The present work describes development and validation of a simple, sensitive, precise, robust and stability-indicating high-performance liquid chromatographic method of analysis of flunarizine dihydrochloride, as a bulk drug. The separation was achieved by using a mobile phase of acetonitrile: monobasic ammonium phosphate buffer 0.1M pH 3.1 (55:45, v/v) and thermoscientific BDS-Hypersil column (250 mm X 4.6 mm, 5 μm) at flow rate of 1.0 ml/min. The detection was done at 253 nm. The retention time of flunarizine dihydrochloride was 6.48±0.5 min. This method has been successively applied to pharmaceutical dosage form. No chromatographic interference from the tablet excipient was found. Flunarizine dihydrochloride was subjected to stress conditions of hydrolysis, oxidation and thermal degradation. The degraded products were well resolved from the pure drug with significantly different retention time values. Linearity was found to be in the range of 25–100 μg/ml with significantly high value of correlation coefficient. The method was validated for precision, robustness and recovery. The limit of detection and quantization were 1.35 μg/ml and 4.11 μg/ml. The acid degraded product of flunarizine dihydrochloride was subjected to LCMS analysis. From the mass spectral data of degraded product, possible degradation pathway was outlined.
Loading....