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

A simple, fast, and precise reverse phase, High Performance Liquid Chromatography (HPLC) methodwas developed for the separation and quantification of Metformin HCI, Glimepiride and Pioglitazonein bulk drug and pharmaceutical dosage form using atorvastatin as internal standard. The quantification was carried out using CIS (250 x 4.6mm, 5μ) column and mobile phase comprising of methanol and phosphate buffer (pH 3) in proportion of75:25 (v/v). Flow rate was maintained at the rate of 1.0 ml/ min and the effluent 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 metfonnin, 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.