A rotating disk electrode for kinetic studies of superoxide dismutases: Applicability in a wide pH range and for continuous monitoring of enzyme inactivation

doi:10.1016/0003-2697(83)90432-3

Analytical Biochemistry

Volume 132, Issue 1, 1 July 1983, Pages 110-114

https://doi.org/10.1016/0003-2697(83)90432-3 Get rights and content

Abstract

A rotating disk electrode coated with a thin mercury film is described. It is suitable for electrochemical determinations of the catalytic constant of superoxide dismutase in a much wider pH range than that accessible to polarographic methods. In particular this is the only direct method, except for pulse radiolysis, that allows mechanistic studies of the enzyme in the physiological pH range. Furthermore, the continuous response of this electrode allows enzyme activity changes characterized by half-lives in the range from a few to 10³ s. to be followed.

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A rotating disk electrode for kinetic studies of superoxide dismutases: Applicability in a wide pH range and for continuous monitoring of enzyme inactivation

Abstract

Biochim. Biophys. Acta

Anal. Biochem

Arch. Biochem. Biophys

J. Biol. Chem

Advan. Enzymol

J. Phys. Chem