Development and validation of a stability-indicating RP–HPLC method for estimation of atazanavir sulfate in bulk

A stability-indicating reverse phase–high performance liquid chromatography (RP–HPLC) method was developed and validated for the determination of atazanavir sulfate in tablet dosage forms using C(18) column Phenomenix (250 mm×4.6 mm, 5 μm) with a mobile phase consisting of 900 mL of HPLC grade methanol and 100 mL of water of HPLC grade. The pH was adjusted to 3.55 with acetic acid. The mobile phase was sonicated for 10 min and filtered through a 0.45 μm membrane filter at a flow rate of 0.5 mL/min. The detection was carried out at 249 nm and retention time of atazanavir sulfate was found to be 8.323 min. Linearity was observed from 10 to 90 μg/mL (coefficient of determination R(2) was 0.999) with equation, y=23.427x+37.732. Atazanavir sulfate was subjected to stress conditions including acidic, alkaline, oxidation, photolysis and thermal degradation, and the results showed that it was more sensitive towards acidic degradation. The method was validated as per ICH guidelines.