Notice of Retraction Direct Chiral Resolution and Determination of Enantiomeric Ratio of Lambda-Cyhalothrin in Rabbits by High-Performance Liquid Chromatography

ChirsA pesticides currently constitute about 50% of all pesticides dosage used in China, and this ratio is increasing as more complex structres compouds are introduced into use. Lambda-cyhalothrin (LCT) is a chiral insecticide consisting of a pair of enantiomers. The enantioselectivity separation of lambda-cyhalothrin was studied on cellulose tris-(3, 5-dimethylphenylcarbamate)-coated chiral stationary phase (CDMPC-CSP) using normal phase high-performance liquid chromatography (NP-HPLC). The effects of the mobile phase composition, flow rate and column temperature on enantiomers separation were determined. A chiral high-performance liquid chromatography method was developed and validated for stereoselective determination of lambda-cyhalothrin in rabbits. The results showed that good separation was achieved at 25°C using cellulose tris-(3, 5-dimethylphenylcarbamate) as chiral stationary phase, a mixture of n-hexane and iso-propanol (92:8) as mobile phase at a flow rate of 1.0 ml/min. The assay method was linear over a range of concentrations (0.1-50 μg/ml) in plasma and the mean recovery was greater than 80% for both enantiomers. The limits of detection for both enantiomers in plasma were 0.1 μg/ml. Intraand interday coefficient of variation (CVs) did not exceed 15% for three-tested concentrations. The method was successfully applied to determination enantiomer ratio (ER) of LCT in rabbits. The result suggested that the degradation of LCT enantiomers was stereoselective in rabbits.