Application

Sutitable for Colorimetric and UV Assays

Biochem/physiol Actions

Catalase is a ubiquitous antioxidant enzyme which catalyses the decomposition of hydrogen peroxide (H₂O₂) to water and oxygen. Hydrogen peroxide is formed in the eukaryotic cell as a by-product of various oxidases and superoxide dismutases. Hydrogen peroxide accumulation in cells causes oxidation of cellular targets such as DNA, proteins, and lipids leading to mutagenesis and cell death. Removal of the H₂O₂ from the cell by catalase provides protection against oxidative damage to living cells and its role in oxidative stress related diseases has been widely studied.

Features and Benefits

Useful for determining catalase activity - may be used in various tissues and cells Simple, optimized protocol - A simple colorimetric assay for analysis of peroxisome enrichment and catalase activity

General description

The Catalase Assay Kit contains all necessary components for studying catalase activity in various tissues and subcellular organelles.

Preparation Note

Use ultrapure water in preparation of all solutions.

Principle

This assay method is based on the measurement of the hydrogen peroxide substrate remaining after the action of catalase. First, the catalase converts hydrogen peroxide to water and oxygen (catalatic pathway) and then this enzymatic reaction is stopped with sodium azide. An aliquot of the reaction mix is then assayed for the amount of hydrogen peroxide remaining by a colorimetric method.10 The colorimetric method uses a substituted phenol (3,5-dichloro-2-hydroxybenzenesulfonic acid), which couples oxidatively to 4-aminoantipyrine in the presence of hydrogen peroxide and horseradish peroxidase (HRP) to give a red quinoneimine dye (N-(4-antipyryl)-3-chloro-5-sulfonatep-benzoquinone-monoimine) that absorbs at 520 nm

Suitability

Suitable for studying catalase activity in various tissues and subcellular organelles.

Unit Definition

One unit of catalase will decompose 1.0 micromole of hydrogen peroxide to oxygen and water per minute at pH 7.0 at 25 °C at a substrate concentration of 50 mM hydrogen peroxide.