Simultaneous Spectrophotometric Estimation of Pioglitazone, Metformin HCl and Glimepiride in Bulk and Formulation

Abstract

Three sample, accurate and economical spectrophotometric methods i.e., simultaneous equation method, derivative spectroscopy method and area under the curve method have been developed for the simultaneous estimation of pioglitazone, metformin HCl and glimepiride in their combined dosage formulation. Pioglitazone shows absorbance maxima at 267 nm, metformin HCl at 238 nm and glimepiride at 226 nm in methanol. The methods allow rapid analysis of triple drug combination with high degree precision and accuracy. All three drugs exhibit linearity with absorbances in the concentration ranges employed for the methods. Results of the methods were validated statistically and by recovery studies.