Bioelectrochemical Study of the Deglycosylated Glucose Oxidase Enzyme for Application in Biofuel Cells.

• Grant number: 12/11968-3
• Support Opportunities: Scholarships in Brazil - Master
• Start date until: August 01, 2012
• End date until: November 30, 2013
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Frank Nelson Crespilho
• Grantee: Andressa Ribeiro Pereira
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

The enzyme glucose oxidase (GOx) is obtained through culture of Aspergillus niger is a flavoprotein approximately 160 kDa dimeric, and its molecular structure provides 16-25% (mass) of saccharides. The GOx catalyzes the reaction of oxidation of D-glucose to D-glucono-delta-1 ,5-lactone, whose cofactor flavin adenine dinucleotide (FAD) is reduced to FADH2 during the catalytic process. Each monomer of the structure of a cluster has GOx FAD spaced below 15 angstroms of the surface protein. Recent studies have reported that the Bioelectrochemistry FADH2 can be oxidized to -490 mV using a glassy carbon electrode and deglycosylated GOx (dGOx). This fact creates new possibilities of using as a biocatalyst in dGOx anodic reactions, especially for application in bio fuel cells (BC), since the removal of oligosaccharides decreases the distance between the electrode surface and FADH2, enabling the direct transfer of electrons . Thus, this master's project aims to study the kinetics of enzymatic dGOx microfibre fabric flexible carbon (FCF) for application in micro-BC. The enzyme dGOx be obtained by the deglycosylating GOx native and subsequently immobilized on the surface of the electrodes FCF by different methods of immobilization. Bioelectrocatalytic processes will be investigated using cyclic voltammetry and chronoamperometry. Finally, study will be the half-cell reactions for bioanodes, glimpsed on the implementation of dGOx bioanodes working on a prototype micro-BC.