Using of Oxidative - Coupling Reaction in Spectrophotometric Determination of Metoclopramide Hydrochloride in Pharmaceutical Preparations

Abstract

A simple, sensitive, and rapid spectrophotometric method has been developed for the determination of metoclopramide hydrochloride (METH). The method includes the oxidative coupling reaction of metoclopramide with 2,5-dihydroxybenzoic acid using potassium periodate as an oxidizing agent in an aqueous medium and at pH of 4.5 to give a water-soluble colored product. The highest absorbance occurs at a wavelength of 500 nm. The linear range of Beer's law was within the concentration range of 5-75 µg/ml of (METH) and the value of the molar absorptivity  2.196 x10³ l.mol^-1.cm^-1 and Sandell's index value was equal to 0.0449 µg/ cm². The relative standard deviation value was ≤ 2.98, while the LOD and LOQ values were 0.059 µg.ml^-1 and 0.198 µg.ml^-1 respectively. The proposed method was successfully applied in the spectrophotometric estimation of metoclopramide preparations in the form of tablets and injections with acceptable recovery.