Absorption Spectrophotometric Method Development for The Simultaneous Estimation of Anti-Diabetic Drugs Sitagliptin and Glimepiride

The aim of the present research was to develop an absorption spectrophotometric analytical method utilizing economical 0.1 N NaOH solvent for the concurrent estimation of Sitagliptin (SGT) and Glimepiride (GMP). Wavelengths 228nm and 267.5nm were selected for absorbance measurement of GMP and SGT respectively. From the nature of UV spectra simultaneous equation and absorption correction method was found suitable for determination of both drugs. For selection of critical parameters, effect of input variables on spectrum characteristics were studied and developed method was validated as per ICH Q 2 R1 regulatory guidelines. Linearity of the drugs was ascertained over the conc range 20 to 250μg/ml and 1 to 24μg/ml for SGT and GMP respectively. The accuracy was studied and standard deviation 0.0318-3.0515 for SGT and 0.4287-3.4801 for GMP found within acceptable limit; and the assay study data was found 99.54 % for SGT and 95.61 % for GMP. The stability of the method was studied by minor variation in the wavelength, scan speed. The developed method is rigid, robust and efficient for the estimation of SGT and GMP from their respective/combined dosage form. The effort was made to develop sustainable economic analytical method utilising common solvent for drug sitagliptin and water insoluble glimepiride.