Simultaneous Estimation of Sitagliptin and Metformin in Pharmaceutical Formulation By HPTLC
A rapid, simple, specific and precise high-performance thin-layer chromatography (HPTLC) method was developed for the simultaneous estimation of sitagliptin (STG) and metformin (MET) content in a fixed dose pharmaceutical formulation and also in bulk drug. In the developed method, aluminium backed silica gel 60 F254 HPTLC plates were employed as stationary phase with BuOH, CHCl3, MeOH, (CH3CH2)2NH2 and HCOOH in a ratio of 4:0.5:2.5:1.5:0.06 (v/v) as a mobile phase, and chromatograms were scanned densitometrically at 206 nm. For STG and MET, Rf values were found to be 0.76 and 0.27, respectively. The linearity curve for the drugs was obtained in the concentration range of 2 - 7 μg per band and 20 - 70 μg per band, respectively. Correlation coefficients for STG and MET were 0.999 and 0.997, respectively. The developed method was confirmed by validating it as per the ICH guidelines. The limits of detection (LOD) and limits of quantification (LOQ) for STG and MET were found to be 0.014 & 0.042, and 0.013 & 0.040 μg per band, respectively. The developed method was found to be precise, accurate (mean recovery was within the range of 98 - 102%), specific and robust. Therefore, the method can be used for the simultaneous quality control analysis of the STG and MET in bulk drugs and pharmaceutical formulations.
Keywords: Simultaneous Estimation, Sitagliptin, Metformin, Fixed Dose Pharmaceutical Formulation, HPTLC