A study of the electrochemical oxidation of hydrogen peroxide on a platinum rotating disk electrode in the presence of calcium ions using Michaelis-Menten kinetics and binding isotherm analysis

Emad A. Khudaish, Wafaa R. Al-Farsi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The present work demonstrates a potential suppression in the electrochemical signal of H2O2 oxidation due to the presence of Ca2+ ions. A mechanistic scheme was proposed to include a reversible interaction of Ca2+ ions with either the electrode surface binding sites (competitive) or the complex sites (non-competitive). The degree of inhibition was inspected by evaluating the kinetic currents as a function of [Ca2+] applying Koutecky-Levich kinetics. These observations were further supported with models based on enzyme kinetics such as Michaelis-Menten model applying Lineweaver-Burk plot along with non-linear least-square fitting analysis. The experimental results suggests that the strength of the complex binding sites decreases considerably with increasing [Ca2+] and that a single H2O2 molecule is required to combine with one available active binding site.

Original languageEnglish
Pages (from-to)4302-4308
Number of pages7
JournalElectrochimica Acta
Volume53
Issue number12
DOIs
Publication statusPublished - May 1 2008

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Keywords

  • Calcium ions
  • Hydrogen peroxide
  • Inhibition
  • Michaelis-Menten kinetics
  • Platinum electrode

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Analytical Chemistry
  • Electrochemistry

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