Stability indicating RP-HPLC method development and validation of metformin hydrochloride and glimepiride in bulk and pharmaceutical dosage form

A stability indicating RP-HPLC method was developed and validated for the determination of Metformin HCl and Glimepiride in tablet dosage form. The method was carried out using Agilent C18 column (250 mm×4.6 mm, 5 μ) with mobile phase consisting 25 mM Hexane-1-sulphonic acid buffer adjusted to pH 2.5 with ortho-phosphoric acid and acetonitrile (45:55 v/v), at a flow rate of 1.0 mL/min and the effluent monitored at 229 nm. The retention time of Metformin HCl and Glimepiride were found to be 3.55  0.5 and 5.82  0.5 min respectively. Linearity was observed over the concentration range of 150-750 μg/mL for Metformin HCl and 0.75-4.5 μg/mL for Glimepiride. The percentage recoveries of Metformin HCl and Glimepiride in the marketed dosage form found to be 101.6 and 99.9 respectively. The reliability and analytical performance of the proposed method were statistically validated for specificity, linearity, precision, accuracy, and ruggedness, detection, and quantification limits. The drug was subjected to stress conditions including acidic, alkaline, oxidation, photolysis and humidity degradation. The drug is more sensitive towards oxidation degradation. The method was validated as per ICH guidelines.