METHOD DEVELOPMENT AND VALIDATION OF STABILITY INDICATING RP-HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF RITONAVIR AND LOPINAVIR IN PURE AND PHARMACEUTICAL DOSAGE FORM

A simple, accurate, precise method was developed for the simultaneous estimation of the ritonavir and lopinavir in tablet dosage form. Chromatogram was run through Std ODS 250mm x 4.6 mm, 5m. Mobile phase containing buffer and acetonitrile in the ratio of 60:40A was pumped through column at a flow rate of 1ml/min. Buffer used in this method was 0.02N KH2PO4 buffer at pH 4.6. Temperature was maintained at 30°C. Optimized wavelength for ritonavir and lopinavir was 250 nm. Retention time of ritonavir and lopinavir were found to be 2.27min and 3.74min. %RSD of the ritonavir and lopinavir were and found to be 0.46 and 0.37 respectively. % Recover was obtained as 99.91 to 100.14 for Ritonavir and 99.78 to 100.06 for lopinavir respectively. LOD, LOQ values are obtained from regression equations of ritonavir and lopinavir were 0.25ppm, 0.74ppm, 0.50ppm and 1.51ppm respectively. Regression equation of ritonavir and lopinavir y = 10321x + 767.6 and y = 3625x + 545.7