LC-MS/MS (liquid chromatography-tandem mass spectrometry) fatty acid efficient identification, screening and analysis method based on parallel labeling derivatization

The invention belongs to the technical field of biochemical analysis, and discloses an LC-MS/MS (liquid chromatography-tandem mass spectrometry) fatty acid efficient identification, screening and analysis method based on parallel labeling derivatization. According to the method, a derivatization reagent dansylhydrazide (DnsHz) is adopted, light/heavy isotope labeling derivatization reagents DnsHz and d6-DnsHz are adopted to perform derivatization reaction on a to-be-detected sample respectively, and a pair of light/heavy isotope labeling derivatization products with the same functional groups are obtained. And carrying out identification and structural identification on unknown fatty acid in the labeled derivatized sample to be detected through LC-MS/MS analysis. According to the invention, simultaneous online analysis of short-chain, medium-chain and long-chain fatty acids and high-sensitivity and high-coverage recognition and analysis of fatty acid metabolites in complex plasma samples are realized, and int