Development and Validation of a Specific RP-HPLC Method for Simultaneous Estimation of Anti-retroviral Drugs: Application to Nanoparticulate Formulation System

Abstract

Objective: A simple, accurate and economical reverse phase- high performance liquid chromatographic method has been developed for the simultaneous quantitative estimation of two anti-retro viral drugs, Etravirine and Elvitegravir in nanoparticulate formulations for the first time. This method is a novel analytical technique for the detection of the both the drugs concurrently, as there is no method available for their simultaneous quantification, to the best of our knowledge. Methods: Optimization and validation of the chromatographic conditions were completed according to the standard ICH guidelines. The separation was done on a C18 column (250 mm x 4.6mm, 5μm) using methanol and phosphate buffer of pH (5.6) as the mobile phase in the ratio 78:22 v/v at a flow rate of 1ml/min for a short run time of 13 min. The detection wavelength was 285nm and the column temperature was maintained at 32oC. Results: The developed method was linear over 10 to 160 μg/ml with a regression coefficient of 0.999 for each. The LOD values were 4.83 and 9.25 µg/ml while LOQ values were 14.63 and 28.01 µg/ml for etravirine and elvitegravir respectively. The recovery values obtained by etravirine and elvitegravir were between 97.6% and 100.8%. Conclusion: The method was specific, precise, fast and accurate with good inter and intra day precision. The method was also effectively employed for the characterization and simultaneous quantification of both drugs in nanoparticulate formulation.