Simultaneous determiantion of thioTEPA,TEPA and a novel, recently identified thioTEPA metabolite,mnochloroTEPA, in urine using capillary gas chromatography

摘要

An as~ay for the simultaneou~ quantitative determination of thioTEPA, TEPA and the recently identified metabolite N,N'-diethylene-N"-2-chloroethylphosphoramide (monochloroTEPA) in human' urine has been developed. MonochloroTEPA was synthesized by incubation of TEPA with sodium chloride at pH 8. Thus, with this assay monochloroTEPA is quantified as TEPA equivalents. Analysis of the three analytes in urine was performed using ga~ chromatography with selective nitrogen~phosphorous detection after extraction with a mixture of 1-propanol and chloroform from urine samples. Diphenylamine was used as inte!llal standard. Recoveries ranged between 70 and ]00% and both accuracy and precision were 1ess than 15%. Linearity was accomplished in the range of 25-2500 ng/rn1 for monochloroTEPA and 25-5000 ng/ml for thioTEPA and TEPA. Monoc~loroTEPAproved to be stable in urine for at least 4 weeks at -80°C: ThioTEPA, TEPA and monochloroTEPA cummulative urInary excretion from two patients treated with thioTEPA are presented demonstrating the applicability of the assay for clinical sample~ and that the excreted amount of monochloroTEPA exceeded that of thioTEPA on ~~y Z to 5 of urine collection.