SGER: Nanoporous Conductive Sol-Gel Biocatalysis for Novel Cofactor Regeneration

Arizona State University, Scottsdale AZ

Investigators

Abstract

Abstract Proposal Title: SGER: Nanporous Conductive Sol-Gel Biocatalysis for Novel Cofactor Regeneration Proposal Number: CTS-0538633 Principal Investigator: Chan Beum Park Institution: Arizona State University Analysis (rationale for decision): This proposal will address the critical use of cofactors for oxidoreductases, such as the expensive pyridine cofactor, which must be economically regenerated for a variety of technological applications. Although electrochemical recycling of cofactors has been regarded as a potentially useful approach, there is a clear obstacle in that only enzymes in the immediate vicinity of electrode surface are effectively involved. This exploratory research project will examine a highly innovative approach that uses an "electronically-conductive" sol-gel bioreactor for cofactor regeneration. By entrapping oxidoreductases in a conductive sol-gel hybrid matrix and by manipulating the chemical properties of the nanoporous gel, it is hypothesized that the cofactor will be efficiently recycled throughout the entire reactor system. This approach by the principle investigator shows acute insight into the key challenges in the regeneration process, but the project is clearly high risk because of the necessity of preparing a precise "composite" of conductive sol moiety/polypyrrole/graphite/metal particles for the sol-gel synthesis which would be based on silica-based sol precursors, such as trialkoxysilanes. The chemical composition of the gel precursors must be carefully correlated with knowledge of the in situ cofactor regeneration efficiency and the desired product yield. Successful demonstration of this approach, however, would likely revolutionize the applicability of electrochemical regeneration for biocatalysts. The difficulty and expense of cofactor regeneration for oxidoreductases is a key roadblock for the wider syntheses of important valued-added products including pharmaceuticals, food additives, perfumes, insecticides, and pesticides. This approach would open an entirely new avenue of scientific investigation and would lead to new areas for fundamental research and engineering. Broader technological applications in the areas of biosensors and biofuel cells are also possible. Results from the research will be incorporated into upper-level chemical engineering coursework, which will be a significant contribution to the enhancement of the engineering curriculum.