TU Darmstadt HPLC-MALDI-TOF Mass Spectrometry for the Analysis of Complex Polymers H. Pasch German Institute for Polymers (Deutsches Kunststoff-Institut) Darmstadt, Germany hpasch@dki.tu-darmstadt.de 2004 Fall Workshop of the American Society for Mass Spectrometry Baltimore, December 9-10, 2004 Das DKI ist eine Einrichtung der Forschungsgesellschaft Kunststoffe e.v., Mitglied der 1 Shimadzu's Scientist Koichi Tanaka Received obel Prize in Chemistry 2002 On December 10 th, 2002, obel Prize Award Ceremony took place in Stockholm, Sweden. Koichi Tanaka, fellow of Shimadzu Corporation, received his obel medal and diploma in Chemistry from his Majesty the King of Sweden, King Carl XVI Gustaf. Tanaka received the prize for the development of soft desorption ionization methods for mass spectrometric analyses of biological macromolecules to identify and reveal the structures of such molecules. Tanaka is the 12th Japanese citizen who has received a obel Prize. 2 1
Why Coupling of LC and MALDI-TOF MS? Samples with high polydispersity (M w /M n >1,2) GPC calibration without calibration standards Analysis of complex polymers multiple distributions: FTD-MMD, CCD-MMD Determination of small amounts of by-products High-throughput analysis for combinatorial materials research 3 Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry 4 2
Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry 5 Principle Ideas of MALDI-TOF MS upon laser irradiation all molecules obtain similar energies E kin = 0.5 m v 2 at similar kinetic energies: molecules of different masses have different flight velocities (higher m means lower v) flight time in the TOF mass analyzer T ~ L (m/z U) 0.5 T - ion flight time, L - length of drift tube, m - ion mass, z - ion charge, U - acceleration voltage 6 3
Sample Preparation for MALDI-TOF MS Salt Matrix Solution Polymer Solution OH OH OH Deposition HO COOH OH Drying 7 Interpretation of a MALDI-TOF Spectrum -Anionically polymerized polystyrene- 8706 = 82 (n) x 104.15 (Styrene) + 57 (Butyl) + 1 (Hydrogen) + 108 (Ag + ) 8 4
Off-line Coupling of GPC and MALDI-TOF - GPC Separation of Polycaprolactone - Calibration???? 9 10000 2,000 g/mol 900 g/mol Off-line Coupling of GPC and MALDI-TOF - GPC Separation of Polycaprolactone - Internal calibration for more accurate molar masses 10 5
Off-line Coupling of LC and MALDI-TOF - Analysis of Polyethylene Oxides - Alk(Ar)-OH + CH 2 -CH 2 Alk(Ar)-(OCH 2 CH 2 ) n -OH O secondary reactions additional functionality fractions H-(OCH 2 CH 2 ) n -OH -(OCH 2 CH 2 ) n - Alk(Ar)-(OCH 2 CH 2 ) n -OAlk(Ar) 11 Off-line Coupling of LC and MALDI-TOF - Analysis of Polyethylene Oxides - Functionality type and oligomer separation 12 6
Off-line Coupling of LC and MALDI-TOF - Analysis of Polyethylene Oxides - Spectrum of fraction 1 GPC calibration of 13 functionality fractions Analysis of Methoxylated Melamine-Formaldehyde Resins H 2 H 2 + CH2O + CH3OH CH 3 OCH 2 CH 3 OCH 2 CH 2 OCH 3 CH 2 OCH 3 H 2 CH 3 OCH 2 CH 2 OCH 3 CH 3 OCH 2 CH 3 OCH 2 CH 2 OCH 3 CH 2 CH 3 OCH 2 OCH 2 CH 2 OCH 3 CH 2 OCH 3 CH 3 OCH 2 CH 2 OCH 3 CH 3 OCH 2 CH 2 OCH 3 14n 7
GPC of a Methoxylated Melamine-Formaldehyde Resin 15 MALDI-TOF Spectra of GPC Fractions of a Methoxylated Melamine-Formaldehyde Resin 16 8
Enlarged Tetramer Region of the MALDI-TOF Spectrum 17 Chemical Structures of the Tetramers M+a + = 1313 Da M+a + = 1343 Da M+a + = 1387 Da 18 9
On-line Coupled GPC/MALDI-TOF MS Injector UV- / RI-Detector Pump Sample Eluent SEC Columns 10 10:1 1 Interface 19 Schematic Presentation of a LC/MALDI-TOF Interface (Lab Connections) Eluate itrogen Heating MALDI Target X,Y-Movable Table 20 10
Lab Connections LC/MALDI-TOF Interface Model 600 and Pre-coated MALDI Targets 21 Analysis of PnBMA-b-PMMA by GPC/MALDI-TOF 0.018 0.016 0.014 0.012 0.010 Spannung [V] 0.008 0.006 0.004 0.002 0.000 PSS WinGPC scientific V 4.0 beta-12 23 24 25 26 27 28 29 30 Elutionsvolumen [ml] 22 11
Analysis of PnBMA-b-PMMA by GPC/MALDI-TOF X (MMA) Y (nbma) Calc. Exp. 18 14 3818 Da 3818 Da 21 12 3834 Da 3835 Da 24 10 3850 Da 3850 Da 17 15 3860 Da 3860 Da 20 13 3876 Da 3877 Da 23 11 3892 Da 3893 Da 23 LC/MALDI-TOF Interface (BAI) Liquid Chromatography SEC / CC Interface BAI Probot MALDI-TOF-MS Kratos Compact IV SEC / CC Waste 0,5 ml/min 1 40 RI- Detector Matrix 1 Waste 5 Probot MALDI- TOF-MS Data Processing Operation Data Processing 24 12
LC/MALDI-TOF Interface PROBOT (BAI) 25 LC-CC/MALDI-TOF Analysis of Polypropylene Oxide Triols 0.12 Spannung [V] 0.10 0.08 0.06 0.04 0.02 0.00 PPG with Allylic Endgroup or Cyclic Fraction PPG Glycerol Started PPO H 2 C HC H 2 C O O O CH CH2 O CH 3 CH CH 2 O CH 3 CH CH2 O CH 3 PSS WinGPC scientific V 4.02 x y z H H H 2 4 6 8 10 12 Elutionsvolumen [ml] 26 13
LC-CC/MALDI-TOF Analysis of Polypropylene Oxide Triols PPO Monool with Allylic Endgroup or Cyclic PPO Spannung [V] 0.12 0.10 0.08 0.06 0.04 0.02 0.00 PSS WinGPC scientific V 4.02 2 4 6 8 10 12 Elutionsvolumen [ml] PPG 0.12 0.10 0.08 Spannung [V] 0.06 0.04 0.02 0.00 PSS WinGPC scientific V 4.02 2 4 6 8 10 12 Elutionsvolumen [ml] 27 LC-CC/MALDI-TOF Analysis of Polypropylene Oxide Triols Glycerol Started PPO Spannung [V] 0.12 0.10 0.08 0.06 0.04 0.02 0.00 PSS WinGPC scientific V 4.02 2 4 6 8 10 12 Elutionsvolumen [ml] Glycerol Started PPO Spannung [V] 0.12 0.10 0.08 0.06 0.04 0.02 0.00 PSS WinGPC scientific V 4.02 2 4 6 8 10 12 Elutionsvolumen [ml] 28 14
Direct Coupling of LC and MALDI-TOF MS Aerosol MALDI-TOF instrument coupled to GPC X. Fei, K.K. Murray, Anal. Chem. 68 (1996) 3555 29 Direct Coupling of LC and MALDI-TOF MS Spectra of fractions Single ion chromatograms 30 15
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