STUDIES ON HPTLC AND RP-HPLC METHODS FOR DETERMINATION OF TADALAFIL IN PHARMACEUTICAL DOSAGE FORM

Tadalafil is a selective phosphodiesterase Type 5 enzyme inhibitor. Simple and sensitive High Performance Thin - Layer Chromatography (HPTLC) and Reversed - Phase High - Performance Liquid Chromatography (RP-HPLC) methods have been developed for estimation of tadalafil in pharmaceutical dosage form. Separation of tadalafil was achieved on HPTLC aluminum sheets of silica gel 60 F254 with mixture of toluene: methanol (7.2: 2.8 V/V) as the mobile phase. tadalafil obeyed linearity in the concentration range of 300 - 800 ng/band with correlation coefficient (r2) 0.9994. Detection was performed densitometricaly at 284 nm with Rf 0.50 ± 0.02. RP-HPLC separation was achieved using Qualisil C18 column on mixture of methanol: water (75: 25 % V/V) as the mobile phase. Linearity was plotted in range of 2 – 12 μg/mL and (r2) value as 0.9998. The retention time was found to be 4.82 ± 0.02 min. The developed HPTLC and RP-HPLC methods have been successfully applied for the determination of tadalafil in bulk and pharmaceutical formulation. Both these methods were statistically compared.