Author Description

The research presented in this thesis was composed of three parts. In the first part, the kinetics of the redox mediation between the azure dyes and the enzyme glucose oxidase was investigated. Electrochemical studies showed that azure dyes were fast mediators when dissolved in aqueous solutions. In the second part, the covalent immobilization of azure dyes in the biopolymeric matrix of chitosan was explored in order to design a reagentless glucose biosensor. These investigations indicated that the length of the tethering molecule was a crucial parameter, which controlled the mediation efficiency in the biosensor. The third part of this work was devoted to the preparation and characterization of a carbon paste-based electrochemical biosensor for glucose. The paste was modified with an azure eosinate mediator and glucose oxidase, and its analytical performance was tested under the conditions of diffusional and convective mass transport.