3

APPLICATIONShimadzu News 3/2004APPLICATION Shimadzu News 3/2004

2

IMPRINTShimadzu NEWS, Customer Magazine of Shimadzu Deutschland GmbH, Duisburg

Publisher:Shimadzu Deutschland GmbHAlbert-Hahn-Str. 6 -10 · 47269 DuisburgTelefon: +49 (0) 203 76 87-0Telefax: +49 (0) 203 76 66 25Email: shimadzu@shimadzu.deInternet: www.shimadzu.de

Editorial Team: Uta SteegerTelefon: +49 (0) 203 76 87-410 Ralf Weber

Design and Production:ME Werbeagentur GWA · Düsseldorf

Circulation:18,000 Copies

©Copyright:Shimadzu Deutschland GmbH, Duisburg, September 2004. Reprint, in whole or in part, issubject to the permission of the editorial office.

Windows is a Trademark of Microsoft Corporation.

throughput of Post-source Decay(PSD-MS/MS) applying CurvedField Reflectron (CFR) tech-nology.

In Shimadzu’s DemonstrationLaboratory at the Department ofAnalytical Chemistry, we rou-tinely solve common MALDI-TOF mass spectrometric tasks

Prof. Dr. Josef Havel, D.Sc., Mgr. Ondrej Sedo and Dr. Milan Alberti˘

Figure 1: LDI-TOF mass spectra of negatively charged tellurium clusters.When laser pulses are focussed on a mixture of two elements or a compound, the formation

of several mixed cluster species is achieved. Figure 2 shows the structure of selected precursors. Mass spectra of negatively charged species obtained from tetra

phosphorus trisulphide are shown in Figure 3 (Page 4)

LabSolutions Software –

one “wave lenght“ for

all your cromatography

needs

Laser Ablation Synthesis and

Simultaneous Mass Spectrometric Analysis

of Inorganic Clusters » 2

Well, cheers! – AAS in drinking water analysis »6

Continuous measurement of ultra pure

water – The TOC-VCSH online Option »8

Double stitched provides more strength –

Production control of fibres using FT-NIR »10

Pyrolysis GC for thermal cracking

feedstocks evaluation »12

Far away, but still within reach –

UV-VIS measurements with fibre-optics –

Successful analyses using routine systems »14

An apple per day keeps the doctor away?! –

Mycotoxins are a world-wide problem »16

Automation using Shimadzu’s

LabSolutions software »18

For practitioners by practitioners – Brand new:

Application Book GC/GCMS, Vol.1 »19

Anniversary prices, highly individual –

20 years of FTIR spectrometry »19

Methods in Cleaning Validation »20

New home for second anniversary »20

ynthesis and ass Spectrometric Analysis ters

Laser Ablation SSimultaneous Mof Inorganic Clus

MALDI-TOF-MS(Matrix Assisted LaserDesorption Ionisation -

Time of Flight Mass Spectrome-try) was introduced in 1988 as amethod of transferring large,labile molecules into the gasphase as intact ions [1, 2]. Todayit is the leading-edge analyticaltool in Proteomics and Genomicsfor the study of peptides, pro-teins, biotechnology and pharma-ceutical products, polymers andalmost any kind of moleculeseven with masses of more than 1 million Dalton. For discoveringthe laser desorption process oflarge biomolecules, Koichi Tana-ka from Shimadzu was awardedthe Nobel prize for Chemistry in 2002.

The principle of MALDI is verysimple: the analyte of interest ismixed with high molar excess ofa matrix compound, usually aweak organic acid. The mixture isplaced on a metallic probe andinserted into the Time of Flightmass spectrometer for Laser Desorption-Ionisation analysis.Irradiation with the laser yieldsionisation while molecular frag-mentation is limited. The matrixstrongly absorbs the laser light ata wavelength for which the ana-lyte is only weakly absorbing,acting as a protonating (positiveion detection) or deprotonating(negative ion detection) agent,essential in the analyte ion for-mation process. Finally, highyield of the intact analyte is

Ondrej Sedo1 and Dr. Milan Alberti2By Prof. Dr. Josef Havel, D.Sc.1, Mgr.

APPLICATION

TIPS & TRICKS

TELEGRAM

SEMINAR

INTERNAL

ˆ

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Te cistyData: Te-reflektron0001.D1 7 Jan 2003 14:27 Cal: refneg 14 Mar 2002 10:01 Kratos PC Axima CFR V2.3.4: Mode reflektron_neg, Power: 90, P.Ext.@ 300 (bin 63)1258 mV(sum = 345890 mV) Profiles 365-639 Unsmoothed

Te2-

Model

Experiment

255.8

253.8

259.8

251.8

252.8

249.8

247.8

377.6

511.5

387.6

383.6

371.7

Molecular formula: Te3 Resolution: 5500 at 50 %

Te cistyData: Te-reflektron0001.D1 7 Jan 2003 14:27 Cal: refneg 14 Mar 2002 10:01Kratos PC Axima CFR V2.3.4: Mode reflektron_neg, Power: 90, P.Ext.@ 300 (bin 63)735 mV(sum = 201995 mV) Profiles 365-639 Unsmoothed

375.6

377.6

379.6

380.6

381.6

382.6

383.6

384.6

385.6

387.6

389.6

373.7

375.7

377.7

379.7

380.7

381.7

382.7

383.7

384.7

385.7

387.7

389.7

Te3-

Te4-

Mass/Charge

Mass/Charge

Mass/Charge%

Int.

% Int.

% Int.

such as peptide, protein andpolymer analysis. We have intro-duced the use of osmium tetrox-ide-bipyridine reagent with theaim of improving MALDI-TOFmass spectrometric and PSDproperties of peptides, focussingon novel neuro-protective pep-tide humanin derivatives [3, 4].Apart from these “classical”

applications, our laboratory isoften faced with tougher chal-lenges. In this article, we wouldlike to draw attention to ratherunusual applications of a com-mercial Shimadzu Biotech AXIMA-CFR MALDI-TOFinstrument for inorganic analysisand/or inorganic synthesis. Thiswork belongs to a large �

achieved, giving rise to sub-fem-tomole or attomole sensitivity.

Among other instruments, AXIMA-CFR plus and AXIMA-QIT of ShimadzuBiotech are popular MALDI-TOF mass spectrometers becauseof their relatively low prices,small dimensions and high

3

APPLICATIONShimadzu News 3/2004APPLICATION Shimadzu News 3/2004

2

IMPRINTShimadzu NEWS, Customer Magazine of Shimadzu Deutschland GmbH, Duisburg

Publisher:Shimadzu Deutschland GmbHAlbert-Hahn-Str. 6 -10 · 47269 DuisburgTelefon: +49 (0) 203 76 87-0Telefax: +49 (0) 203 76 66 25Email: shimadzu@shimadzu.deInternet: www.shimadzu.de

Editorial Team: Uta SteegerTelefon: +49 (0) 203 76 87-410 Ralf Weber

Design and Production:ME Werbeagentur GWA · Düsseldorf

Circulation:18,000 Copies

©Copyright:Shimadzu Deutschland GmbH, Duisburg, September 2004. Reprint, in whole or in part, issubject to the permission of the editorial office.

Windows is a Trademark of Microsoft Corporation.

throughput of Post-source Decay(PSD-MS/MS) applying CurvedField Reflectron (CFR) tech-nology.

In Shimadzu’s DemonstrationLaboratory at the Department ofAnalytical Chemistry, we rou-tinely solve common MALDI-TOF mass spectrometric tasks

Prof. Dr. Josef Havel, D.Sc., Mgr. Ondrej Sedo and Dr. Milan Alberti˘

Figure 1: LDI-TOF mass spectra of negatively charged tellurium clusters.When laser pulses are focussed on a mixture of two elements or a compound, the formation

of several mixed cluster species is achieved. Figure 2 shows the structure of selected precursors. Mass spectra of negatively charged species obtained from tetra

phosphorus trisulphide are shown in Figure 3 (Page 4)

LabSolutions Software –

one “wave lenght“ for

all your cromatography

needs

Laser Ablation Synthesis and

Simultaneous Mass Spectrometric Analysis

of Inorganic Clusters » 2

Well, cheers! – AAS in drinking water analysis »6

Continuous measurement of ultra pure

water – The TOC-VCSH online Option »8

Double stitched provides more strength –

Production control of fibres using FT-NIR »10

Pyrolysis GC for thermal cracking

feedstocks evaluation »12

Far away, but still within reach –

UV-VIS measurements with fibre-optics –

Successful analyses using routine systems »14

An apple per day keeps the doctor away?! –

Mycotoxins are a world-wide problem »16

Automation using Shimadzu’s

LabSolutions software »18

For practitioners by practitioners – Brand new:

Application Book GC/GCMS, Vol.1 »19

Anniversary prices, highly individual –

20 years of FTIR spectrometry »19

Methods in Cleaning Validation »20

New home for second anniversary »20

ynthesis and ass Spectrometric Analysis ters

Laser Ablation SSimultaneous Mof Inorganic Clus

MALDI-TOF-MS(Matrix Assisted LaserDesorption Ionisation -

Time of Flight Mass Spectrome-try) was introduced in 1988 as amethod of transferring large,labile molecules into the gasphase as intact ions [1, 2]. Todayit is the leading-edge analyticaltool in Proteomics and Genomicsfor the study of peptides, pro-teins, biotechnology and pharma-ceutical products, polymers andalmost any kind of moleculeseven with masses of more than 1 million Dalton. For discoveringthe laser desorption process oflarge biomolecules, Koichi Tana-ka from Shimadzu was awardedthe Nobel prize for Chemistry in 2002.

The principle of MALDI is verysimple: the analyte of interest ismixed with high molar excess ofa matrix compound, usually aweak organic acid. The mixture isplaced on a metallic probe andinserted into the Time of Flightmass spectrometer for Laser Desorption-Ionisation analysis.Irradiation with the laser yieldsionisation while molecular frag-mentation is limited. The matrixstrongly absorbs the laser light ata wavelength for which the ana-lyte is only weakly absorbing,acting as a protonating (positiveion detection) or deprotonating(negative ion detection) agent,essential in the analyte ion for-mation process. Finally, highyield of the intact analyte is

Ondrej Sedo1 and Dr. Milan Alberti2By Prof. Dr. Josef Havel, D.Sc.1, Mgr.

APPLICATION

TIPS & TRICKS

TELEGRAM

SEMINAR

INTERNAL

ˆ

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90

80

70

60

50

40

30

20

10

0

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370 372 374 376 378 380 382 384 386 388 390 392 394

370 372 374 376 378 380 382 384 386 388 390 392 394

250 300 350 400 450 500 550 600

Te cistyData: Te-reflektron0001.D1 7 Jan 2003 14:27 Cal: refneg 14 Mar 2002 10:01 Kratos PC Axima CFR V2.3.4: Mode reflektron_neg, Power: 90, P.Ext.@ 300 (bin 63)1258 mV(sum = 345890 mV) Profiles 365-639 Unsmoothed

Te2-

Model

Experiment

255.8

253.8

259.8

251.8

252.8

249.8

247.8

377.6

511.5

387.6

383.6

371.7

Molecular formula: Te3 Resolution: 5500 at 50 %

Te cistyData: Te-reflektron0001.D1 7 Jan 2003 14:27 Cal: refneg 14 Mar 2002 10:01Kratos PC Axima CFR V2.3.4: Mode reflektron_neg, Power: 90, P.Ext.@ 300 (bin 63)735 mV(sum = 201995 mV) Profiles 365-639 Unsmoothed

375.6

377.6

379.6

380.6

381.6

382.6

383.6

384.6

385.6

387.6

389.6

373.7

375.7

377.7

379.7

380.7

381.7

382.7

383.7

384.7

385.7

387.7

389.7

Te3-

Te4-

Mass/Charge

Mass/Charge

Mass/Charge

% Int.

% Int.

% Int.

such as peptide, protein andpolymer analysis. We have intro-duced the use of osmium tetrox-ide-bipyridine reagent with theaim of improving MALDI-TOFmass spectrometric and PSDproperties of peptides, focussingon novel neuro-protective pep-tide humanin derivatives [3, 4].Apart from these “classical”

applications, our laboratory isoften faced with tougher chal-lenges. In this article, we wouldlike to draw attention to ratherunusual applications of a com-mercial Shimadzu Biotech AXIMA-CFR MALDI-TOFinstrument for inorganic analysisand/or inorganic synthesis. Thiswork belongs to a large �

achieved, giving rise to sub-fem-tomole or attomole sensitivity.

Among other instruments, AXIMA-CFR plus and AXIMA-QIT of ShimadzuBiotech are popular MALDI-TOF mass spectrometers becauseof their relatively low prices,small dimensions and high

n53 40 1

n4 7

resolved using an AXIMA-CFR mass spectrometer [6].It was also shown that byeliminating the formation ofclusters, uranium could bedetected at levels down to 40 femtomoles [7].

Laser ablationsynthesis

In our recentworks we havesuccessfullydemonstrated theuse of AXIMA-CFR instrumen-tation for laser abla-tion synthesis and direct TOFmass spectrometric identificationof tellurium and phosphorus sul-phides [8 - 11]. To achieve theformation of homopolyatomic orcomposite cluster species, an easysample preparation protocol hasbeen developed. Elements, ele-mental mixtures or compositecompounds were suspended in

3 5

PmSn-

TemSn-

0

2

2

multidisciplinary project called“Synthesis, Analysis and Struc-ture of Natural and SyntheticMolecular Ensembles”.

Under reaction conditions differ-ing from transition metals,chalcogens, nonmetals, theiroxides and other compoundsform heterocyclic compounds,polymers or clusters – precur-sors, which have found extensiveuse in nano materials, compositestructures and other high tech-nology materials. For example,chalcogenide glasses based onsulfides, selenides and telluridesof nonmetals or metals havefound use as optical memories,optical fibers, superionic mate-rials and optical filters amongothers.

The goals of the project are thesyntheses of new compoundsbased on inorganic heteroatomiccompounds, for example cyclicor linear phosphazenes and clus-ters of various sulfides, selenides

and tellurides of the 15th groupof the periodic table, and tounderstand the processes leadingto the formation of either hetero-cycles and clusters or polymers,and phenomena occurring in theplume formed by the laser abla-tion of various materials.

Inorganic compounds

Applications of MALDI-TOF-MS instrumentation in inorganicanalysis are rather scarce. In ourlaboratory we have demonstratedseveral applications, for examplethe speciation of rhodium (III)by capillary electrophoresis wasconfirmed with laser desorptionionisation (LDI) using a Shi-madzu Kompact MALDI III [5],and the structure of uraniumoxide clusters (UO3

+, U2O6+,

U3O9+, U4O12

+, U5O15+,

U6O18+, U7O21

+; U2O5+, U3O8

+,U4O11

+, U5O14+, U6O17

+,U7O20

+, U8O23+; U3O12

+,U4O15

+, U5O18+, U6O21

+,U7O21

+, U8O27+ etc.) has been

APPLICATION Shimadzu News 3/2004

4 5

APPLICATIONShimadzu News 3/2004

benzene (1 mg/mL), 1 µL of thesuspension was applied onto thesample probe and allowed to dryat room temperature.

As an example, mass spectraobtained via laser ablation of ele-mental tellurium in negative ionreflectron mode are shown inFigure 1. As the resolutionreaches a value of 6000, isotopicpatterns of the signals can be dis-tinguished, allowing the confir-mation of all observed species.

Laser ablation synthesis from tellurium-sulphur and phos-phorus-sulphur systems has beenthoroughly described in our pre-vious works. Tables 1 and 2 sum-marise species that have beendetected. It is interesting to notethat most of the observed com-pounds have not previously beencharacterised in the literature,e.g. almost all known phospho-rus sulphides possess even num-bers of phosphorus atoms. Total-ly, 68 new PmSn

- and 32 TemSn-

have been identified [8, 9].

When a thin layer of elementalpowder is applied to the sampleprobe, the formation of adductswith copper originating from themetallic substrate can be seen inthe spectra. The contamination iseliminated using a graphite microcrucible as shown in Figure 4. Inthis way compounds that mightdamage the sample plate, such asaggressive liquids, can also beanalyzed.

Conclusion

In conclusion, it was demonstra-ted that laser ablation synthesisof metal-oxides, chalcogens or

mixed chalcogen clustersand/or heterocycles canbe performed efficientlyusing a commercialMALDI-TOF-MS

instrumentation such as Shi-madzu Biotech’s AXIMA-CFR.The great advantage of thisapproach is that synthesizedproducts can be analysed imme-diately using TOF mass spec-trometry. The methods describedopen new possibilities in study

References[01] Tanaka K., Waki H., Ido Y., Akita S., Yoshida Y.,

Yoshida T., Protein and Polymer Analyses up to

m/z 100,000 by Laser Ionization Time-of-flight

Mass Spectrometry, Rapid Commun. Mass

Spectrom. 1988, 8, 151-53.

[02] Karas M., Hillenkamp F., Laser Desorption Ioni-

zation of Proteins with Molecular Masses

Exceeding 10000 Daltons, Anal. Chem. 1988, 60,

2299 - 2301.

[03] Sedo O., Billová S., Pena-Méndez E.M., Palecek

E., and Havel J., Derivatisation of peptides with

osmium tetroxide, 2,2´-bipyridine: Capillary

electrophoretic and MALDI-TOF mass spectro-

metric study, Anal. Chim. Acta 515, Issue 2,

12 July 2004, Pages 261 - 269, 2004.

[04] Sedo O., Novotná K., and Havel J., Advantages

of osmium tetroxide, 2,2- bipyridine derivatisa-

tion of peptides for their MALDI-TOF MS Post-

Source Decay analysis, Rapid Commun. Mass

Spectrom. 2004, 18, 1 - 6.

[05] Sánchez J. M., Hidalgo M., Havel J., Salvadó V.,

The speciation of rhodium(III) in hydrochloric

acid media by capillary zone electrophoresis,

Talanta 2002, 56, 1061 - 1071.

[06] Soto-Guerrero J., Gajdosová D., Havel J.,

Uranium Oxide Clusters by Laser Desorption

Ionisation During MALDI-TOF MS Analysis of

Uranium(VI), J. Radioanal. Nucl. Chem. 2001,

249, 139 - 143.

[07] Havel J., Soto-Guerrero J., Matrix Assisted

Laser Desorption Ionization (MALDI) and Laser

Desorption Ionization (LDI) Mass Spectrometry

for Trace Uranium Determination. The use of

C60-Fullerene as a Matrix, J. Radioanal. Nucl.

Chem. accepted 2003, in print, 2004.

[08] Alberti M., Sedo O., Havel J., Laser ablation

synthesis and TOF mass spectrometric identi-

fication of tellurium, sulphur and mixed

tellurium-sulphur clusters, Polyhedron 2003, 22,

2601 - 2605.

[09] Sedo O., Vorác Z., Alberti M., Havel J.,

New Phosphorus-Sulphur heterocycles and/or

clusters, Polyhedron 2004, 23, 1199 - 1206.

[10] Sedo O., Havel J., PSD in MALDI/LDI TOF MS:

Efficient Tool for Structure Analysis of Inorga-

nic, Organic and Biomolecules, ASMS 2004

(Nashville, Tennessee), Poster MPM 195.

[11] Havel J., Sedo O., Alberti M., TOF MS Instru-

mentation – Effective Tool for Laser Ablation

Micro Synthesis and Simultaneous Analysis

of Inorganic Clusters, ASMS 2004 (Nashville,

Tennessee), Poster ThPG 110.

1 Department of Analytical Chemistry, Faculty of

Science, Masaryk University, Kotlárská 2, 611 37

Brno, Czech Republic2 Research Department for the Structural Study of

Molecular Ensembles, Faculty of Science, Masa-

ryk University, Kotlárská 2, 611 37 Brno,

Czech Republic

*Corresponding autor: e-mail:

havel@chemi.muni.cz

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526 528 530 532 534 536 538 540 542

100 150 200 250 300 350 400 450 500 550 600 650 700 750

P4S3Data: lin-nizka0001.B3 18 Dec 2002 16:58 Cal: sona2 9 Feb 2004 16:47 Kratos PC Axima CFR V2.3.4: Mode linear_neg. Power: 80, P.Ext.@500 (bin 63)389 mV(sum = 94624 mV) Profiles 1-243 Unsmoothed

78.9

95.4

94.9

111.4

127.9192.9

174.9

176.9

220.9

250.8

282.8

314.8

254.9316.8

270.9

332.9 380.8

374.8

378.8

376.8

438.8

440.8502.7

532.6

566.6628.6

218.8

127.4

128.9

126.9

528.7

530.7

532.6

533.7

534.7

535.7

536.7

538.8

P4S3Data: lin-nizka0001.B3 18 Dec 2002 19:58 Cal: sona2 9 Feb 2004 16:47 Kratos PC Axima CFR V2.3.4: Mode linear_neg. Power: 80. P.Ext.@500 (bin 63)56 mV(sum = 13490 mV) Profiles 1-243 Unsmoothed

P15S2-

P13S4-

P11S6-

P9S8-

P932S734S-

Mass/Charge

Mass/Charge

% Int.

% Int.

Figure 3: The formation of dozens of mixed clusters can be seen. In a detailed view, an example of spectra interpretation is shown, confirming the necessity of

isotopic pattern modelling

10123456

m

6 8 9 10 11 12 13 14 15

11

m

0123456789101112131415161718192021

6 7 8 9 10

processes leading to the forma-tion of new compounds andmaterials.

Figure 2: Structure of P4, S8

and P4S10, used as synthetic

precursors

Table 1: Review of all TemSn- species synthesised from a

tellurium-sulphur system

Table 2: Review of all PmSn- species synthesised from a phosphorus-sulphur

system, including phosphorus sulphides P4S3 and P4S10

Figure 4: Samples prepared for LDI-TOF mass spectrometric analysis

Acknowledgement

This work was supported by theMinistry of Education, Youthand Sport of the Czech Republic,project No. MS 143 100011.

ˆ ˆˆ

ˆ

ˆ

ˆ ˆ

ˆ

ˆ

ˆ

ˆ

ˆ

n53 40 1

n4 7

resolved using an AXIMA-CFR mass spectrometer [6].It was also shown that byeliminating the formation ofclusters, uranium could bedetected at levels down to 40 femtomoles [7].

Laser ablationsynthesis

In our recentworks we havesuccessfullydemonstrated theuse of AXIMA-CFR instrumen-tation for laser abla-tion synthesis and direct TOFmass spectrometric identificationof tellurium and phosphorus sul-phides [8 - 11]. To achieve theformation of homopolyatomic orcomposite cluster species, an easysample preparation protocol hasbeen developed. Elements, ele-mental mixtures or compositecompounds were suspended in

3 5

PmSn-

TemSn-

0

2

2

multidisciplinary project called“Synthesis, Analysis and Struc-ture of Natural and SyntheticMolecular Ensembles”.

Under reaction conditions differ-ing from transition metals,chalcogens, nonmetals, theiroxides and other compoundsform heterocyclic compounds,polymers or clusters – precur-sors, which have found extensiveuse in nano materials, compositestructures and other high tech-nology materials. For example,chalcogenide glasses based onsulfides, selenides and telluridesof nonmetals or metals havefound use as optical memories,optical fibers, superionic mate-rials and optical filters amongothers.

The goals of the project are thesyntheses of new compoundsbased on inorganic heteroatomiccompounds, for example cyclicor linear phosphazenes and clus-ters of various sulfides, selenides

and tellurides of the 15th groupof the periodic table, and tounderstand the processes leadingto the formation of either hetero-cycles and clusters or polymers,and phenomena occurring in theplume formed by the laser abla-tion of various materials.

Inorganic compounds

Applications of MALDI-TOF-MS instrumentation in inorganicanalysis are rather scarce. In ourlaboratory we have demonstratedseveral applications, for examplethe speciation of rhodium (III)by capillary electrophoresis wasconfirmed with laser desorptionionisation (LDI) using a Shi-madzu Kompact MALDI III [5],and the structure of uraniumoxide clusters (UO3

+, U2O6+,

U3O9+, U4O12

+, U5O15+,

U6O18+, U7O21

+; U2O5+, U3O8

+,U4O11

+, U5O14+, U6O17

+,U7O20

+, U8O23+; U3O12

+,U4O15

+, U5O18+, U6O21

+,U7O21

+, U8O27+ etc.) has been

APPLICATION Shimadzu News 3/2004

4 5

APPLICATIONShimadzu News 3/2004

benzene (1 mg/mL), 1 µL of thesuspension was applied onto thesample probe and allowed to dryat room temperature.

As an example, mass spectraobtained via laser ablation of ele-mental tellurium in negative ionreflectron mode are shown inFigure 1. As the resolutionreaches a value of 6000, isotopicpatterns of the signals can be dis-tinguished, allowing the confir-mation of all observed species.

Laser ablation synthesis from tellurium-sulphur and phos-phorus-sulphur systems has beenthoroughly described in our pre-vious works. Tables 1 and 2 sum-marise species that have beendetected. It is interesting to notethat most of the observed com-pounds have not previously beencharacterised in the literature,e.g. almost all known phospho-rus sulphides possess even num-bers of phosphorus atoms. Total-ly, 68 new PmSn

- and 32 TemSn-

have been identified [8, 9].

When a thin layer of elementalpowder is applied to the sampleprobe, the formation of adductswith copper originating from themetallic substrate can be seen inthe spectra. The contamination iseliminated using a graphite microcrucible as shown in Figure 4. Inthis way compounds that mightdamage the sample plate, such asaggressive liquids, can also beanalyzed.

Conclusion

In conclusion, it was demonstra-ted that laser ablation synthesisof metal-oxides, chalcogens or

mixed chalcogen clustersand/or heterocycles canbe performed efficientlyusing a commercialMALDI-TOF-MS

instrumentation such as Shi-madzu Biotech’s AXIMA-CFR.The great advantage of thisapproach is that synthesizedproducts can be analysed imme-diately using TOF mass spec-trometry. The methods describedopen new possibilities in study

References[01] Tanaka K., Waki H., Ido Y., Akita S., Yoshida Y.,

Yoshida T., Protein and Polymer Analyses up to

m/z 100,000 by Laser Ionization Time-of-flight

Mass Spectrometry, Rapid Commun. Mass

Spectrom. 1988, 8, 151-53.

[02] Karas M., Hillenkamp F., Laser Desorption Ioni-

zation of Proteins with Molecular Masses

Exceeding 10000 Daltons, Anal. Chem. 1988, 60,

2299 - 2301.

[03] Sedo O., Billová S., Pena-Méndez E.M., Palecek

E., and Havel J., Derivatisation of peptides with

osmium tetroxide, 2,2´-bipyridine: Capillary

electrophoretic and MALDI-TOF mass spectro-

metric study, Anal. Chim. Acta 515, Issue 2,

12 July 2004, Pages 261 - 269, 2004.

[04] Sedo O., Novotná K., and Havel J., Advantages

of osmium tetroxide, 2,2- bipyridine derivatisa-

tion of peptides for their MALDI-TOF MS Post-

Source Decay analysis, Rapid Commun. Mass

Spectrom. 2004, 18, 1 - 6.

[05] Sánchez J. M., Hidalgo M., Havel J., Salvadó V.,

The speciation of rhodium(III) in hydrochloric

acid media by capillary zone electrophoresis,

Talanta 2002, 56, 1061 - 1071.

[06] Soto-Guerrero J., Gajdosová D., Havel J.,

Uranium Oxide Clusters by Laser Desorption

Ionisation During MALDI-TOF MS Analysis of

Uranium(VI), J. Radioanal. Nucl. Chem. 2001,

249, 139 - 143.

[07] Havel J., Soto-Guerrero J., Matrix Assisted

Laser Desorption Ionization (MALDI) and Laser

Desorption Ionization (LDI) Mass Spectrometry

for Trace Uranium Determination. The use of

C60-Fullerene as a Matrix, J. Radioanal. Nucl.

Chem. accepted 2003, in print, 2004.

[08] Alberti M., Sedo O., Havel J., Laser ablation

synthesis and TOF mass spectrometric identi-

fication of tellurium, sulphur and mixed

tellurium-sulphur clusters, Polyhedron 2003, 22,

2601 - 2605.

[09] Sedo O., Vorác Z., Alberti M., Havel J.,

New Phosphorus-Sulphur heterocycles and/or

clusters, Polyhedron 2004, 23, 1199 - 1206.

[10] Sedo O., Havel J., PSD in MALDI/LDI TOF MS:

Efficient Tool for Structure Analysis of Inorga-

nic, Organic and Biomolecules, ASMS 2004

(Nashville, Tennessee), Poster MPM 195.

[11] Havel J., Sedo O., Alberti M., TOF MS Instru-

mentation – Effective Tool for Laser Ablation

Micro Synthesis and Simultaneous Analysis

of Inorganic Clusters, ASMS 2004 (Nashville,

Tennessee), Poster ThPG 110.

1 Department of Analytical Chemistry, Faculty of

Science, Masaryk University, Kotlárská 2, 611 37

Brno, Czech Republic2 Research Department for the Structural Study of

Molecular Ensembles, Faculty of Science, Masa-

ryk University, Kotlárská 2, 611 37 Brno,

Czech Republic

*Corresponding autor: e-mail:

havel@chemi.muni.cz

100

90

80

70

60

50

40

30

20

10

0

0

100

80

90

60

70

30

50

20

40

10

50

526 528 530 532 534 536 538 540 542

100 150 200 250 300 350 400 450 500 550 600 650 700 750

P4S3Data: lin-nizka0001.B3 18 Dec 2002 16:58 Cal: sona2 9 Feb 2004 16:47 Kratos PC Axima CFR V2.3.4: Mode linear_neg. Power: 80, P.Ext.@500 (bin 63)389 mV(sum = 94624 mV) Profiles 1-243 Unsmoothed

78.9

95.4

94.9

111.4

127.9192.9

174.9

176.9

220.9

250.8

282.8

314.8

254.9316.8

270.9

332.9 380.8

374.8

378.8

376.8

438.8

440.8502.7

532.6

566.6628.6

218.8

127.4

128.9

126.9

528.7

530.7

532.6

533.7

534.7

535.7

536.7

538.8

P4S3Data: lin-nizka0001.B3 18 Dec 2002 19:58 Cal: sona2 9 Feb 2004 16:47 Kratos PC Axima CFR V2.3.4: Mode linear_neg. Power: 80. P.Ext.@500 (bin 63)56 mV(sum = 13490 mV) Profiles 1-243 Unsmoothed

P15S2-

P13S4-

P11S6-

P9S8-

P932S734S-

Mass/Charge

Mass/Charge

% Int.

% Int.

Figure 3: The formation of dozens of mixed clusters can be seen. In a detailed view, an example of spectra interpretation is shown, confirming the necessity of

isotopic pattern modelling

10123456

m

6 8 9 10 11 12 13 14 15

11

m

0123456789101112131415161718192021

6 7 8 9 10

processes leading to the forma-tion of new compounds andmaterials.

Figure 2: Structure of P4, S8

and P4S10, used as synthetic

precursors

Table 1: Review of all TemSn- species synthesised from a

tellurium-sulphur system

Table 2: Review of all PmSn- species synthesised from a phosphorus-sulphur

system, including phosphorus sulphides P4S3 and P4S10

Figure 4: Samples prepared for LDI-TOF mass spectrometric analysis

Acknowledgement

This work was supported by theMinistry of Education, Youthand Sport of the Czech Republic,project No. MS 143 100011.

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