DETERMINATION OF ILLICIT DRUGS AND RELATED SUBSTANCES BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH AN ELECTROCHEMICAL COULOMETRIC-ARRAY DETECTOR

A general method for the simultaneous determination of fifteen common drugs (6-acetylmorphine, 3,4-methylenedioxymetamphetamine, buprenorphi n, cocaine, codeine, dihydrocodeine, ethylmorphine, heroin, hydrocodon e, lidocaine, methadone, morphine, naloxone, procaine and thebaine) wa s developed using reversed-phase HPLC and electrochemical detection. T he separation of the drugs was achieved by using as the mobile phase 2 0 mM monobasic sodium phosphate-acetonitrile (90:10) with a gradient t o 50% of the organic modifier, on a silica based C-18 column (150 x 4. 6 mm I.D.) of 3 mu m particle size and by the selectivity supplied by an array of eight coulometric electrodes at increasing potential. It w as possible to identify and to determine fifteen different drugs in th e same chromatographic run in 50 min. The method was tentatively appli ed to the determination of drugs in extracts of human hair.