Positive mode electrospray tandem mass spectrometry of poly(methacrylic acid) oligomers
Article first published online: 27 APR 2009
Copyright © 2009 John Wiley & Sons, Ltd.
Rapid Communications in Mass Spectrometry
Volume 23, Issue 11, pages 1557–1562, 15 June 2009
How to Cite
Giordanengo, R., Viel, S., Allard-Breton, B., Thévand, A. and Charles, L. (2009), Positive mode electrospray tandem mass spectrometry of poly(methacrylic acid) oligomers. Rapid Commun. Mass Spectrom., 23: 1557–1562. doi: 10.1002/rcm.4040
- Issue published online: 27 APR 2009
- Article first published online: 27 APR 2009
- Manuscript Accepted: 20 MAR 2009
- Manuscript Revised: 18 MAR 2009
- Manuscript Received: 12 JAN 2009
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 CO2, 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. Copyright © 2009 John Wiley & Sons, Ltd.