SIMULTANEOUS DETERMINATION OF COCAETHYLENE AND COCAINE IN BLOOD BY GAS-CHROMATOGRAPHY WITH SURFACE-IONIZATION DETECTION

Cocaethylene together with cocaine spiked in human whole blood has bee n found measurable at high sensitivities by capillary gas chromatograp hy with surface ionization detection. The drugs could be rapidly extra cted by Sep-Pak C-18 cartridges with recovery of more than 60 %. The c alibration curves for both cocaethylene and cocaine using cocapropylen e as internal standard were linear in the range 50-300 pmol mL(-1) of whole blood. The detection limits of cocaethylene and cocaine were 5-1 0 pmol mL(-1) (0.1-0.2 pmol on column if recovery is 100 %). Cocaethyl ene could be determined for whole blood obtained from rats (ca. 200 g body wt.), which had received subcutaneous injection of 10 mg cocaine hydrochloride and 2.0 mL of 30 % (v/v) ethanol 3 h before sampling; th e mean levels of cocaethylene and cocaine were 101 and 1230 pmol mL(-1 ), respectively.