NEW MATRICES AND ACCELERATING VOLTAGE EFFECTS IN MATRIX-ASSISTED LASER-DESORPTION IONIZATION OF SYNTHETIC-POLYMERS

被引:47
作者
TANG, XD
DREIFUSS, PA
VERTES, A
机构
[1] GEORGE WASHINGTON UNIV,DEPT CHEM,WASHINGTON,DC 20052
[2] WR GRACE & CO CONN,WASHINGTON RES CTR,COLUMBIA,MD 21044
关键词
D O I
10.1002/rcm.1290091212
中图分类号
Q5 [生物化学];
学科分类号
071010 ; 081704 ;
摘要
Most matrices used in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) have been selected for their sound performance in the detection of proteins. We evaluated a series of new matrices for the analysis of synthetic polymers and compared their performance to that of conventional ones. Among substituted polycyclic aromatic hydrocarbons 1,4-dihydroxy-2-naphthoic acid, 9-anthracenecarboxylic acid (9-ACA), and its mixtures with 5-methoxysalicylic acid ('super' 9-ACA) offered better signal quality for analysis of synthetic polymers. To test the performance of these new matrices, authentic standards of poly(ethylene glycol), poly(propylene glycol), Jeffamine, polybutadiene, poly(methyl methacrylate), poly(dimethyl siloxane), and some of their mixtures were analyzed. By generating mainly [M + Na](+) ions, 9-ACA showed superior performance to most conventional matrices and provided higher effective mass resolution. The 'super' 9-ACA composite matrix was found to be more suitable for larger polymer molecules (>8000 Da). Broader acceptance of MALDI-MS for synthetic polymer analysis has been delayed by systematic differences observed between MALDI-MS and gel permeation chromatography (GPC) in terms of oligomer size distributions (R. S. Lehrle and D. S. Sarson, Rapid Commun. Mass Spectrom., Vol. 9, p. 91 (1995). We found that part of the discrepancy can be explained by the profound dependence of mass distributions on the accelerating voltage of the Lime-of-flight mass spectrometer. With decreasing accelerating voltage both the ion intensity and the mass resolution decreased, and the high-mass end of the mass spectrum became truncated. For example, when the accelerating voltage was changed from 30 kV to 18 kV the center of the peak area distribution for poly(methylmethacrylate) (PMMA) 6000 shifted to lower values by about 210 Da. At the same time, the skewness of the distribution increased tenfold indicating serious discrimination phenomena. These detrimental effects of lower accelerating voltage were particularly strong for relatively large synthetic polymer molecules.
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页码:1141 / 1147
页数:7
相关论文
共 21 条
  • [1] MASS-SPECTROMETRY OF SYNTHETIC-POLYMERS BY UV MATRIX-ASSISTED LASER DESORPTION IONIZATION
    BAHR, U
    DEPPE, A
    KARAS, M
    HILLENKAMP, F
    GIESSMANN, U
    [J]. ANALYTICAL CHEMISTRY, 1992, 64 (22) : 2866 - 2869
  • [2] CALLAHAN JH, UNPUB
  • [3] MEASUREMENT OF PROPAGATION RATE COEFFICIENTS USING PULSED-LASER POLYMERIZATION AND MATRIX-ASSISTED LASER-DESORPTION IONIZATION MASS-SPECTROMETRY
    DANIS, PO
    KARR, DE
    WESTMORELAND, DG
    PITON, MC
    CHRISTIE, DI
    CLAY, PA
    KABLE, SH
    GILBERT, RG
    [J]. MACROMOLECULES, 1993, 26 (24) : 6684 - 6685
  • [4] A FACILE SAMPLE PREPARATION FOR THE ANALYSIS OF SYNTHETIC ORGANIC POLYMERS BY MATRIX-ASSISTED LASER-DESORPTION IONIZATION
    DANIS, PO
    KARR, DE
    [J]. ORGANIC MASS SPECTROMETRY, 1993, 28 (08): : 923 - 925
  • [5] DANIS PO, 1992, ORG MASS SPECTROM, V27, P283
  • [6] DETERMINATION OF MOLECULAR-WEIGHT DISTRIBUTIONS OF POLYMERS BY MALDI-FTMS
    DEY, M
    CASTORO, JA
    WILKINS, CL
    [J]. ANALYTICAL CHEMISTRY, 1995, 67 (09) : 1575 - 1579
  • [7] SECONDARY-ELECTRON EMISSION INDUCED BY IMPACT OF LOW-VELOCITY MOLECULAR-IONS ON A MICROCHANNEL PLATE
    GENO, PW
    MACFARLANE, RD
    [J]. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY AND ION PROCESSES, 1989, 92 : 195 - 210
  • [8] HURST GB, 1995, 42ND P C MASS SPECTR, P975
  • [9] SILVER-NITRATE CHEMICAL IONIZATION FOR ANALYSIS OF HYDROCARBON POLYMERS BY LASER-DESORPTION FOURIER-TRANSFORM MASS-SPECTROMETRY
    KAHR, MS
    WILKINS, CL
    [J]. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY, 1993, 4 (06) : 453 - 460
  • [10] KING RC, 1994, 42ND P C MASS SPECTR, P955