Measurement of plasma prostaglandin E2 using capillary gas chromatography negative ion chemical ionization mass spectrometry.

A stable isotope dilution assay for the measurement of plasma prostaglandin E2 (PGE2) employing capillary column gas chromatography-negative ion chemical ionization mass spectrometry (GC-NICIMS) is described. PGE2 was extracted from plasma using C18 and silica SEP-PAKS. Further purification and separation was accomplished by thin layer chromatography. The prostaglandin was analyzed as its pentafluorobenzyl ester-methoxime-trimethyl-silyl ether, using fragment ions at m/e 524 (protium) and m/e 528 (deuterium) for quantitation. The mean plasma concentration of PGE2 determined in 8 healthy volunteers was 2.8 +/- 2.0 pg/ml.