Abstract: Objective To develop a high-performance liquid chromatographic method for determination of ketamine and norketamine in blood and urine. Methods The compounds were extracted from blood or urine by liquid-liquid extraction using toluene after blood or urine was adjusted pH to 14.The extracts were analyzed by HPLC. Results Linear limits of ketamine and norketamine determination in blood ranged from 0.05 μg/mL to 10 μg/mL (R2﹥0.9993) and in urine ranged from 0.01 μg/mL to 200 μg/mL (R2﹥0.999 5). Limits of detection (LODs) for ketamine and norketamine were 0.006 μg/mL and 0.003 μg/mL (S/N≥3), respectively. The mean extraction recovery was over 82.4% and its coefficients of variation were less than 10.0% for ketamine and norketamine. Concentration-time curves and urinary drug velocity curves of ketamine norketamine were obtained by determinations of them in blood and urine in rat using the developed method. Conclusion The method is sensitive, simple, rapid and suitable for determination of ketamine and norketamine in blood and urine for toxicological and clinical pharmaceutical analysis.

Key words: analysis, high-performance liquid chromatography, ketamine, norketamine