DETERMINATION OF SULFIDOPEPTIDE LEUKOTRIENES IN BIOLOGICAL-FLUIDS BY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

A fast, sensitive, and accurate assay for the quantitative determination of leukotrienes LTC//4, LTD//4, and LTE//4 in biological fluids by capillary gas chromatography and electron capture mass spectrometry has been developed. The assay is based upon the two-step reduction of these molecules using hydrogen and rhodium on alumina as catalyst to effect efficient saturation of the leukotriene double bonds followed by Birch reduction (lithium in methylamine) to complete thioester cleavage. The average yield of 5-hydroxyeicosanoic acid from these leukotrienes has been found to be 80 plus or minus 5% and 96 plus or minus 3% after the first and second step or reduction, respectively.