Development, Optimization, and Validation of a RP-HPLC Method with PDA Detection for the Concurrent Quantification of Emtricitabine, Tenofovir Alafenamide, and Dolutegravir in Both Bulk and Pharmaceutical Dosage Forms

A simple, quick, precise and accurate HPLC (reverse phase) approach has been designed and optimized using a chemometric
tool to estimate dolutegravir, emtricitabine and tenofovir alafenamide, respectively. A design of central composite was used to optimize the response surface. As a result of trial and error, the parameters such as rate of solvent flow, buffer pH, and methanol concentration in the solvent system were determined. System responsiveness was estimated using the optimization process’s capacity factor, resolution, and retention time. The separation was achieved by using a solvent system containing
58.90% methanol and 41.10 triethylamine buffer (4.56 pH) at the rate of flow of 0.8 mL per minute on a phenomenex carbon
(18) column (150.4 4.6 mm; I.D., 5) under optimal conditions. The duration of retention for emtricitabine was 2.91 minutes, for tenofovir alafenamide it was 6.114 minutes; and for dolutegravir it was 8.824 minutes. A correlation coefficient of 0.9998, 0.9997, and 0.9999 was determined for emtricitabine’s calibration curves from 40 to 200 g/mL, tenofovir alafenamide’s from 5 to 25 g/mL, and emtricitabine’s from 10 to 50 g/mL, respectively. This approach was effective in estimating the simultaneous doses of medications in commercial combination forms.