Mediated enzyme electrodes for biological fuel cell and biosensor applications

Integration of enzymes, redox mediators and high surface area materials to provide bioelectrochemical platforms capable of efficiently transferring electrons between chemicals and electrodes is a dynamic and rapidly expanding research area. These bioelectrochemical reactions are enabled by designing efficient mediated electron transfer processes between selected enzymes and electrode materials. Targeted synthesis of a library of osmium based redox mediator complexes possessing a range of redox potentials is presented whereby these mediators are designed to possess the dual function of mediation and covalent immobilization. In addition to designing inbuilt immobilization strategies for mediators, anchoring a support to surfaces can improve the stability of an enzyme/mediator layer compared to physisorbed films. An overview of some of the strategies we have adopted towards the fabrication of these anchored redox active biocatalytic films on supported pre-functionalized electrodes is presented.