Abstract:Objective: To establish a capillary electrophoresis method for the separation and determination of chlorobenzyltetrahydroberberine (CBTHB)enantiomers and to investigate their chiral pharmacokinetics in rabbits. Methods: Racemic CBTHB was separated optimally and measured successfully by capillary electrophoresis, based on comparison of chiral recognition capabilities of carboxymethylated cyclodextrins and selection of other electrophoretic conditions.The plasma concentration data were handled with theory of statistical moment and the pharmacokinetic parameters were obtained. Results: CBTHB enantiomers in rabbit plasma samples were separated under optimal chiral conditions. After a single oral dose of 150 mg/kg racemic CBTHB in six rabbits, plasma level of R-enantiomer was always higher than that of S-enantiomer. The ratio of R-to S-enantiomer was (1.43±0.21), resulting in more significant differences between the plasma concentrations of R-enantiomer and those of S-enantiomer(t = 4.14,P<0.01). Furthermore, it was found that AUC0?τ and AUC0?∞ of R-enantiomer were significantly greater than those of S-enantiomer. Conclusion:The new chiral capillary electrophoresis method proves to be suitable for studies on CBTHB enantiomers pharmacokinetics.