(439b) Nano Carbon Materials for Efficient Cofactor Regeneration – Toward Solar Driven Biosynthesis

One unique feature of nanostructured carbon materials for electrochemical applications is that they can substantially reduce overpotentials of electrobiochemical reactions.  Cofactors such as NADH have been shown greatly valuable in developing cell-free multistep biosynthetic reaction pathways, including the direct enzymatic reduction of carbon dioxide to value-added chemicals.  While such reactions are greatly appealing, regeneration of cofactors using either chemical or electrochemical means can be expensive, often presents a major hurdle in large scale applications.   Solar driven cofactor regeneration may afford a new avenue for energy-efficient biosynthesis.   Toward that, we have demonstrated that regeneration of NADH from NAD⁺ can be achieved at a potential ~0.5 V, very close to the theoretical redox potential (0.33V) of NADH, and much lower than those realized with regular carbon electrodes (~1.0 V).   Similar to biological energetic pathways where cofactors serve as the major energy storage agents, this work also promises new strategies in harvesting solar energy for both biosynthesis and other bioelectrochemical applications.