Multistage tandem mass spectrometry of anionic phosphatidylcholine lipid adducts reveals novel dissociation pathways

Abstract

The gas-phase fragmentation reactions of various anionic adducts of phosphatidylcholine lipids have been examined by electrospray ionization and multistage tandem mass spectrometry (MSn) in a linear quadrupole ion trap mass spectrometer. The MS/MS and MSn fragmentation reactions of the anionic adducts were found to be highly dependent on the identity of the anions (A). Consistent with previous reports, MS/MS of phosphatidylcholine lipid ions formed by anionic adduction with formate, acetate and chloride resulted in a dominant product ion corresponding to the loss of (A + CH3) from the [M + A]- precursor ions. In contrast, MS/MS of other anion adducted precursor ions gave rise to multiple pro..