RP-HPLC METHOD FOR SIMULTANEOUS DETERMINATION OF EMTRICITABINE, RILPIVIRINE AND TENOFOVIR EMPLOYING RESPONSE SURFACE DESIGN T.Sudha

A high performance liquid chromatographic method has been developed and optimized for the simultaneous determination of emtricitabine, rilpivirine and tenofovir in bulk and in tablet dosage form. In this work, multiple response simultaneous optimization using Derringer’s desirability function was employed for the development. The ranges of three experimental factors used for the optimization were acetonitrile concentration (50 -60%), buffer pH (2.5-3.5) and flow rate (0.8-1.2ml/min). The influence of these independent variables on the output responses such as capacity factor of the first peak (k1), resolution (Rs 2,3) and retention time (Rt) were evaluated. The experimental responses were fitted into a second order polynomial equation. The optimized assay conditions were acetonitrile: phosphate buffer (69.7: 30.3%v/v) (pH 2.5) as the mobile phase and flow rate at 1.2 ml/min. While using this optimum condition, the total run time was less than 7 min were achieved. The optimized assay condition was validated according to ICH guidelines to confirm specificity, linearity accuracy and precision.