Abstract
Considering alternative energy supply sources, miniaturized bioelectronic devices as biofuel cells can be attractive bioelectrocatalytic systems. Biological fuel cells utilize microorganisms or enzymes as biocatalysts to convert biochemical energy into electricity. In order to elaborate miniature and implantable biofuel cells, a compartment-separating membrane is excluded. Immobilization of enzymes and mediators on the conducting support are thus required. A variety of immobilization methods on different supports have been used for enzyme applications in biotechnology and environment. However, incorporation of enzymes in electropolymerized films such as polypyrrole impregnated with electron-transfer mediators has never been carried out in biofuel cell design. This technique largely developed for a variety of biomolecules provides very convenient and stable biocatalyst interfaces investigated for biosensor development. The biomolecule immobilization on electrode surfaces can be carried out either by entrapment or by covalent binding to electrochemically polymerized films. he aim of this work was to elaborate operational membrane contactors based on enzymes entrapment within electrochemically polymerized polypyrrole films to develop a glucose/O2 biofuel cell. Carbon porous tubes were used as original conducting membrane support for enzyme incorporation and for transport of dissolved dioxygen solution via convective flow, through the porosity. Such biofuel cell was based on laccase and glucose oxidase enzymes. Laccase reduced dissolved dioxygen in presence of mediator such as 2,2' -azinobis (3-ethylbenzothiazoline-6-sulfonate) diammonium salt (ABTS 2–) at the cathode of the biofuel cell, whereas Glucose Oxidase oxidised glucose in presence of 8-hydroxyquinoline-5-sulfonic acid hydrate (HQS) at the anode. Carbon porous tubes were used as original conducting membrane support for enzyme incorporation and for transport of dissolved dioxygen solution via convective flow, through the porosity.