Development and validation of stability indicating reverse phase HPLC method for the determination of impurities in pioglitazone hydrochloride

The present paper describes a reverse phase HPLC method for the quantitation of pioglitazone hydrochloride in the presence of its impurities. The active pharmaceutical ingredient (API) of pioglitazone hydrochloride was subjected to stress conditions viz., hydrolysis, oxidation, photolysis and thermal degradation. The drug was found to be sensitive under basic and oxidation environment. Successful separation of the drug from the degradation products were achieved on Gemini C18 (250 x 4.6 mm, 5μm) column using the mobile phase consisting of 50:50 v/v acetonitrile:0.05M potassium dihydrogen orthophosphate buffer of pH 3.0 (adjusted using 10%v/v ortho phosphoric acid in water) and at a flow rate of 1.0 mL/min. Column oven temperature was kept at 40°C and quantitation was achieved with UV detection at 225 nm. The method was validated in terms of accuracy, precision, linearity, limits of detection, limits of quantitation and robustness. As the proposed method could effectively separate the drug from its impurities, it can be employed as stability-indicating method for the determination of instability of this drug in API samples of pioglitazone hydrochloride.