Bio-analytical chiral chromatography method for the enantioselective separation of carbinoxamine maleate in human plasma

Abstract

Background: A selective chiral high-performance liquid chromatography (HPLC) method was developed and validated to separate and quantify the (d) and (l) carbinoxamine enantiomers in human plasma. Methods: Plasma samples were extracted by liquid-liquid extraction. The separation of carbinoxamine enantiomers and internal standard (IS, pargeverine hydrochloride) was achieved on an amylose tris(5-chloro-2-methylphenylcarbamate) column with a mobile phase of n-Hexane/isopropanol/ethanol/diethyl amine (850:75:75:0.1, v/v/v/v) at a flow rate of 0.8 mL/min. The ultraviolet (UV) detection wavelength was set at 220 nm. Results: Baseline separation of carbinoxamine enantiomers and IS, free from endogenous interferences, was achieved in less than 15 min. Ratio of peak area of each enantiomer to IS was used for quantification of plasma samples. Linear calibration curves were obtained over the range of 20–7500 g/mL in plasma for both enantiomers (R2 > 0.99). The mean extraction recoveries were 103.8 ± 1.5 and 94.5 ± 1.8 % for (d) and (l) enantiomers of carbinoxamine enantiomers and 96.35 % for IS from human plasma. The mean relative error (RE %) of accuracy and the mean relative standard deviation (RSD %) of intra-day and inter-day precision for both enantiomers were <10 %. Conclusions: The method was validated with accuracy, precision, recovery, and stability and can be used to determine the pharmacokinetics of carbinoxamine enantiomers in human plasma. [Figure not available: see fulltext.].