VALIDATED HPLC METHOD FOR SIMULTANEOUS QUANTITATION OF TADALAFIL AND DAPOXETINE HYDROCHLORIDE IN BULK DRUG AND FORMULATION

Abstract

HPLC method has been described for simultaneous determination of Tadalafil and Dapoxetine Hydrochloride in formulation. This method is based on HPLC separation of the two drugs on the Thermo Hypersil BDS–C18 (250 mm × 4.6 mm, 5.0 µ) from Germany with isocratic conditions and simple mobile phase containing acetonitrile: 0.1 % triethyl amine in water pH adjusted to 4.0 with ortho phosphoric acid (80: 20) at flow rate of 1 mL/min using UV detection at 229 nm. This method has been applied to formulation without interference of excipients of formulation. The linear regression analysis data for the calibration plots showed a good linear relationship over the concentration range of 0.25-4 µg/mL for Tadalafil and 0.75-12 µg/mL for Dapoxetine Hydrochloride respectively. The mean values of the correlation coefficient, slope and intercept were 0.9995 ± 1.27, 133612 ± 0.72 and 49109 ± 1.21 for Tadalafil and 0.9992 ± 0.78, 155825 ± 0.87 and 132842 ± 0.54 for Dapoxetine Hydrochloride, respectively. The method was validated for precision, robustness and recovery. The limit of detection (LOD) and limit of quantitation (LOQ) was 0.010 μg/mL and 0.025 μg/mL for Tadalafil and 0.005 μg/mL and 0.020 μg/mL for Dapoxetine Hydrochloride, respectively. Statistical analysis showed that the method is repeatable and selective for the estimation of Tadalafil and Dapoxetine Hydrochloride.