RP-HPLC Method Development and Validation for Simultaneous Estimation of Lopinavir and Ritonavir in Dosage form and in Plasma
A simple, selective, rapid, precise and economical reverse phase high performance liquid chromatographic (RP- HPLC) method has been developed for the simultaneous estimation of Ritonavir and Lopinavir in pharmaceutical dosage form and in plasma. The method was carried out on reverse- phase C18 column, with mixture of methanol: water (85:15v/v) was used as a mobile phase and the pH was adjusted to 3.5 by using O- phosphoric acid, at 1ml/min flow rate. Different analytical parameters such as linearity, precision, accuracy, limit of detection (LOD), limit of quantification (LOQ), robustness were determined according to International Conference on Harmonization (ICH) guidelines. . The linear regression analysis data for the linearity plot showed good linear relationship with correlation coefficient value for Ritonavir and Lopinavir were r2=0.9998 and r2=0.9994 in the concentration range of 5-50 μg/ml, 20-200 μg/ ml respectively. Retention times of Ritonavir and Lopinavir were 4.8min and 5.9min.The described HPLC method showed to be sensitive for simultaneous determination of Ritonavir and Lopinavir with regard to the LOD and LOQ values. This method had been extensively validated. These methods allow a number of cost and time saving benefits. The described methods can be readily utilized for the analysis of pharmaceutical preparations.