Determination and Validation of Metformin, Glimepiride, Pioglitazone Using Atorvastatin as an Internal Standardin Bulk Drug and Pharmaceutical Dosage Form

A simple, fast, and precise reverse phase, High Performance Liquid Chromatography (HPLC) method was developed for the separation and quantio cation of Metformin HCl, Glimepiride and Pioglitazone in bulk drug and pharmaceutical dosage form using atorvastatin as internal standard. The quantio cation was carried out using C 18 (250 × 4.6mm, 5�� ) column and mobile phase comprising of methanol and phosphate buffer (pH 3) in proportion of 75:25 (v/v). Flow rate was maintained at the rate of 1.0 ml/ min and the ef?uent was monitored at 230 nm. Percentage recoveries of the drugs from the tablet formulation were found to be 98.6%, 104.6% and 99.42% for metformin, pioglitazone and glimepiride respectively. Hence, the proposed method was found to be suitable for simultaneous determination of metformin, pioglitazone and glimepiride in pharmaceutical dosage form and bulk drug.