DEVELOPMENT OF STABILITY INDICATING HIGH-PERFORMANCE THIN LAYER CHROMATOGRAPHIC METHOD FOR SIMULTANEOUS ESTIMATION OF TENELIGLIPTIN AND METFORMIN: APPLICATION TO ALKALINE DEGRADATION KINETIC STUDY

Stability indicating the HPTLC method was developed for simultaneous estimation of teneligliptin and metformin by using aluminum plates precoated with silica gel 60 F224 (Merck) and mobile phase toluene: methanol: GAA: TEA (5:4:0.5:0.5) with scanning wavelength of 257 nm. The developed method was validated for linearity, stability, accuracy, precision, robustness, LOD and LOQ as per ICH guidelines. The proposed method was successfully applied for the assay of metformin and teneligliptin in dosage forms and results were found to be in an acceptable range with a labeled claim of the pharmaceutical dosage form. Linearity for metformin and teneligliptin was observed\with correlation coefficient (r²) value of 0.999 and 0.993. The proposed method was also applied for degradation study of dosage form in alkaline acidic, Thermal, and photolytic conditions. Further, kinetic degradation study in alkaline conditions (0.1 N, 0.5 N, 1.0 N NaOH) at 60 °C and 80 °C are carried out. The degradation rate constant was also predicted at different temperatures and strengths of NaOH using kinetic methods. Degraded product of metformin and teneligliptin formed in the alkaline medium were isolated and characterized using Mass spectroscopy.