeschrit-tene (ACF)PraktikumUniversität des Saarlandes, Saarbrücken

M. Veith Chemische Fachdidaktik inklusive Seminar zum Schulpraktikum, Kurs B (Fd1+Fd2)SeminarUniversität des Saarlandes, Saarbrücken

M. Veith Chemische Fachdidaktik, Kurs A (FD1)KursUniversität des Saarlandes, Saarbrücken

M. VeithChemische Fachdidaktik, Kurs A (FD1)KursUniversität des Saarlandes, Saarbrücken

M. VeithChemisches Praktikum für Studierende der Physik, Werkstoffwissenschaften, der Biolo-gie und der Metalltechnik (Lehramt an be-ruflichen Schulen)PraktikumUniversität des Saarlandes, Saarbrücken

M. VeithChemisches Praktikum für Studierende der Physik, Werkstoffwissenschaften, der Biolo-gie und der Metalltechnik (Lehramt an be-ruflichen Schulen)PraktikumUniversität des Saarlandes, Saarbrücken

M. VeithChemisches Praktikum für Studierende der Physik, Werkstoffwissenschaften, der Biolo-gie und der Metalltechnik (Lehramt an be-ruflichen Schulen)PraktikumUniversität des Saarlandes, Saarbrücken

M. VeithChemisches Praktikum mit Seminar für Stu-dierende der Biologie, der Physik, der Werk-stoffwissenschaften und der MetalltechnikPraktikumUniversität des Saarlandes, Saarbrücken

M. VeithEinführung in das Fortgeschrittenenprakti-kum für Lehramtsstudierende (FGLa1)PraktikumUniversität des Saarlandes, Saarbrücken

I. WeissBiochemisches Großpraktikum I, Teil D (Pro-tein- und Enzymreinigung)Kurs und SeminarUniversität Regensburg, Regensburg

I. Weiss, E. WeberAP-III: Molekulare PflanzenbiologiePraktikum / SeminarUniversität des Saarlandes, Saarbrücken / Lehrstuhl für Pflanzenbiologie (Prof. Bauer)

Sommersemester 2010

C. AktasMaterialien aus molekularen Vorstufen (AC9)VorlesungUniversität des Saarlandes, Saarbrücken

C. AktasNanomaterialsVorlesungFachhochschule Kaiserslautern / Campus Zweibrücken

E. Arzt und MitarbeiterInnenNanoBioMaterialien IIVorlesung und ÜbungUniversität des Saarlandes, INM, Saarbrücken

E. ArztINM-KolloquiumKolloquiumUniversität des Saarlandes, INM, Saarbrü-cken

A. Schlarb und MitarbeiterInnenKunststoffverarbeitungVorlesungTechnische Universität Kaiserslautern, Kai-serslautern

A. SchlarbKunststoffe in der FahrzeugtechnikVorlesungTechnische Universität Kaiserslautern, Kai-serslautern

A. Schlarb und MitarbeiterInnenTribologie der KunststoffeVorlesungTechnische Universität Kaiserslautern, Kai-serslautern

119

E. Arzt und MitarbeiterInnenNanoBioMaterialien IVorlesung und ÜbungUniversität des Saarlandes, INM, Saarbrücken

E. ArztINM-KolloquiumKolloquiumUniversität des Saarlandes, INM, Saarbrü-cken

R. Bennewitz und MitarbeiterInnenExperimentalphysik IVa (Festkörperphysik)Vorlesung und ÜbungUniversität des Saarlandes, Saarbrücken

R. Bennewitz (und N. Strobach)Sehen, Beobachten, AbbildenSeminarUniversität des Saarlandes, Saarbrücken

A. SchlarbEinführung in die Kunststofft echnikVorlesungTechnische Universität Kaiserslautern, Kai-serslautern

A. Schlarb und MitarbeiterInnenEinführung in die Verbundwerkstoff eVorlesung Technische Universität Kaiserslautern, Kai-serslautern

A. SchlarbPhysik der Kunststoff eVorlesungTechnische Universität Kaiserslautern, Kai-serslautern

A. Schlarb und MitarbeiterInnenPolymere NanocompositesVorlesungTechnische Universität Kaiserslautern, Kai-serslautern

A. Schlarb und MitarbeiterInnenPrüfverfahren in der Kunststofft echnikVorlesungTechnische Universität Kaiserslautern, Kai-serslautern

D. StraussQuerschnitt sfach 11 - Seminar RadiologieSeminarUniversität des Saarlandes, Saarbrücken

M. VeithMolekülchemie der Hauptgruppenelemen-te I (AC7)Vorlesung

D. StraussNeural und Cogniti ve SystemsVorlesungHochschule für Technik und Wirtschaft des Saarlandes, Saarbrücken, und Universität des Saarlandes, Saarbrücken

D. StraussEinführung in die BiosignalverarbeitungVorlesungHochschule für Technik und Wirtschaft des Saarlandes, Saarbrücken

D. StraussBiomedizinische Signal- und Bildverarbei-tungVorlesungHochschule für Technik und Wirtschaft des Saarlandes, Saarbrücken

D. StraussEinführung in das Neural EngineeringVorlesungHochschule für Technik und Wirtschaft des Saarlandes, Saarbrücken

D. StraussQuerschnitt sfach 11 - Seminar RadiologieSeminarUniversität des Saarlandes, Saarbrücken

M. VeithFestkörperchemie (AC5)VorlesungUniversität des Saarlandes, Saarbrücken

M. VeithMolekülchemie der Hauptgruppenelemen-te II (AC12)VorlesungUniversität des Saarlandes, Saarbrücken

M. VeithSymmetry in ChemistryVorlesung ChemieEcole Polytechnique, Paris-Palaiseau

M. VeithAnorganisches Prakti kum für Fortgeschrit-tene“ (ACF)Prakti kumUniversität des Saarlandes, Saarbrücken

Wintersemester 2010 / 2011

C. AktasChemische NanotechnologieVorlesungFachhochschule Kaiserslautern / Campus Zweibrücken

Universität des Saarlandes, Saarbrücken

I. Weiss, M. EderBOT: Modul Botanik für B.Sc. / LA BiologieVorlesungUniversität des Saarlandes, Saarbrücken / Lehrstuhl für Pfl anzenbiologie (Prof. Bauer)

I. Weiss, M. EderBOT: Modul Botanik für B.Sc. BiologiePrakti kumUniversität des Saarlandes, Saarbrücken / Lehrstuhl für Pfl anzenbiologie (Prof. Bauer)

I. WeissBiochemisches Großprakti kum I, Teil D (Pro-tein- und Enzymreinigung) für B.Sc. Bioche-mie (5. Semester)Kurs und SeminarUniversität Regensburg, Regensburg

I. Weiss, E. WeberAP-III: Molekulare Pfl anzenbiologiePrakti kum / SeminarUniversität des Saarlandes, Saarbrücken / Lehrstuhl für Pfl anzenbiologie (Prof. Bauer)

Weitere Lehrveranstaltungen / Other coursesM. Veith, M. Quilitz u.a.GDCh-Kurs “Chemische Nanotechnologie für Anwendungen in Technik und Medizin”16. – 17.09.2010, Saarbrücken

Patents / PatenteIm Jahr 2010 wurden fünf neue Paten-tanmeldungen hinterlegt, die noch nicht off engelegt worden sind. Es wurden 15 Patente erteilt, davon zwei innerhalb von Europa und 13 auf internati onaler Ebene. Das INM – Leibniz-Insti tut für Neue Mate-rialien unterhält somit 101 akti ve Patent-familien. In 2010, INM has fi led fi ve new patent applicati ons which are not yet published. Fift een patents have been granted. Two of these patents are granted in Europe and thirteen in foreign countries. The INM – Leibniz Insti tute for New Materials has 101 acti ve patent families.

Patents / Patente

120

Kooperationen / Cooperations

von Indium-Zinn-Oxid und deren Verwen-dung“Erfinder: Robert Drumm, Christian Göb-bert, Ralph Nonninger, Stefan Sepeur, Hel-mut Schmidt

Japanisches Patent Nr. 4434494Stammanmeldungstitel: „Verfahren zur Herstellung thermisch verformter, mit ei-nem Sol-Gel-Lack beschichteter Substrate“Erfinder: Rainer Kasemann, Nora Laryea (Kunze), Helmut Schmidt, Stefan Sepeur

Japanisches Patent Nr. 4597368Stammanmeldungstitel: „Nanostrukturierte Formkörper und Schichten und deren Herstel-lung über stabile wasserlösliche Vorstufen“Erfinder: Ertugrul Arpac, Gerhard Jonsch-ker, Hermann Schirra, Helmut Schmidt

Ungarisches Patent Nr. 226919 B1Stammanmeldungstitel: „Verfahren zum Versehen einer metallischen Oberfläche mit einer glasartigen Schicht“Erfinder: Gerhard Jonschker, Martin Men-ning, Helmut Schmidt

Japanisches Patent Nr. 4462640Stammanmeldungstitel: „Hydroxylgrup-pen-arme organisch/anorganische Kompo-site, Verfahren zu deren Herstellung und deren Verwendung“Erfinder: Kira Fries, Martin Mennig, Helmut Schmidt, Ulrich Sohling, Qiwu Xing, Micha-el Zahnhausen

Koreanisches Patent Nr. 10-1004558Stammanmeldungstitel: „Substrate mit Bio-film-hemmender Beschichtung“Erfinder: Carsten Becker-Willinger, Helmut Schmidt

Japanisches Patent Nr. 4646906Stammanmeldungstitel: „Antiadhäsive Hochtemperaturschichten“Erfinder: Mesut Aslan, Robert Drumm, Klaus Endres, Hareesh Nair, Bernd Rein-hard, Helmut Schmidt

Kooperationen / Cooperations

Al Azhar University / Gaza, Palestine

Assiut University / Assiut, Egypt

Bogazici Üniversitesi / Istanbul, Turkey

Bundesanstalt für Materialprüfung / Berlin

NanoBioNet e. V. / Saarbrücken

Erteilte europäische Patente

EP 2049949 B1Titel: “Verbundzusammensetzung für mi-krostrukturierte Schichten“Erfinder: Pamela Kalmes, Michael Veith, Carsten Becker-Willinger, Etsuko Hino, No-rio Ohkuma, Mitsutoshi Noguchi, Yoshika-zu Saito

EP 1883534 B1Titel: “Regenerierbare, strukturierte Plat-te mit Oxidationskatalysatoren“Erfinder: Martin Mennig, Peter William de Oliveira, Helmut Schmidt

Erteilte internationale Patente

Chinesisches Patent Nr. ZL200580013173.6Stammanmeldungstitel: „Amphiphile Na-nopartikel“Erfinder: Murat Akarsu, Ertugrul Arpac, Hel-mut Schmidt

Taiwanesisches Patent Nr. I326292Stammanmeldungstitel: „Zusammenset-zung mit Nichtnewtonschem Verhalten“Erfinder: Martin Mennig, Peter William de Oliveira, Helmut Schmidt

US-Patent Nr. 7799432 B2Stammanmeldungstitel: „Substrate mit Bio-film-hemmender Beschichtung“Erfinder: Carsten Becker-Willinger, Helmut Schmidt

Koreanisches Patent Nr. 100942625Stammanmeldungstitel: „Kunststofffolie mit Mehrschicht-Interferenzbeschichtung“Erfinder: Anette Berni, Martin Mennig, Pe-ter William de Oliveira, Helmut Schmidt

Koreanisches Patent Nr. 100965682Stammanmeldungstitel: „Verfahren zur Herstellung optischer Elemente mit Gradi-entenstruktur“Erfinder: Ulrike Dellwo, Martin Mennig, Pe-ter William de Oliveira, Helmut Schmidt, Heike Schneider

Kanadisches Patent Nr. 2399488 CStammanmeldungstitel: „IR-absorbierende Zusammensetzungen“Erfinder: Ralph Nonninger, Martin Schich-tel, Helmut Schmidt, Martin Jost

Japanisches Patent Nr. 4488623Stammanmeldungstitel: „Verfahren zur Herstellung von Suspensionen und Pulvern

Case Western Reserve University / Cle-veland, OH, USA

Centre de Recherche Public Henri Tu-dor (CRP Henri Tudor) / Luxembourg

Christian-Albrechts-Universität / Kiel

CNRS Laboratoire de Chimie de Coordi-nation (LCC) / Toulouse, France

Consejo Superior de Investigaciones Científicas / Madrid, Spain

Cornell University / Ithaca, NY, USA

Defence Metallurgical Research Labo-ratory (DMRL) / Kanchanbagh, Hy-derabad, Indien

Deutsches Zentrum für Luft- und Raum-fahrt / Köln

Ecole Européene d’Ingénieurs en Génie des Matériaux (EEIGM) / Nancy, France

Ecole Polytechnique / Montreal, Canada

Ecole Polytechnique Fédérale de Lau-sanne (EPFL) / Lausanne, Switzerland

Ecole Supérieure de Physique et de Chimie Industrielles (ESPCI) / Paris, France

Eidgenössisch Technische Hochschule (ETH) Zürich / Zurich, Switzerland

European Synchrotron Radiation Facil-ity / Grenoble, France

Fachhochschule Kaiserslautern / Kaisers-lautern

Fachinformationszentrum Karlsruhe (FIZ) / Eggenstein-Leopoldshafen

Felix-Klein-Zentrum für Mathematik / Kaiserlautern

Flinders University of South Australia / Adelaide, Australia

Forschungszentrum Jülich/ Jülich

Fraunhofer Institut für Biomedizinische Technik (IBMT) / St. Ingbert

Fraunhofer Institut für Solare Energie-systeme (ISE) / Freiburg i.Br.

Fraunhofer Institut für Werkstoffme-chanik (IWM) / Freiburg i.Br.

121

Universität Regensburg

Universität des Saarlandes / Saarbrü-cken

Universität Salzburg / Salzburg, Austria

Universität Siegen

Universität Stutt gart

Universität Tübingen

Universität Ulm

Universität Wien / Wien, Austria

Universitätsklinikum des Saarlandes / Homburg

Université catholique de Louvain / Lou-vain, Belgium

Université de Franche-Comté / Besan-çon, France

Université Pierre et Marie Curie (UPMC) / Paris, France

Universiti Teknikal Malaysia Melaka / Melaka, Malaysia

Universiti Teknologi Malaysia / Johor, Malaysia

Université de Toulouse / Toulouse, France

University of Bari / Bari, Italy

University of California / Berkeley, CA, USA

University of California / Santa Barbara, CA, USA

University of Houston / Houston, TX, USA

University of Leoben / Leoben, Austria

University of Madrid / Madrid, Spain

University of Massachusett s / Amherst, MA, USA

University of Nebraska / Lincoln, NE, USA

University of Notre Dam / Indiana, USA

University of Oxford / Oxford, UK

University of Pavia / Pavia, Italy

Fraunhofer Insti tut für Zerstörungsfreie Prüfverfahren (IZFP) / Saarbrücken

Friedrich-Alexander-Universität / Er-langen-Nürnberg

Georg-August-Universität / Götti ngen

Helmholtz-Insti tut für Pharmazeuti -sche Forschung Saarland (HIPS) / Saar-brücken

Herzzentrum Saar / Völklingen

Hochschule für Technik und Wirtschaft des Saarlandes (HTW) / Saarbrücken

Indian Insti tute of Technology / Ma-dras, India

Insti tut Jean-Pierre Bourgin, INRA-AgroParisTech, INRA Centre de Ver-sailles-Grignon / Versailles, France

Insti tuto de Ceramica y Vidrio / Madrid, Spain

Johannes Gutenberg-Universität /Mainz

John Innes Centre / Colney, Norwich, UK

Karlsruhe Insti tute of Technology / Egg-enstein-Leopoldshafen

Kocaeli Üniversitesi / Kocaeli, Turkey

Korea Insti tute of Science and Technol-ogy (KIST) / Seoul, Republic of Korea

Korean University of Technology and Educati on (KUT) / Chanan, Republic Korea

Lawrence Berkeley Nati onal Laboratory /Berkeley, CA, USA

Leopold-Franzens-Universität Innsbruck /Innsbruck, Austria

Ludwig-Maximilians-Universität / Mün-chen

Max-Planck-Insti tut für Metallforschung /Stutt gart

Max-Planck-Insti tut für Polymerfor-schung / Mainz

McGill University / Montreal, Canada

Michigan Technological University / Houghton, MI, USA

Mid Sweden University / Sundswall, Sweden

Nanyang Technological University (NTU) / Singapur, Singapur

Northwestern University / Chicago Il, USA

Paul Scherrer Insti tut (PSI) / Villigen, Switzerland

Rheinische Friedrich-Wilhelms-Universi-tät / Bonn

Ruhr-Universität Bochum / Bochum

Ruprecht-Karls-Universität / Heidel-berg

Saarländische Universitäts- und Lan-desbibliothek / Saarbrücken

Sandia Nati onal Laboratories / Albu-querque, NM, USA

Saxion University of Applied Sciences / Deventer, The Netherlands

Taibah University / Madina, Saudi Arabia

Technical University of Lisbon / Lisbon, Portugal

Technische Universität Darmstadt

Technische Universität Kaiserslautern

TNO – Netherlands Organisati on for Applied Scienti fi c Research / Eindho-ven, Netherlands

Universidad Iberoamericana / Mexico City, Mexico

Universidade de Aveiro / Aveiro, Portugal

Universidade Federal de Minas Gerais (UFMG) / Belo Horizonte, Brasil

Universidade Sao Paulo / Sao Paulo, Brasil

Universitat Autonoma de Barcelona / Bellaterra, Spain

Universität Basel / Basel, Switzerland

Universität Bayreuth

Universität Hamburg-Harburg

Universität Köln

Universität Mannheim

122

Organisation C. Hartmann, S. de Graaf / Universität des SaarlandesApril 23, 2010, Saarbrücken

Tag der Offenen Tür der Universität des SaarlandesBeiträge & OrganisationM. Koch, E. Kroner, M. Quilitz, C. Sauer / Universität des Saarlandes June 26, 2010, Saarbrücken

Nano-Workshop mit der Kocaeli Uni-versityBeiträge & OrganisationM. Veith, J. Flackus, C. Aktas, P. W. de Oli-veira June 29- July 1, 2010, Saarbrücken

Minisaarland 2010Standbetreuung & VersucheE. Bubel, C. Guth, S. Schumacher, S. SiegristJuly 6-24, 2010

Symposium „Bioinspired Adhesion: From Geckos to New Products“Organisation & BeiträgeE. Arzt, M. Kamperman / Volkswagen Stif-tungJuly 7-9, 2010, Saarbrücken

11. Jahrestreffen des Arbeitskreises Bibliotheken und Informationseinrich-tungen der Leibniz-GemeinschaftOrganisationE. Bubel / AK Bibliotheken und Informati-onseinrichtungen der Leibniz-GemeinschaftSeptember 15-17, 2010, Saarbrücken

GDCh-Seminar Chemische Nanotech-nologien und Anwendungen in Technik und MedizinOrganisation & BeiträgeM. Veith, M. Quilitz, S. HeusingSeptember 16-17, 2010, Saarbrücken

Inovatec - 6th Technological Innovation Exhibition Standbetreuung & BeiträgeR. Rolles, P. W. de Oliveira, M. Quilitz / gw-Saar

University of Pennsylvania / Philadel-phia, PA, USA

University of Tel Aviv / Tel Aviv, Israel

University of Wyoming / Laramie, WY, USA

VTT Technical Research Centre of Fin-land / Espoo, Finland

Weizmann Institute of Science / Reho-vot, Israel

Westfälische Wilhelms-Universität / Münster

Xian Jiaotong University / Xian, China

Zentralinstitut für seelische Gesund-heit / Mannheim

Veranstaltungen / Events

Kick-Off-Meeting FundtriboOrganisationA. SchlarbJanuary 12, 2010

Nanobrücken – Nanomechanical Tes-ting Workshop an Hysitron User Mee-tingOrganisation & BeiträgeR. Bennewitz, E. Arzt (Vorträge: G. Guidoni, A. Schneider) / HysitronFebruary 25 – 26, 2010, Saarbrücken

Girls’ Day am INM „Einblicke in den Na-nokosmos“Organisation & BeiträgeE. Bubel, M. Koch, M. Opsölder, S. SiegristApril, 2010

Hannover Messe 2010StandbetreuungJ. Adam, G. Heppe, P. König, M. QuilitzApril 19-23, 2010, Hannover

Wissenschaftliches Kolloquium und Festakt zur Verabschiedung von Prof. Michael Veith

October 7-8, 2010, Belo Horizonte, MG, Brazil

Kick-Off-Meeting TIGeROrganisationR. BennewitzOctober 13, 2010

Korea-EU High level networking Work-shopBeiträgeR. Rolles, M. Quilitz / KIST EuropeOctober 25, 2010, Saarbrücken

FANAS 2010Organisation & BeiträgeR. Bennewitz, E. Arzt (diverse Posterbeiträ-ge) / European Science FoundationOctober 25-28, 2010, Saarbrücken

Kick-Off-Meeting NanoKonOrganisationA. KraegelohOctober 28, 2010

Wissenswerte Bremen 2010Standbetreuung & BeiträgeC. Jung, M. Quilitz, C. Becker-Willinger / Leibniz-GemeinschaftNovember 8-11, 2010, Bremen

INM-Industrietag 2010Organisation & BeiträgeC. Jung, C. Sauer, E. Arzt, P. W. de Oliveira, C. Becker-Willinger, A. KraegelohNovember 23, 2010, Saarbrücken

NanoMed 2010 – 7th International Conference on Biomedical Applications of NanotechnologyOrganisation & BeiträgeK. Moh, C. Hartmann, M. Veith (Vorträge A. Kraegeloh, C. Aktas)December 1-3, 2010, Berlin

Veranstaltungen / Events

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Organigramm/Organigram

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Nanomer ist ein von INM eingetragener Markenname.

Layout/Satz: J. Pütz

Redaktion: Dr. M. Quilitz, Dr. Ch. Sauer

Korrektur: M. Bonnard, P. Egberts, M. Groh, C. Hartmann, Dr. C. Jung, Dr. K. Moh, Dr. Th. Müller, Dr. C. Schumann

Fotos: INM - Uwe Bellhäuser, das Bilderwerk - Jens Steingässer, jens-steingaesser.de

Druck: Digitaldruck Pirrot GmbH, Saarbrücken-Dudweiler

Titelseite: links: Mikrostrukturen im Reinraum (© jens-steingaesser.de) rechts oben: Mikrolinse mit Antireflex-Oberfläche (© INM) rechts unten: Lungenzelle mit Nanopartikeln (© INM)

INM – Leibniz-Insti tut für Neue Materialien gGmbH

Campus D2 266123 Saarbrückenwww.inm-gmbh.de

Telefon: 0681/9300–0Telefax: 0681/9300–223E-mail: contact@inm-gmbh.de

Wissenschaft licher Geschäft sführer:Prof. Dr. Eduard Arzt (Vorsitz)

Kaufmänischer Geschäft sführer: Dr. Roland Rolles

ISSN: 1864-225X