Analytical method development and validation for simultaneous estimation of lopinavir and ritonavir by RP-HPLC.

ABSTRACT

A simple, precise, rapid, selective, and economic reverse phase high performance liquid chromatographic (RP-HPLC) method has been developed for the simultaneous estimation of Lopinavir and Ritonavir in marketed formulations. Chromatographic separation was achieved isocratically for the combination was done with a C18 column [ ODS UG column. 250mm× 4.5 mm] utilizing mobile phase of composition Acetonitrile and Phosphate buffer (6040v/v, pH 3) the flow rate was 1.5ml/min and the eluates was monitored at 220nm. Lopinavir and Ritonavir were eluted with retention times of 2.1min and 4.0min respectively. The method was found to be linear over a range of 20-100 μg/ml for Lopinavir and Ritonavir. The method was validated according to the guidelines of International Conference on Harmonisation (ICH) and was successfully employed in the estimation of commercial formulations.