title: Targeted lipidomics using electron capture atmospheric pressure chemical ionization mass spectrometry.
abstract: There is an increasing need to be able to conduct quantitative lipidomics analyses as a complement to proteomics studies. The highest specificity for proteomics analysis can be obtained using methodology based on electrospray ionization (ESI) or atmospheric pressure chemical ionization (APCI) coupled with liquid chromatography/tandem mass spectrometry (LC/MS/MS). For lipidomics analysis it is often necessary to be able to separate enantiomers and regioisomers. This can be very challenging when using methodology based on conventional reversed-phase chromatography. Normal-phase chromatography using chiral columns can provide dramatic improvements in the resolution of enantiomers and regioisomers. However, conventional ESI- and APCI-MS/MS has limited sensitivity, which makes it difficult to conduct studies in cell culture systems where only trace amounts of non-esterified bioactive lipids are present. The use of electron capture APCI-MS/MS overcomes this problem. Enantiomers and regioisomers of diverse bioactive lipids can be quantified using stable isotope dilution methodology coupled with normal-phase chiral chromatography and electron capture APCI-MS/MS. This methodology has allowed a lipidomics profile from rat epithelial cells maintained in culture to be delineated and allowed the effect of a non-selective lipoxygenase inhibitor to be assessed.
mesh_terms: D000818:Animals; D001274:Atmospheric Pressure; D006893:Hydroxyeicosatetraenoic Acids / Q000032:analysis / Q000737:chemistry; D007422:Intestines / Q000737:chemistry / Q000166:cytology; D008041:Linoleic Acids / Q000032:analysis / Q000737:chemistry; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis* / Q000737:chemistry*; D015394:Molecular Structure; D011453:Prostaglandins / Q000032:analysis / Q000737:chemistry; D051381:Rats; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D006893:Hydroxyeicosatetraenoic Acids; D008041:Linoleic Acids; D008055:Lipids; D011453:Prostaglandins