Novel UV Spectrophotometric approaches for the concurrent determination of Teneligliptin and Metformin in Tablet Formulation

In the study simultaneous assessment of teneligliptin hydrobromide hydrate and metformin hydrochloride in tablets were developed and validated by four new UV spectroscopic approaches. The ratio difference approach was used to measure the variation in two selected amplitudes of ratio spectra, and the regression equation was employed to determine the amounts of pharmaceuticals. The second approach, known as the first derivative of ratio spectra approach, the UV spectra were transformed into their ratio spectra and corresponding first derivatives, and the first-derivative signal was gauged at 275 and 226.2 nm for metformin hydrochloride and teneligliptin hydrobromide hydrate, sequentially, making use of 2 nm as the wavelength interval (Δλ) and a factor of 1 as a scaling factor, respectively. Whereas absorbance subtraction method works with the principle of finding isosbestic point and calculating absorption factor. The fourth approach, known as the dual wavelength method, relies on computing the absorbance difference at two different wavelengths where the other drug has same absorbance. Linearity and range, specificity, accuracy, precision, limit of detection and quantification were among the criteria evaluated during validation of the new methods in agreement with ICH recommendations and found to be within the permitted limits. For both the medicines, a linear response was observed in all four methods over the concentration sequence of 2-12 µg/ml. Therefore, the proposed methodologies may be successfully used for the concurrent evaluation of teneligliptin hydrobromide hydrate and metformin hydrochloride in tablet form.