Analysis of Triacylglycerol by Frit-FAB/LCMS

Abstract

LC/MS analysis of triacylglycerols was carried out by cationization using Frit-FAB interface. Conventional triacylglycerol analysis utilizes m-NBA as the FAB matrix. However, by using methanol as the mobile phase for separating triacylglycerols, a glycerol matrix could also be applied. Through cationization in glycerol matrix containing 3 mM NaI, the molecular weight of triacylglycerol could be determined from [M+Na]⁺ ions, similar to using a m-NBA matrix. Furthermore, the fatty acid compositions of triacylglycerols could be determined from [M-(RCOO)]⁺ fragment ions. Additionally, dipalmitoyl-oleoyl-glycerol stereoisomers were separated with a C₃₀ column by the slot model effect, the different mass spectra of 1,3-dipalmitoyl-2-oleoyl-sn-glycerol and 1,2-dipalmitoyl-3-oleoyl-rac-glycerol were determined.