Simultaneous determination of disulfiram and bupropion in human plasma of alcohol and nicotine abusers

An isocratic high-performance liquid-chromatographic method has been developed for the simultaneous determination of disulfiram and bupropion in human plasma samples. Analyses were carried out on a C(8) reversed-phase column using a mobile phase composed of 50% acetonitrile and 50% aqueous phosphate buffer, containing triethylamine. Diode-array detection was used, operating at a wavelength of 250 nm. For the clean-up of plasma samples, a solid phase extraction procedure, based on C(2) cartridges, was implemented. Extraction yields of the analytes were satisfactory, being always higher than 84%. The calibration curve was linear over the 5-500 ng mL(-1) plasma concentration range for both disulfiram and bupropion. The method showed a high sensitivity (limit of detection of 1.5 ng mL(-1)) and satisfactory precision, selectivity and accuracy. The application to human plasma samples obtained from some alcohol and nicotine abusers also gave good results.