Determination of mebendazole and its formulations using 1H nuclear magnetic resonance spectrometry

Abstract

A sensitive and reproducible quantitative ¹H NMR assay for the determination of mebendazole and its formulations is described. The procedure is based on integrating the sharp singlet at 4.10 p.p.m. for the mebendazole methoxy protons relative to the clear quartet at 4.57 p.p.m. for the benzocaine methylene protons as internal standard. The ¹H NMR technique gave results in good agreement with those of the USP procedure and the difference in accuracy and precision between the two methods was not significant.