Simultaneous determination of pioglitazone and glimepiride in their pharmaceutical formulations.

Four sensitive and precise spectrophotometric methods were developed and validated for the simultaneous determination of pioglitazone hydrochloride (PGZ) and glimepiride (GLM) in their pharmaceutical formulations. Among the methods adopted were direct absorbance, firstderivative (1D), second-derivative (2D) and first-derivative of ratio spectra (1DD). The selectivity of the proposed methods was checked using laboratory prepared mixtures. The proposed methods were successfully applied to the analysis of GLM and PGZ in their mixture and in pharmaceutical dosage forms without interference from other additives.