Abstract
Fast atom bombardment mass spectrometry of choline phospholipids produces negative ions characteristic of the intact molecule and tandem mass spectrometry of collision-induced decomposition of M-15 anions characterizes both the identity and substituent position of radyl groups. Certain choline phospholipid molecular species which may be of special interest in the generation of platelet activating factor contain a highly unsaturated fatty acyl substituent atsn-2 and an ether radyl group atsn-1; other choline phospholipid molecular species which contain esterified arachidonic acid are of interest as potential sources of arachidonate for eicosanoid biosynthesis. Collisional activated decomposition of 1-hexadecanoyl-2-arachidonoyl-sn-glycerophosphocholine produce abundant carboxylate anions atm/z 303 (arachidonate) andm/z 255 (hexadecanoate) in a ratio of 3∶1, diagnostic for thesn-2 arachidonoyl position. The ether analog, 1-O-hexadecyl-2-arachidonoyl glycerophosphocholine, produces only one collision-induced dissociation ion atm/z 303 and no product ions corresponding to the ether substituent atsn-1. Molecular weight information from the M-15 ion combined with the CID generated carboxylate anions completely characterize these important phospholipids.
Precursor ion studies of M-15 anions from glycerophosphocholine lipids indicate that this ion is derived directly from a unique adduct ion formed by attachment of the molecular species to a matrix alkoxide ion, neutralizing the positive charge of the quaternary choline nitrogen. Decomposition of this adduct ion yields a methylated matrix molecule and the nominal M-15 ion.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Abbreviations
- B/E:
-
product ion linked scans where the mass spectrometer magnet is scanned while holding the ratio of the magnet field (B) to electric sector voltage (E) constant
- B2/E:
-
precusor ion linked scans where the mass spectrometer magnet is scanned while holding the ratio of the square of the magnetic field (B) to electric sector voltage (E) constant
- CID:
-
collision-induced decomposition
- FAB:
-
fast atom bombardment
- GPCho:
-
glycerophosphocholine
References
Christie, W.W. (1982)Lipid Analysis, 2nd edn., Chapter 8, Pergamon Press, Oxford, U.K.
van den Bosch, H. (1980)Biochim. Biophys. Acta 250, 191–246.
Myher, J.J., Kuksis, A., Marai, L., and Yeang, S.K.F. (1978)Anal. Chem. 50, 557–561.
Kino, M., Matsumura, T., Gamo, M., and Saito, K. (1982)Biomed. Mass Spectrom. 9, 363–369.
Constantin, E., Nakatani, Y., and Hueber, R. (1980)Tetrahedron Let. 21, 4745–4746.
Wood, G.W., Morrow, G., Rao, G., Schmidt, D.E., and Tuebner, J. (1977)Chem. Phys. Lipids 18, 316–333.
Bose, A.J., Fujwara, H., Pramanik, B.N., Lazarro, E., and Spillert, C.R. (1978)Anal. Biochem. 89, 294–291.
Crawford, C.G., and Plattner, R.D. (1984)J. Lipid Res. 25, 518–522.
Barber, M., Bordeli, R.S., Sedwick, R.D., and Tyler, A.M. (1981)J. Chem. Soc., Chem. Commun. 325–327.
Chilton, F.H., and Murphy, R.C. (1986)Biomed. Environ. Mass Spectrom. 13, 71–76.
Jensen, N.J., Tomer, K.B., and Gross, M.L. (1986)Lipids 21, 580–588.
Haroldsen, P.E., and Gaskell, S.J. (1989)Biomed. Environ. Mass Spectrom. 18, 439–444.
Munster, H., and Budzikiewicz, H. (1988)Biol. Chem. Hoppe-Seyler 369, 303–308.
Author information
Authors and Affiliations
About this article
Cite this article
Zirrolli, J.A., Clay, K.L. & Murphy, R.C. Tandem mass spectrometry of negative ions from choline phospholipid molecular species related to platelet activating factor. Lipids 26, 1112–1116 (1991). https://doi.org/10.1007/BF02536512
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02536512