Voltammetric Measurement of Biomolecular Electron-Transfer Rates in Low Ionic Strength Solutions
Abstract
Numerical analysis of the sequential electron-transfer mechanism, A yields A+ + e-, A+ yields A2+ + e- demonstrates that the rate at which A can be directly oxidized to A2+ is inhibited in low ionic strength solutions by the coupled diffusion-migration of chemically-generated A+. The latter species, A+ is produced within the depletion layer by the homogenous reaction, A + A2+, and is electrostatically repelled from electrode surface, thereby reducing the flux of A at the electrode surface. Steady-state voltammetric currents corresponding to two examples of this reaction mechanism, the oxidation of tetrathiafulvalene (TTF) and the reduction of tetracyanoquinodimethane (TCNQ), have been measured at platinum microdisk electrodes over a wide range of electrolyte concentrations (0-0.1M).
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 16, 1990
- Accession Number
- ADA229918
Entities
People
- Bradford D Pendley
- Henry S. White
- Héctor D. Abruña
- John D. Norton
- Wendy E. Benson
Organizations
- University of Minnesota