Abstract

DEVELOPMENT OF ENANTIO-SELECTIVE REVERSE PHASE CAPILLARY ELECTROPHORESIS DIRECT SEPARATION METHOD FOR THE DETERMINATION OF VALACYCLOVIR D - ISOMER

Pavani Jagu*, Aparna Kottimbakam, Dr. B.M. Rao, Dr. Basavaiah . K, Dr. Girish R Deshpande and D. Ramadevi

Abstract

An accurate and reproducible capillary electrophoresis (CE) method has been developed and validated for the direct separation of individual enantiomers of valacyclovir, the active anti-viral drug. The enantiomers were resolved by reverse phase chromatography, on an extended light path bare fused silica capillary using 30 mM potassium hydrogen phosphate (KH2PO4), at pH = 2.5 ± 0.1 as background electrolyte. Baseline separation of the enantiomers of valacyclovir was obtained with a profound resolution of greater than 7.0. The developed method was extensively validated and proved its suitability and robustness. The standard curve for (D) - valacyclovir was linear (r > 0.999) in the concentration range from 0.25 μg mL-1 (LOQ) to 30 μg mL-1 for an analyte concentration of 0.5 mg mL-1. The percentage recovery of (D) - valacyclovir was ranged from 89.753 to 102.273 in bulk drug samples of valacyclovir. The limit of detection and limit of quantitation of (D) – valacyclovir is found to be 0.084 μg mL-1 and 0.25 μg mL-1 respectively. The relative standard deviation of method precision and intermediate precision for the area % of (D) - valacyclovir is observed to be 2.4 and 2.6 respectively. valacyclovir sample solution stability and mobile-phase stability were studied for 48 h and found to be stable during the period. The validated method yielded good results of selectivity, linearity, precision, accuracy and robustness. The method was also able to resolve the enantiomers from the degradation impurities of valacyclovir.

Keywords: Valacyclovir, Capillary Electrophoresis, Extended light path bare fused-silica capillary, Method validation.