STABILITY INDICATING RP-HPLC METHOD FOR THE SIMULTANEOUS DETERMINATION OF ENIITRICITABINE, TENOFOVIR, COBICISTAT AND ELVITEGRAVIR

A stability-indicating RP-HPLC method for the simultaneous deteimination of emtricitabine (EMT), tenofovir (TNF), cobicistat (COB) and elvitegravir (ELV) in solid dosage forms. The waters 2695, High-Performance Liquid Chromatographic system with column kromasil C15, 250 x 4.6 mm, 5 t. The detector used is PDA detector at 288 nm. The mobile phase used in this method is pH-3.5 phosphate buffer and acetonitrile in the ratio of 60:40% V/V. Flow rate used for this proposed method is 1.0 ml/min. The retention times observed are 2.304 min, 2.691 min, 3.185 min and 4.537 min for emtricitabine, tenofovir, cobicistat, and elvitegravir respectively. The linearity calculated was found to be within the range. The % recoveries for EMT, TNF, COB and ELV were within the acceptance criteria. These drugs were found to be stable at forced degradation studies and results are within the limits. The proposed method can be used for the quality control of the combination in the pharmaceutical dosage forms.