New Approaches to Lipid Analyses of Lipoproteins and Cell Membranes

摘要: Conventional and capillary gas chromatography-mass spectrometry (GC/MS) was used to determine the molecular association positional distribution of fatty acids in diacylglycerols nitrogenous bases ceramides following their conversion tert-butyl dimethyl silyl (t-BDMS) ethers. The were generated from corresponding glycerophospholipids sphingomyelins by hydrolysis with phospholipase C original lipoproteins cell membranes or appropriate total lipid extracts thereof. abundant M-57 ion provided weights for both ceramides. abundance ratio ions due losses acyloxy radical (M-RCOO) position 1 2 indicated proportion reverse isomers saturated diacylglycerols. unsaturated could be similarly determined after reducing sample hydrogen (unsaturated species having higher carbon numbers) deuterium presence Wilkinson’s catalyst. alkylacyl alkenylacyl glycerols identified at m/e values [M-57], [acyl + 74], [RO 114] [R-CH=CHO 114]. long chain via intense CH3(CH2)n-(CH=CH)m-CH2O-t-BDMS CH3(CH2)n-(Ch=CH)m-CONHCH-Ch2O-t-BDMS. These methods are suitable work stable isotope-labelled phospholipids isotopes present sufficient excess least one neutral moieties species. assays usually do not require silver nitrate prefractionation can executed microgram range material.