Carbon Fiber Anode of Biofuel Cell with Immobilized Bacteria and Membrane Fractions

Abstract

Four types of carbon fiber materials (CFMs) obtained by electrospinning polyacrylonitrile solutions are considered. The CFMs intertwine with cells of Gluconobacter oxydans or with their membrane fractions (MFs). Bioelectrochemical characteristics of the electrodes (chrono- and voltamperometric, as well as impedance spectra) are studied. Electrodes are considered a model of the anode of the microbial biofuel cell (MFC). Ethyl alcohol is the oxidized substrate. MALDI-TOF MS demonstrates that MFs retain the protein structure of whole cells and therefore can be used as analogues of whole cells. It is shown that the MFC based on carbon fiber material obtained after 30-min treatment at 1000°C has the highest power and stability. When MFs are used as a biocatalyst, nonmediated charge transfer is observed for all studied CFMs. These results can be successfully used for the design of biosensors and MFCs.