Stereoselective determination of benalaxyl in plasma by chiral high‐performance liquid chromatography with diode array detector and application to pharmacokinetic study in rabbits

Abstract A chiral high‐performance liquid chromatography method with diode array detector was developed and validated for stereoselective determination of benalaxyl (BX) in rabbit plasma. Good separation was achieved at 20°C using cellulose tris‐(3,5‐dimethylphenylcarbamate) as chiral stationary phase, a mixture of n ‐hexane and 2‐propanol (97:3) as mobile phase at a flow rate of 1.0 ml/min. The assay method was linear over a range of concentrations (0.25–25 μg/ml) in plasma and the mean recovery was greater than 90% for both enantiomers. The limits of quantification and detection for both enantiomers in plasma were 0.25 and 0.1 μg/ml, respectively. Intra‐ and interday relative standard deviations (RSDs) did not exceed 10% for three‐tested concentrations. The method was successfully applied to pharmacokinetic studies of BX enantiomers in rabbits. The result suggested that the pharmacokinetics of BX enantiomers was stereoselective in rabbits. Chirality, 2006. © 2006 Wiley‐Liss, Inc.