The reaction between ferrocytochrome c and hydrogen peroxide
type: CreativeWork
description: The reaction between ferrocytochrome c and hydrogen peroxide has been studied to determine possible reaction mechanisms. This was done by investigating the effect of various physical factors, such as hydrogen ion concentration, ionic strength and temperature, on the reaction and by studying the kinetics of the reaction. The study of pH and ionic strength showed that an ionization occurred at pH 7.8 which influenced the reactivity of the cytochrome c. The reaction was studied kinetically at pH 8.1 and pH 6.6. At pH 8.1 simple kinetics showed an uncomplicated reaction between ferrocytochrome c and hydrogen peroxide. The kinetic studies at pH 6.6 showed that ferrocytochrome c, hydrogen peroxide and ferricytochrome c (acting as a product catalyst) were involved in the reaction. The product catalysis complicated the kinetics and difficulty was experienced in fitting a suitable reaction mechanism. Copper ions have been found to catalyse reactions similar to that studied here. The effect of a copper histidine complex was therefore investigated on the reaction at pH 8.7. The copper complex was found to catalyse the oxidation of ferrocytochrome c by hydrogen peroxide and the kinetic studies of this oxidation showed that the reaction could be fitted to a simple mechanism which did not involve the formation of intermediate complexes. An unusual feature of the reaction was the ability of the cytochrome c, after complete oxidation, to undergo reduction, which is dependent on the presence of both hydrogen peroxide and copper ions.
abstract: The reaction between ferrocytochrome c and hydrogen peroxide has been studied to determine possible reaction mechanisms. This was done by investigating the effect of various physical factors, such as hydrogen ion concentration, ionic strength and temperature, on the reaction and by studying the kinetics of the reaction. The study of pH and ionic strength showed that an ionization occurred at pH 7.8 which influenced the reactivity of the cytochrome c. The reaction was studied kinetically at pH 8.1 and pH 6.6. At pH 8.1 simple kinetics showed an uncomplicated reaction between ferrocytochrome c and hydrogen peroxide. The kinetic studies at pH 6.6 showed that ferrocytochrome c, hydrogen peroxide and ferricytochrome c (acting as a product catalyst) were involved in the reaction. The product catalysis complicated the kinetics and difficulty was experienced in fitting a suitable reaction mechanism. Copper ions have been found to catalyse reactions similar to that studied here. The effect of a copper histidine complex was therefore investigated on the reaction at pH 8.7. The copper complex was found to catalyse the oxidation of ferrocytochrome c by hydrogen peroxide and the kinetic studies of this oxidation showed that the reaction could be fitted to a simple mechanism which did not involve the formation of intermediate complexes. An unusual feature of the reaction was the ability of the cytochrome c, after complete oxidation, to undergo reduction, which is dependent on the presence of both hydrogen peroxide and copper ions.
author: Hulett, Leslie Graham
language: eng
date published: 1968
date modified: 2026-07-22T22:23:29Z
provider: University of Cape Town
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Department of Geological Sciences

PropertyValue
property ID: Handle
value: http://hdl.handle.net/11427/22300