Development and validation of stability indicating HPTLC method for pioglitazone hydrochloride and metformin hydrochloride

Stability indicating HPTLC method was developed and validated for Pioglitazone hydrochloride (PIO) and Metformin Hydrochloride (MET). The chromatographic separation were carried out using silica gel precoated aluminium plate 60F254, (20×10 cm2 and 10×10 cm2) as stationary phase and butanol: 1, 4-dioxane: glacial acetic acid in the proportion of 5: 3: 2 v/v/v as mobile phase for Pioglitazone hydrochloride and Metformin hydrochloride. The wavelength selected for detection was 226 nm. This method was used for determination of Metformin hydrochloride and Pioglitazone hydrochloride from pure powder mixture and tablet dosage form. Stability indicating HPTLC method was performed by keeping sample solution in different stress condition. The stability study was performed for acid degradation, photolytic degradation and thermal degradation. In proposed developed method, Rf value of Metformin hydrochloride and Pioglitazone hydrochloride was found to be 0.17±0.02 and 0.72±0.01 respectively. The method has been validated for linearity, accuracy, precision, robustness, limit of detection and limit of quantification. Linearity of Metformin hydrochloride and Pioglitazone hydrochloride were found in the range of 2000-18000 ng/band and 60–540 ng/band respectively. The percentage recoveries obtained for Metformin hydrochloride and Pioglitazone hydrochloride were found to be in range of 98.62% to 100.62%. LOD and LOQ were found to be 5.65 ng/band and 17.64ng/band for Metformin hydrochloride and 0.259 ng/band and 0.786 ng/band for Pioglitazone hydrochloride, respectively.