Validated Stability Indicating HPTLC, UHPLC and UV-Spectrophotometric Techniques for the Determination of Bepotastine Besilate in Presence of Its Oxidative Degradate

The study is aimed at developing methods which have a complete validation as stipulated in the ICH guidelines and to be applied for the determination of Bepotastine besilate (BB) in pure form and in pharmaceutical formulations in the presence of its oxidative degradation product. High performance thin layer chromatography (HPTLC), Ultra high performance liquid chromatography (UHPLC) and different spectrophotometric methods (first derivative, first derivative of ratio spectra and ratio difference are developed for simultaneous determination of bepotastine besilate in laboratory-prepared mixtures of bepotastine besilate with its oxidative degradate and in pharmaceutical formulations were used in the study design. Firstly, HPTLC was performed and separation occurred on silica gel 60 F254 plates, with butanol: ammonia (8:2, v/v) as a developing system. UHPLC in which separation occurred on a Kinetex C 18 column using methanol- 0.1% O-phosphoric acid - acetonitrile (70:20:10, by volume) as mobile phase, followed. And lastly was UV/Vis spectrophotometry which included first derivative determination of the drug at 252.6 nm, first derivative of ratio of peak amplitudes at 233.4, 250 and 275.6 nm and the ratio difference with the amplitude difference between (240 nm and 260 nm). Result showed that HPTLC method was applicable over the concentration range of 0.5-5 μg / band, while UHPLC method was linear over the concentration 2- 12 μg/mL and spectrophotometric methods were linear over the concentration range 20-120 μg/mL for bepotastine besilate. The proposed three techniques are quite accurate and precise. They can be used for routine analysis of bepotastine besilate in pharmaceutical formulation and stability indicating methods.