Determination of glimepiride in pharmaceutical formulations using HPLC and first-derivative spectrophotometric methods

Two validated analytical methods have been developed to determine glimepiride in pharmaceutical formulations using HPLC and 1st order derivative spectrophotometric techniques. Employing reverse phase HPLC method, the drug was analyzed by pumping a mixture of acetonitrile and 2% formic acid solution, pH 3.5 (80: 20 v/v) through a C(18) column (250 x 4.6 mm, 5 mu m) and detecting the eluents at 228 nm. The linearity range was found to be 20-140 mu g/mL with mean recovery of 100.52 +/- 0.33%. The second method was based on the formation of a complex of the drug with 2,3,5-triphenyl-2H-tetrazolium chloride in basic media. 1st order derivative spectrum made it possible to detect the complex at 413.5 nm. The linearity range was found to be 40-160 mu g/mL, with mean recovery of 100.33 +/- 0.47%. Both the proposed methods can reliably be used for routine analysis of glimepiride in raw material as well as in pharmaceutical formulations.