Stability indicating HPTLC method for determination of Metopimazine in pharmaceutical formulation and human plasma

Accurate, selective and sensitive stability indicating high performance thin layer chromatographic (HPTLC) method was developed and validated for determination of Metopimazine (MPZ) in presence of its degradation products; including the oxidative degradation product (Deg I) and the alkaline hydrolysis degradation product (Deg II; formerly reported as acid metabolite). The proposed method was applied for analysis of MPZ in pure form, pharmaceutical formulation (tablets) and human plasma over the concentration range of 0.4-1.4 μg band−1 with accuracy of mean percentage recovery 100.10 ± 0.941. The method depends on separation of MPZ from its degradation products on HPTLC silica gel 60 F254 plates using chloroform-methanol-ammonia (12:2:0.1, by volume) as developing system followed by densitometric measurement of bands at 254 nm. The method was validated according to ICH guidelines. The degradation products were well resolved from the pure drug with significantly different Rf values (MPZ, Rf = 0.58, Deg I, Rf = 0.35 and Deg II, Rf = 0.03). The results obtained by the proposed method were statistically compared to the reported HPTLC method, and there was no significant difference between them regarding both accuracy and precision; indicating the ability of the proposed method to be used for routine analysis of drug product.