Determination and Evaluation of Doses of Metronidazole in Different Quantities and Formulations with Multiple Spectroscopic Methods

Abstract

Three quick and sensitive spectrum methods have been suggested to determine Metronidazole. All spectral methods that were used included reducing Metronidazole by mixing zinc powder with hydrochloric acid. The first method (A) included the process of the conjugation of resorcinol reagent with metronidazole and the production of red chromophores, which was then estimated spectrally at a maximum wavelength of 520 nm. Method–B including the reaction p-chloro benzaldihyde in acidic medium to product yellow color Schiff base has an absorbance at 305 nm. The method C employing a charge transfer reaction with hydroquinone accepter in basic medium to product orange to yellow product absorbed at 335 nm. The best experimental conditions were used by applying the beer's Law for a range of concentrations 2.0-50 μg ml-1, 1.0-35 μg ml-1 and 1.5-30 μg ml-1for methods A, B and C respectively, and the corresponding molar absorptivity values are 1.375×104, 8.672×104, 1.995×104 L mol-1cm-1 with a Correlation coefficient of 0.9996, 0.9998, and 0.9988 and Limits Of Detection (LOD) 0.145 μg ml-1, 0.0776 μg ml-1and 0.110 μg ml-1 and Limits of Quantitation (LOQ) 0.4412 μg ml-1, 0.2352 μg ml-1and 0.3333 μg ml-1 for methods A, B and C Sequentially. The methods were successfully applied to the determination of Metronidazole in pharmaceutical preparation.