Abstract |
The dissociation of small poly( methacrylic acid) ( PMAA) cations produced by electrospray was characterized by tandem mass spectrometry. Similarly to PMAA ions produced in the negative ion mode, the two electrosprayed cationic forms, namely [PMAA+Na](+) and [ PMAA-H+2Na](+), were shown to fragment via a major pathway consisting of successive dehydration steps. Elimination of a water molecule would occur between two consecutive acid groups in a charged-remote mechanism and was shown to proceed as many times as pairs of acidic pendant groups were available. As a result, comparing the number of dehydration steps observed in the MS/MS spectrum of two consecutive oligomers from the polymeric distribution reveals the degree of polymerization of the molecule. Secondary less informative reactions were shown to consist of losses of CO and/or CO(2), depending on the nature of the precursor ion. These fragmentation rules could be used to characterize PMAA-based copolymers, as successfully demonstrated for a polymeric impurity in the tested PMAA sample.
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Authors | Rémi Giordanengo, Stéphane Viel, Béatrice Allard-Breton, André Thévand, Laurence Charles |
Journal | Rapid communications in mass spectrometry : RCM
(Rapid Commun Mass Spectrom)
Vol. 23
Issue 11
Pg. 1557-62
(Jun 2009)
ISSN: 1097-0231 [Electronic] England |
PMID | 19399764
(Publication Type: Journal Article)
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Copyright | Copyright (c) 2009 John Wiley & Sons, Ltd. |