title: Quantitative analysis and molecular species fingerprinting of triacylglyceride molecular species directly from lipid extracts of biological samples by electrospray ionization tandem mass spectrometry.
abstract: Herein we describe a rapid, simple, and reliable method for the quantitative analysis and molecular species fingerprinting of triacylglycerides (TAG) directly from chloroform extracts of biological samples. Previous attempts at direct TAG quantitation by positive-ion electrospray ionization mass spectrometry (ESI/MS) were confounded by the presence of overlapping peaks from choline glycerophospholipids requiring chromatographic separation of lipid extracts prior to ESI/MS analyses. By exploiting the rapid loss of phosphocholine from choline glycerophospholipids, in conjunction with neutral-loss scanning for individual fatty acids, overlapping peaks in the ESI mass spectrum were deconvoluted generating a detailed molecular species fingerprint of individual TAG molecular species directly from chloroform extracts of biological samples. This method readily detects as little as 0.1 pmol of each TAG molecular species from chloroform extracts and is linear over a 1000-fold dynamic range. The sensitivity of individual TAG molecular species to ESI/MS/MS analyses correlated with the unsaturation index and inversely correlated with total aliphatic chain length of TAG. An algorithm was developed which identifies sensitivity factors, thereby allowing the rapid quantitation and molecular species fingerprinting of TAG molecular species directly from chloroform extracts of biological samples.
authors.affiliation: Division of Bioorganic Chemistry and Molecular Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110, USA. xianlin@pcg.wustl.edu
authors.forename: X
authors.initials: X
authors.lastname: Han
authors.forename: R W
authors.initials: RW
authors.lastname: Gross
mesh_terms: D000818:Animals; D008055:Lipids / Q000737:chemistry*; D008297:Male; D009206:Myocardium / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D014280:Triglycerides / Q000032:analysis* / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D008055:Lipids; D014280:Triglycerides