Improving lipidomic coverage for animal matrices by optimizing extraction methods and resuspension solvents based on UHPLC-Q-Exactive Orbitrap MS/MS.

Due to the complexity of animal matrices and the different polarities of lipids, the measurement methods are expected to cover a comprehensive range of lipid species. Three extraction methods (chloroform/methanol, methyl tert-butyl ether, and Soxhlet methods) and three resuspension solvents (methanol, isopropanol/acetonitrile = 1:1, and isopropanol/acetonitrile = 9:1) were used to compare the lipid species, contents, and ionization efficiency of Spanish mackerel and duck muscles. Overall, the chloroform/methanol extraction method was the most effective in capturing a diverse array of lipid species. The redissolution solvent isopropanol/acetonitrile (1,1) was highly efficient for detecting triglycerides, while methanol was effective in detecting diacylglycerols and phospholipids. Optimizing the measurement conditions of lipids with different polarities provides a valuable reference for lipid extraction and structural elucidation in different muscle tissues. Furthermore, it supports the determination of differential markers for animal lipid metabolism studies or food authentication using an untargeted lipidomic approach.