Development of glucose oxidase biosensor using modified gold electrode by self-organized thiol monolayers: enzymatic reduction of nitro composites

• Grant number: 06/00763-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2006
• End date: December 31, 2006
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal Investigator: Silvia Helena Pires Serrano
• Grantee: Glaucia Freitas Menino
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Biosensors containing glucose oxidase will be development to work in anaerobic medium. The principal objective is to use the enzyme to produce free radicals in desaered solution containing glicose and nitrofurane derivative and, to compare the redox potential obtained via enzymatic reaction with that obtained using pure electrochemical pathway. The nitrofurane derivative is able to replace the molecular oxygen during the regeneration of the active enzyme form, after the glicose enzymatic cycle. The signal due the oxidation of the free nitro radical will be detected using cyclic or square wave voltammetry. Similar measurements will be done also using the biosensor in the absence of glucose, to quantify the percentage of the nitro radical, which is formed by the pure electrochemical pathway. The enzyme will be immobilized on a top gold electrode, which will be previously modified with thiol self assembling monolayer. The experimental activities are included inside of a thematic project from FAPESP (2001/01192-3), coordinated by Profa. Dra. Elizabeth Igne Ferreira, Faculdade de Ciências Farmacêuticas - USP and, Profa. Dra. Silvia Helena Pires Serrano, from Instituto de Química – USP, which is responsible for the electrochemical subproject.