ANALYSIS OF COCAINE, BENZOYLECGONINE, AND COCAETHYLENE IN URINE BY HPLC WITH DIODE-ARRAY DETECTION

A solid phase extraction method was developed for the isolation of coc aine, benzoylecgonine, and cocaethylene from urine followed by high-pe rformance liquid chromatography/diode array detection. The application of a new solid hybrid phase extraction technology produced much clean er extracts than conventional extraction procedures and made the selec tive extraction of substances with different polarities possible. Two internal standards with great structural resemblance to benzoylecgonin e (a carboxylic acid) and to the two esters, cocaine and cocaethylene, respectively, were synthesized. A linear response over a broad concen tration range was obtained. The sensitivity, specificity, and accuracy were satisfactory for each analyte. Hydrolysis of cocaine and cocaeth ylene to benzoylecgonine during extraction and analysis was less than 0.5%, The method described can be used to corroborate cocaine use, to establish cocaine overdoses, and to study pharmacological effects of c ocaine and its metabolites.