For the extraction of plasma lipids we used a very rapid and efficient method.
To 0.2 ml plasma add 0.3 ml 0.5 M KH2PO4 , 1.5 ml chloroform and 0.5 ml methanol. After vortexing 2 minutes and centrifugation, the lower phase is collected with a Pasteur pipette through the protein disk and evaporated.
A procedure using the detergent Triton X-114 was shown to be very efficient for the extraction of plasma lipids, while sparing the protein fraction for further use (Ferraz TPL et al., J Biochem Biophys Meth 2004, 58, 187).
A method based on the modification of an extraction method originally developed for pesticide residue analysis in food has been described for the purpose of isolating lipids from biological fluids (plasma, urine) (Bang DY et al., J Chromatogr A 2014, 1331, 19). The procedure adapted for the preparation of samples for mass speectrometry includes a extraction/partitioning step with a mixture of CHCl3/CH3OH in the presence of MgSO4 and CH3COONa and an adsorption/desorption step with C18 particles. That method was applied to lipid extracts from both human urine and plasma samples, demonstrating that it can be powerfullyutilized for high-speed (<15 min) preparation of lipids compared to the Folch method, with equivalent or slightly improved results in lipid identification using liquid chromatography and mass spectrometry.