出版社:American Society for Biochemistry and Molecular Biology
摘要:We describe an improved assay for platelet-activating factor (PAF; 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) using HPLC-tandem mass spectrometry (LC-MS/MS). The present method can readily detect as little as 1 pg (1.9 fmol) of PAF, a significant improvement over previously described LC-MS/MS methods, and gives a linear response up to 1,000 pg of PAF. Our method also overcomes the artifacts from isobaric lipids that have limited the usefulness of certain existing LC-MS/MS assays for PAF. In the course of these studies, we detected three novel lipid species in human neutrophils. One of the novel lipids appears to be a new molecular species of PAF, and the other two have chromatographic and mass spectrometric properties consistent with stearoyl-formyl-glycerophosphocholine and oleoyl-formyl-glycerophosphocholine.
These observations identify previously unknown potential interferences in the measurement of PAF by LC-MS/MS. Moreover, our data suggest that the previously described palmitoyl-formyl-glycerophosphocholine is not unique but rather is a member of a new and poorly understood family of formylated lipids.
Abbreviations: d3-16:0 PAF, 1-O-hexadecyl-2-[2H3]acetyl-glycerophosphocholine; fMLP, N-formyl-methionyl-leucyl-phenylalanine; GPC, sn-3-glycerophosphocholine; LC-MS, high-performance liquid chromatography-mass spectrometry; LC-MS/MS, high-performance liquid chromatography-tandem mass spectrometry; lysoPC, lysophosphatidylcholine; MRM, multiple reaction monitoring; PAF, platelet-activating factor; PFPC, palmitoyl-formyl-glycerophosphocholine; PMN, polymorphonuclear neutrophil
关键词:high-performance liquid chromatography tandem mass spectrometry • trace analysis • neutrophil