A Robust and Validated UV–Visible Spectrophotometric Method for Quantitative In Vitro Dissolution Evaluation of Azilsartan Medoxomil in Multiple Media Systems

A robust and validated UV–Visible spectrophotometric method was developed for the quantitative in vitro dissolution evaluation of azilsartan medoxomil tablets across multiple physiologically relevant media. Dissolution studies were performed using USP Apparatus II (paddle method) at ۵۰ rpm in ۹۰۰ mL of dissolution media maintained at ۳۷ ± ۰.۵ °C, including ۰.۱ N HCl (pH ~۱.۲), pH ۴.۵ acetate buffer, pH ۶.۸ phosphate buffers, and pH ۷.۸ water. Azilsartan medoxomil exhibited a λmax at ۲۴۶ nm in all buffered media and at ۲۵۴ nm in water. The method demonstrated excellent linearity over the concentration range of ۳۶–۵۴ µg/mL (r² = ۰.۹۹۶–۰.۹۹۹) for buffered media and ۱۸–۲۷ µg/mL for water and acetate buffer. Precision was within acceptable limits with %RSD < ۲.۰, and recovery ranged between ۹۵ and ۱۰۵% in selected media. Dissolution profiling revealed significant pH-dependent release, with >۸۰% drug release achieved within ۳۰ minutes in pH ۷.۸ phosphate buffer, compared to ~۴۶% in pH ۶.۸, ~۴۵% in water, ~۳۳% in ۰.۱ N HCl, and <۶% in pH ۴.۵ acetate buffer at ۶۰ minutes. No significant interference from excipients or media components was observed at the selected wavelengths. The method is suitable for routine dissolution analysis; however, additional studies are warranted to establish its broader regulatory applicability.

کلیدواژه ها:

Azilsartan medoxomil ، in vitro release ، UV &ndash ، Visible spectrophotometer method ، Validation ، quantitative ، Multiple Media Systems