Stability Indicating TLC Method for Quantification of Brexpiprazole in Bulk and Its Pharmaceutical Dosage Form and Determination of Content Uniformity.

A sensitive, selective and precise high performance thin layer chromatographic method has been developed and validated for the quantification of Brexpiprazole in bulk drug and in pharmaceutical dosage form. The method employed HPTLC aluminum plates (pre-coated with silica gel 60 F254) as stationary phase while n-butanol was used as mobile phase. The Rf value of Brexpiprazole was observed to be 0.38. The densitometric analysis was carried out in absorbance mode at 215 nm. The linear regression analysis data for the calibration plots showed a good linear relationship for Brexpiprazole over a concentration range of 200-1,600 ng band-1. The limit of detection and limit of quantification for Brexpiprazole was found to be 66 and 200 ng band-1. To find out the possible degradation pathway, forced degradation studies were performed. The stock solutions of Brexpiprazole (1,000 μg mL-1) were subjected to acid and alkali hydrolysis, chemical oxidation, dry heat degradation and photo degradation. The drug was found to be susceptible to acid and alkali hydrolysis, chemical oxidation, photo degradation and dry heat. The degraded product peaks were well resolved from the pure drug peak with significant difference in their Rf values. Stressed samples were analyzed using developed HPTLC method. The proposed method was validated with respect to linearity, accuracy, precision and robustness. The method was successfully applied to the estimation of Brexpiprazole in marketed formulation and determination of content uniformity of tablet formulation. Statistical analysis showed that the method is repeatable, selective, and precise.