Eicosanoids are lipid mediators generated from arachidonic acid with pro- and anti-inflammatory properties. Despite these lipid mediators being known for decades, quantitative determination in biological samples is still challenging due to low abundance, instability, the existence of regio- and stereoisomers, and a wide polarity range that hampers chromatographic separation. In this study, we developed a supercritical fluid chromatography mass spectrometry (SFC-MS) platform for the quantification of relevant eicosanoids. Application of a chiral amylose-based column and modifier combination of 2-propanol/acetonitrile offered separation and sufficient resolution of 11 eicosanoids (5-, 12-, 15-HETE, PGB1, LTB4, t-LTB4, 20-OH-LTB4, PGE2, PGD2, PGF2α, TxB2) with baseline separation of isobaric analytes within 12 min. The method was validated in terms of range (78-2500 ng/mL), linearity, accuracy, precision, and recovery according to EMA guidelines. Finally, we confirmed the method's applicability by quantifying eicosanoid levels in human primary blood cells. In conclusion, we present a validated SFC-MS method for the determination of relevant eicosanoids in biological samples with a wide range of polarity while maintaining baseline separation of isobars, which allows coupling to a single quadrupole mass detector.
Keywords: lipid mediators; monocytes; neutrophils; oxylipins; platelets; supercritical fluid chromatography; validation.