Application of Azine Dyes for the Determination of Ranitidine Hydrochloride in Pharmaceutical Formulations

Abstract

Utilisation of azine dyes for the development of four simple spectrophotometric methods are described for the determination of Ranitidine hydrochloride (RTH) in pure form and pharmaceutical formulations. Method A is a direct one, which involves the formation of an ion-association complex (λmax:600 nm) between the drug molecule and wool fast blue BL. The other three methods, indirect ones, involve the addition of excess oxidant (chloramine-T, for method B; potassium permanganate, for method C, N-bromosuccinimide, for method D) of known concentration in acid medium to RTH and the determination of the unreacted oxidant by measurement of the decrease in absorbance of gallocyanine (GC for method B), cresyl fast violet acetate (CFVA for method C) or celestine blue (CB for method D) at a suitable maximum wavelength (λmax:540 nm for methods B&D and λmax: 555 nm for method C). The validities of the methods are tested against the spectrophotometric reference method and all are in good agreement.