ABSTRACT:
A simple, sensitive, rapid, accurate and precise spectrophotometric method was developed for simultaneous estimation of glimepiride and metformin in tablets by employing first order derivative zero crossing method and validated for accuracy, precision, ruggedness, linearity, range and specificity. The wavelengths selected for quantitation were 238.6 nm (zero cross point of metformin) for glimepiride and 230.0 nm (zero cross point of glimepiride) for metformin. Linearity was maintained within a concentration range from 4.0 - 30.0 µg/ml for glimepiride and 5 -30 µg/ml for metformin. The limit of detection limit and limit of quantification for glimepiride were found to be 2.0 and 4.0 µg/ml respectively and for metformin 5.0 and 8.0 µg/ml respectively. Accuracy was confirmed by recovery studies and precision by marketed formulation analysis. The mean % labeled claim ± S.D.for glimepiride and metformin were 99.12±0.187and101.22±0.812 respectively. % R.S.D. values for ruggedness studies were less than 2% indicated reproducibility of the method. Commercial tablet formulation was successfully analyzed using the developed method.