Rapid analysis of benzoylecgonine, cocaine, and cocaethylene in urine, serum, and saliva by isocratic high-performance liquid chromatography with diode-array detection

An isocratic high-performance liquid-chromatographic (HPLC) procedure with diode-array detection has been developed for the determination of benzoylec gonine, cocaine, and cocaethylene in urine, serum, and saliva. After solid- phase extraction with mixed-mode extraction cartridges the three solutes ar e separated, in less than 20 min, by HPLC on a Supelcosil ABZ+ column with 17:83 (v/v) acetonitrile-0.04 M phosphate buffer, pH 2.3, as mobile phase. Unambiguous identification of the compounds was achieved by means of their retention times and UV spectra. Satisfactory resolution was obtained betwee n interfering compounds, benzoylecgonine, cocaine, and cocaethylene. This a nalytical procedure proved suitable for the determination of cocaine and it s metabolites in drug addicts' urine and saliva, and rabbit serum.