Bioelectrodes Based on Electron Relay Modified Enzymes

Nature's redox enzymes function at different electrochemical potentials. To avoid uncontrolled electron-transfer between different enzymes, that would bring the enzymes to the same potential, nature surrounds the enzymes' redox centers with electrically-insulating protein shells. Because of these shells, redox enzymes cannot directly communicate with metal or semiconductor electrodes, i.e., they are not oxidized or reduced by direct electron- transfer to or from an electrode.