Simultaneous Determination of Ritonavir and Lopinavir in Combined Tablet Dosage Form by HPTLC Method

A new, simple, sensitive, precise and accurate High-Performance Thin-Layer Chromatographic Method for simultaneousdetermination of Ritonavir (RTV) and Lopinavir (LPV) in their combined tablet dosage form has been developed, validatedand used for the determination of the compounds in commercial pharmaceutical products. Chromatographic separation wasachieved on aluminium plates pre-coated with silica gel 60 F254 as the stationary phase and toluene: ethyl acetate: methanol:glacial acetic acid (7:2:0.5:0.5, v/v/v/v) as the mobile phase. Densitometric measurements of their spots were achieved at 210nm over the concentration range of 400-2400 ng spot-1 and 1600-9600 ng spot-1, with mean recoveries of 99.78 ± 2.22 and98.40 ± 0.92 for Ritonavir and Lopinavir respectively. This method is simple, precise, and sensitive, and it is applicable forthe simultaneous determination of RTV and LPV in pure powder and in tablet formulation.