The search for alternative forms of energy is now widespread, and is slowly coming to the world of enzymes. Redox active enzymes can catalyze the oxidation of organic substrates such as methanol and ethanol very rapidly. They are an attractive alternative to precious metal catalysts for several reasons. Thus, enzymes holds great promise as a means of producing clean electrical energy from readily available fuels. The slow transfer of electrons from enzymes into electrodes is the major technical hurdle that remains. Modified electrodes are required to make this transfer rapid.
One strategy is to modify electrode surfaces with enzymes. The modified electrodes vary in their design, but all have the same purpose of transferring electrons into an electrode via a conductive mediator. The mediator varies from inorganic materials to the organic molecule pyrroloquinoline quinone. For example, a redox cofactor can be tethered to the electrode surface in a manner that promotes electron transfer from the enzyme active site to the cofactor then to the electrode. Electrically active organic molecules have also been attached to enzyme surface residues.
Our goal is to find conditions that will best allow an enzyme to transfer electrons from substrate into an electrode, providing an efficient anode for a biofuel cell.
Click here for an excellent website on bio-fuel cells.
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