Enzymatic Determination of Small Quantities of Hydrogen Peroxide ∗

Abstract

Summary

Two reactions, (a) H₂O₂ with ethanol in the presence of an excess of catalase, and (b) acetaldehyde with NADH in the presence of yeast alcohol dehydrogenase have been employed in assays of H₂O₂ during the oxidation of a suitable substrate with an H₂O₂ generating enzyme. A method is described for the accurate measurement of minute amounts of H₂O₂. L-α-hydroxy acid oxidase from rat liver, L-amino acid oxidase from rat kidney, and uric acid oxidase from Candida utilis were used as H₂O₂ generating enzymes. The amount of H₂O₂ produced was determined photometrically from the change in optical density at 340 mμ. Recoveries with this method exceeded 80%.