Wiring gold nanoparticles and redox enzymes: a self-sufficient nanocatalyst for oxidation of carbohydrates directly with the molecular oxygen

Abstract

Development of artificial nanocatalysts, especially those incorporating highly active biocatalysts (enzymes) present in nature, is a rapidly developing field in nanocatalysis and nanomaterial science. Dehydrogenases are exceptionally attractive since they catalyze oxidation of various cheap/common substrates to more expensive and desired products. However, their usage in sustainable catalysis and/or incorporation in advanced nanomaterials with catalytic functions is limited due to immense problem which can be formulated as a question: how to get rid of electrons received from oxidized substrate? Here a solution to this problem is demonstrated. We have designed a unique nanomaterial composed of two redox enzymes (non specific glucose dehydrogenase and oxygen reducing laccase) and gold nanoparticle. Both enzymes have been wired via gold nanoparticles (10 nm) and direct electrochemical "communication" has been achieved, allowing electron transfer from the redox center of glucose dehydrogenase to a copper center of laccase. As a result, self-sufficient nanocatalysts have been synthesized and have been able to oxidize various carbohydrates directly with the molecular oxygen.