Endogenous ethanolamide analysis in human plasma using HPLC tandem MS with electrospray ionization.

A sensitive and selective liquid chromatography tandem mass spectrometry (LC\MS\MS) method has been developed for the simultaneous quantification in human plasma of the endocannabinoid anandamide (AEA) and three other related ethanolamides, linoleoyl ethanolamide (LEA), oleoyl ethanolamide (OEA), and palmitoyl ethanolamide (PEA). The analytical methodology requires 50 microL of human plasma which is processed via protein precipitation using a 96-well protein precipitation plate. Chromatographic separation of plasma extract was achieved with a Phenomenex Gemini C6-Phenyl HPLC column (2.