TY - JOUR
T1 - Influence of Charge State and Sodium Cationization on the Electron Detachment Dissociation and Infrared Multiphoton Dissociation of Glycosaminoglycan Oligosaccharides
AU - Wolff, Jeremy J.
AU - Laremore, Tatiana N.
AU - Busch, Alexander M.
AU - Linhardt, Robert J.
AU - Amster, I. Jonathan
N1 - Funding Information:
The authors acknowledge the seminal contributions of Roman Zubarev to the field of electron–ion interactions, and offer congratulations on his selection as a Biemann awardee, and gratefully acknowledge financial support from the National Institutes of Health Grant 2R01-GM038060-16.
PY - 2008/6
Y1 - 2008/6
N2 - Electron detachment dissociation (EDD) Fourier transform mass spectrometry has recently been shown to be a useful method for tandem mass spectrometry analysis of sulfated glycosaminoglycans (GAGs). EDD produces abundant glycosidic and cross-ring fragmentations that are useful for localizing sites of sulfation in GAG oligosaccharides. Although EDD fragmentation can be used to characterize GAGs in a single tandem mass spectrometry experiment, SO3 loss accompanies many peaks and complicates the resulting mass spectra. In this work we demonstrate the ability to significantly decrease SO3 loss by selection of the proper ionized state of GAG precursor ions. When the degree of ionization is greater than the number of sulfate groups in an oligosaccharide, a significant reduction in SO3 loss is observed in the EDD mass spectra. These data suggested that SO3 loss is reduced when an electron is detached from carboxylate groups instead of sulfate. Electron detachment occurs preferentially from carboxylate versus sulfate for thermodynamic reasons, provided that carboxylate is in its ionized state. Ionization of the carboxylate group is achieved by selecting the appropriate precursor ion charge state, or by the replacement of protons with sodium cations. Increasing the ionization state by sodium cation addition decreases, but does not eliminate, SO3 loss from infrared multiphoton dissociation of the same GAG precursor ions.
AB - Electron detachment dissociation (EDD) Fourier transform mass spectrometry has recently been shown to be a useful method for tandem mass spectrometry analysis of sulfated glycosaminoglycans (GAGs). EDD produces abundant glycosidic and cross-ring fragmentations that are useful for localizing sites of sulfation in GAG oligosaccharides. Although EDD fragmentation can be used to characterize GAGs in a single tandem mass spectrometry experiment, SO3 loss accompanies many peaks and complicates the resulting mass spectra. In this work we demonstrate the ability to significantly decrease SO3 loss by selection of the proper ionized state of GAG precursor ions. When the degree of ionization is greater than the number of sulfate groups in an oligosaccharide, a significant reduction in SO3 loss is observed in the EDD mass spectra. These data suggested that SO3 loss is reduced when an electron is detached from carboxylate groups instead of sulfate. Electron detachment occurs preferentially from carboxylate versus sulfate for thermodynamic reasons, provided that carboxylate is in its ionized state. Ionization of the carboxylate group is achieved by selecting the appropriate precursor ion charge state, or by the replacement of protons with sodium cations. Increasing the ionization state by sodium cation addition decreases, but does not eliminate, SO3 loss from infrared multiphoton dissociation of the same GAG precursor ions.
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U2 - 10.1016/j.jasms.2008.03.010
DO - 10.1016/j.jasms.2008.03.010
M3 - Article
C2 - 18499037
AN - SCOPUS:43549114332
SN - 1044-0305
VL - 19
SP - 790
EP - 798
JO - Journal of the American Society for Mass Spectrometry
JF - Journal of the American Society for Mass Spectrometry
IS - 6
ER -