Impurity profile study of pioglitazone and glimepiride combination drug product by liquid chromatography

A reverse phase highperformance liquid chromatographic (RP-HPLC) method in gradient mode has been developed and evaluated for its ability to simultaneously establish the level of known impurities as well as the unknown impurities in pioglitazone and glimepiride tablets. The best separation was achieved on Eclipse XDB-C8, 5m, 4.6  150mm column. Use of 0.1N sodium dihydrogen phosphate dihydrate buffer pH 3.0, acetonitrile and methanol, as mobile phase at flow rate of 1.2 mL min enabled acceptable resolution of pioglitazone and glimepiride from possible impurities.UV detection was performed at 230nm. The developed method was validated in term of selectivity, linearity, accuracy using spiked levels of impurities, precision (repeatability and reproducibility), limit of detection, limit of quantification and ruggedness. Overall, the proposed method was found to be highly sensitive, suitable and accurate for quantitative determination of known and unknown impurities in dosage form without any interference from the excipients.  2009 Trade Science Inc. INDIA Trade Science Inc.