Method development, degradation pathway and kinetic of capecitabine

The present work describes a simple, accurate and precise Stability indicating RP-HPLC method for the estimation of Capecitabine (CPT) in bulk and pharmaceutical formulation. The Mobile phase used was Acetonitrile: Water (60: 40v/v) with 1ml/min. flow rate and 240nm was used as a wavelength maximum. The C18 HS (250 X 4.6) mm, 5 μm column was used as a stationary phase. The method was validated as per the ICHQ2 Guidelines. The retention time of CPT was found to be 3.3 min. A linear response was observed in the range of 10-50 μg/mL with a regression coefficient of 0.999. The LOD and LOQ were found to be 1.43μg/mL and 4.34μg/mL respectively. This method can be used for the determination of CPT in quality control of API and dosage form without interference of the excipients, impurities and degradation products and hence can be used as stability indicating assay method. CPT was subjected to degradation under different stress conditions recommended by ICH viz acid, alkali, photolytic, dry heat and oxidative condition. The samples so generated were used for degradation studies including degradation kinetic study using the developed method. The degradation pathway of CPT was found to be acid hydrolysis and temperature exceeding 100°c. The degradation kinetic study shows that the acid hydrolysis, alkaline hydrolysis and oxidative degradation of the CPT follow first order kinetic.