ANALYSIS OF THE EICOSAPENTAENOIC ACID (EPA) METABOLITE DEL-17-6-KETO-PGF1-ALPHA IN HUMAN PLASMA BY GC/SIM USING [O-18]DELTA-17-6-KETO-PGF1-ALPHA

A method of the microdetermination of DELTA17-6-keto-PGF1alpha, a hydrolyzed metabolite of PGI3, is described. An authentic DELTA17-6-keto-PGF1alpha (120 mg) was prepared from eicosapentaenoic acid (EPA) incubated with homogenate of bovine aortic intima. [O-18]DELTA17-6-Keto-PGF1alpha was synthesized by repeating base-catalyzed hydrolysis of methyl ester derivatives in [O-18] water, to obtain an internal standard in gas chromatography/selected ion monitoring (GC/SIM) of DELTA17-6-keto-PGF1alpha. Good linear response over the range of 10 pg-10 ng was demonstrated. Chromatographic conditions using a MP-65HT column presented nearly baseline separation of DELTA17-6-keto-PGF1alpha and 6-keto-PGF1alpha. We were able to detect DELTA17-6-keto-PGF1alpha in the range from 6 to 26 pg/ml of the human plasma. The present method can be applied to the determination of DELTA17-6-keto-PGF1alpha in the human urine and plasma.