Abstract

STABILITY STUDIES ON NICLOSAMIDE USING DERIVATIVE SPECTROSCOPIC AND CHROMATOGRAPHIC METHODS

Shaza Wagiealla Shantier*, Elrashied Ali Elobaid, Elrasheed Ahmed Gadkariem

Abstract

First derivative spectrophotometric, high-performance liquid chromatographic (HPLC) and thin-layer chromatographic (TLC) methods were developed for the study of the effect of the pH, alkaline and temperature on the degradation of niclosamide. The drug was found to undergo alkaline hydrolysis with insignificant temperature variation effects. The degradation process was found to resemble the metabolic hydrolytic cleavage of niclosamide to chlorosalicylic acid (fluroscent compound) and 2-chloro-4-nitroaniline (yellow colored product). The pH-rate profile of the alkaline pH- dependent hydrolysis of niclosamide was studied within the pH range 5-7 which indicate a first order dependency of Kobs on [OH-]. In this study, a new stabilityindicating thin-layer chromatographic method was also developed for the separation of the drug and its degradation products in addition to the photochemical stability study that shows the photosensitivity of niclosamide.

Keywords: Niclosamide; Stability-indicating; Derivative spectroscopic; Chromatography.