Mechanistic Aspects of Multistep Bioelectrocatalytic Oxidation of Fuels

Quantitative models were developed for dihydroxyacetone (DHA) production from glycerol oxidation coupled with electrocatalysis. A two-step kinetic model was developed to describe the reactions in bioelectrocatalysis involving electrochemical NADH regeneration. Planar and porous bioelectronic interfaces are modeled to simulate, predict and evaluate kinetics and diffusion in the bioconversion (Figure 1). Key parameters involve diffusivity of cofactor/substrate, electrocatalytic activity and enzyme kinetics. Model-based analysis indicates that the bioreactor is controlled by glycerol dehydrogenase kinetics for enzyme loadings lower than 1 mM and shifts to mass transport and incipient NADH oxidation kinetic control at higher enzyme loadings.