DETERMINATION OF THROMBOXANE-B2 BY NORMAL-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY AFTER PRECOLUMN DERIVATIZATION WITH FLUORESCENT REAGENTS

Thromboxane B2 (TxB2) was determined by high performance liquid chroma tography (HPLC) after pre-column derivatization with fluorescent probe s. We report the results of two derivatization procedures. The carboxy lic group of thromboxane B2 was esterified either by 4-bromomethyl-7-m ethoxycoumarin or by panacyl bromide whereas its alcoholic functions w ere derivatized using 7-[(chlorocarbonyl) methoxyl-4 methylcoumarin. C haracteristics of the method and first results with TxB2 released by p latelets under pharmacological stimulation are reported.The fluorescen t esters obtained were chromatographed on a normal phase column (LiChr osorb Diol 5 mum) with hexane-ethanol (80 : 20, v/v or 90 : 10, v/v) a nd detected by fluorescence. This method was applied to the determinat ion of TxB2 produced in vitro by human platelets under stimulation by pharmacological agents.