A New Colourimetric Assay for Monoamine Oxidase in Serum

Abstract

A new colourimetric assay for serum monoamine oxidase is described. This rapid and presise procedure employs 1-[(4-aminomethyl phenyl) azo]-2-naphthol as substrate. The enzymatically generated 1-[(4-formyl phenyl) azo]-2-naphthol is extracted into cyclohexane to form a coloured solution whose absorbanse is measured at500nm. The method proved to be extremely simple, and the results obtained corre ated well with those given by the standard method of McEwen.