Determination of catecholamines in pharmaceutical preparations by differential pulse polarography at the glassy carbon electrode

Abstract

A polarographic method has been developed for the assay of catecholamines in pharmaceutical preparations. The compounds were determined by direct anodic oxidation at the glassy carbon electrode using differential pulse polarography. Peak current was found to be linearly related to catecholamine concentration and the glassy carbon surface was not fouled by the products of the electrochemical oxidation. The effects of degradation products and of antioxidant on the polarographic method were investigated. The method was used to determine adrenaline and noradrenaline in solution formulations, and isoprenaline and methyldopa m tablets, and was found to give accurate and reproducible results. The polarographic method had the advantages of rapidity and simplicity, making it suitable for application in routine quality control of these preparations.