Electron Transfer in Enzymatic Catalysis

Electron transfer between biocatalysts and electrodes is one of the key issues in bioelectrocatalytic systems and, thus, of profound importance for the overall performance of such electrode systems. This chapter will give an overview of the different approaches in connecting enzymes with electrodes and will also address the determination of kinetic parameters. This includes the heterogeneous electron transfer rate constant of redox molecules at electrode as well as the reaction rate constant of potential mediator molecules with enzymes. Special attention is given to direct electron transfer approaches; here, the application of conducting polymers and nanoparticles will also be discussed. Finally, the concepts of protein engineering in improving the heterogeneous electron transfer rate will be illustrated.