A Validated Reverse Phase HPLC Method for the Simultaneous Estimation of Ritonavir and Lopinavir in Pharmaceutical Dosage Forms

A simple, sensitive and precise reverse phase high performance liquid chromatographic method has been developed for the simultaneous estimation of Ritonavir and Lopinavir in pharmaceutical dosage forms. The mobile phase consisted of Acetonitrile: buffer (0.05 M Potassium dihydrogen orthophosphate, P^H-3) in the ratio of 50:50 v/v delivered at a flow rate of 2.0 ml/min and wavelength of detection at 215 nm. The retention times of Ritonavir and Lopinavir were 10.253 min and 12.490 min respectively. The developed method was validated according to ICH guidelines. The proposed method can be used for determination of these drugs in combined dosage forms.