Two simple, precise and economical UV methods have been developed for the simultaneous estimation of Lopinavir and Ritonavir in bulk and pharmaceutical dosage form. Method A is Absorbance maxima method, which is based on measurement of absorption at maximum wavelength of 238 nm and 260 nm for Ritonavir and Lopinavir respectively. Method B is area under curve (AUC), in the wavelength range of 228-248 nm for Ritonavir and 250- 270 nm for Lopinavir. Linearity for detector response was observed in the concentration range of 10-35μg/ml for Ritonavir and 100-500 μg/ml for Lopinavir. The accuracy of the methods was assessed by recovery studies and was found to be 99.64 % and 98.97% for Ritonavir and Lopinavir. The developed method was validated with respect to linearity, accuracy (recovery), precision and specificity. The results were validated statistically as per ICH Q2 R1 guideline and were found to be satisfactory. The proposed methods were successfully applied for the determination of for Ritonavir and Lopinavir in commercial pharmaceutical dosage form.
