Fatty Acid Composition by Total Acyl Lipid Collision-Induced Dissociation Time-of-Flight (TAL-CID-TOF) Mass Spectrometry.

Total acyl lipid collision-induced dissociation time-of-flight (TAL-CID-TOF) mass spectrometry uses a quadrupole time-of-flight (QTOF) mass spectrometer to rapidly provide a comprehensive fatty acid composition of a biological lipid extract. Samples are infused into a QTOF instrument, operated in negative mode, and the quadrupole is used to transfer all, or a wide mass range of, precursor ions to the collision cell for fragmentation. Time-of-flight-acquired mass spectra provide mass accuracy and resolution sufficient for chemical formula determination of fatty acids in the complex mixture. Considering the limited number of reasonable CHO variants in fatty acids, one can discern acyl anions with the same nominal mass but different chemical formulas. An online application, LipidomeDB Data Calculation Environment, is employed to process the mass spectral output data and match identified fragments to target fragments at a resolution specified by the user. TAL-CID-TOF methodology is a useful discovery or screening tool to identify and compare fatty acid profiles of biological samples.