Fig. 4.
A: Extracted ion chromatograms obtained by LC/MS phospholipid profiling of bovine liver samples. Lipids were extracted by BD and 3PLE. PG(34:1) and PI(36:2) are two endogenous phospholipid species identified in the matrix. PA(15:0/18:1{2H7}) and PS(15:0/18:1{2H7}) are two phospholipid standards spiked in the samples prior to the lipid extraction. The represented data were acquired in the negative ionization mode. B: Total ion chromatogram and product ion mass spectra of PC(34:2) obtained by direct-infusion MS/MSall in the positive ionization mode. The bovine liver lipids were extracted by BD and 3PLE. PA, phosphatidic acid;PG, phosphatidylglycerol; PI, phosphatidylinositol; PS, phosphatidylinositol.