Stability-indicating HPLCâDAD methods for determination of two binary mixtures: Rabeprazole sodiumâmosapride citrate and rabeprazole sodiumâitopride hydrochloride

Two selective stability-indicating HPLC methods are described for determination of rabeprazole sodium (RZ)âmosapride citrate (MR) and RZâitopride hydrochloride (IO) mixtures in the presence of their ICH-stress formed degradation products. Separations were achieved on X-Bridge C18 column using two mobile phases: the first for RZâMR mixture consisted of acetonitrile: 0.025 M KH2PO4 solution: TEA (30:69:1 v/v; pH 7.0); the second for RZâIO mixture was at ratio of 25:74:1 (v/v; pH 9.25). The detection wavelength was 283 nm. The two methods were validated and validation acceptance criteria were met in all cases. Peak purity testing using contrast angle theory, relative absorbance and log A versus the wavelengths plots were presented. The % recoveries of the intact drugs were between 99.1% and 102.2% with RSD% values less than 1.6%. Application of the proposed HPLC methods indicated that the methods could be adopted to follow the stability of their formulations. Keywords: Rabeprazole sodium, Mosapride citrate, Itopride hydrochloride, Stability-indicating HPLCâDAD, Peak purit