DEVELOPMENT AND VALIDATION OF A NOVEL STABILITY INDICATING RP-HPLC METHOD FOR QUANTITATIVE ESTIMATION OF TADALAFIL IN BULK AND TABLET DOSAGE FORM

A reliable and selective (RP-HPLC method was developed for the detection of tadalafil in tablet dosage forms. The study was conducted using a ZORBAX C18 non-endcapped column with a particle size of 5 µm and dimensions of 250 mm × 4.6 mm. Chromatographic separation under isocratic conditions was achieved using a mobile phase made up of methanol and acetate buffer in a 85:15 (v/v) ratio. The mobile phase was sonicated to remove gas before being run through a 0.45 µm membrane filter. The detecting wavelength was 284 nm, and the flow rate was maintained at 1 mL/min. In these conditions, the retention period of tadalafil was approximately 3.61 minutes.. The developed approach was validated in accordance with recognized standards by assessing elements such as linearity, accuracy, precision, and robustness. Linearity was seen in the concentration range of 0.5 to 200 µg/mL. With a mean recovery of about 99.2% and (RSD) values less than 2%, the method demonstrated good accuracy. Precision was confirmed in both intra- and inter-day studies, and strong reproducibility was demonstrated by RSD values that were consistently less than 2%. Robustness testing confirmed the method's reliability with deliberate, small changes in analytical conditions. Additionally, studies on forced deterioration were conducted in a variety of stress environments, including neutral, acidic, alkaline, photolytic, and oxidative ones. Under these circumstances, tadalafil showed signs of degradation, and the resulting degradation products were identified and monitored using the standard methodology. All things considered, this straightforward and effective method can be used to regularly test tadalafil in pharmaceutical formulations. Additionally, by providing useful details about the drug's stability profile, the degradation test results improve its use in quality control and stability testing prog.