Stability-Indicating HPTLC Method for Determination of Remogliflozin Etabonate and Vildagliptin in Tablets

A sensitive, selective, precise and stability-indicating high-performance thin-layer chromatographic (HPTLC) method is developed for the simultaneous estimation of remogliflozin etabonate and vildagliptin in the presence of their degradation products. The separation was performed in thin layer chromatography plate precoated with silica gel G60F254. The mobile phase consists of methanol:ethyl acetate:toluene:ammonia (1.5:4:4.5:0.1, v/v/v/v). Detection and quantification are performed with densitometer at 212 nm. The Rf values of remogliflozin etabonate and vildagliptin are 0.53 and 0.42, respectively. Degradation studies for the two drugs were carried out in acidic, alkaline, neutral, oxidative, photolytic and thermal stress conditions and analyzed. The suitability of this method for the quantitative determination of the compounds is proved by validation in accordance with the requirements laid down by International Conference on Harmonization (ICH). Linearity was found over the concentration range of 200-1000 ng/band with correlation coefficient of 0.9936 for remogliflozin etabonate and 100-500 ng/band with correlation coefficient of 0.9912 for vildagliptin. The method was successively applied to tablets containing two drugs and found to have no chromatographic interferences from the tablet excipients. The degradant formed was not interfering with estimation of two drugs makes the method more selective for the purpose intended.