Applied Microbiology and Biotechnology

, Volume 96, Issue 3, pp 841–849

Prolongation of electrode lifetime in biofuel cells by periodic enzyme renewal

Authors

  • S. Rubenwolf
    • Laboratory for MEMS Applications, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
  • S. Sané
    • Laboratory for MEMS Applications, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
  • L. Hussein
    • Freiburg Materials Research Centre (FMF)University of Freiburg
    • Laboratory for Sensors, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
  • J. Kestel
    • Laboratory for MEMS Applications, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
    • ifm electronic GmbH
  • F. von Stetten
    • Laboratory for MEMS Applications, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
  • G. Urban
    • Freiburg Materials Research Centre (FMF)University of Freiburg
    • Laboratory for Sensors, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
  • M. Krueger
    • Freiburg Materials Research Centre (FMF)University of Freiburg
    • Laboratory for Sensors, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
  • R. Zengerle
    • Laboratory for MEMS Applications, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
    • BIOSS Centre for Biological Signalling StudiesUniversity of Freiburg
    • Laboratory for MEMS Applications, Department of Microsystems Engineering—IMTEKUniversity of Freiburg
Bioenergy and Biofuels

DOI: 10.1007/s00253-012-4374-8

Cite this article as:
Rubenwolf, S., Sané, S., Hussein, L. et al. Appl Microbiol Biotechnol (2012) 96: 841. doi:10.1007/s00253-012-4374-8

Abstract

Enzymatically catalyzed biofuel cells show unique specificity and promise high power densities, but suffer from a limited lifetime due to enzyme deactivation. In the present work, we demonstrate a novel concept to extend the lifetime of a laccase-catalyzed oxygen reduction cathode in which we decouple the electrode lifetime from the limited enzyme lifetime by a regular resupply of fresh enzymes. Thereto, the adsorption behavior of laccase from Trametes versicolor to buckypaper electrode material, as well as its time-dependent deactivation characteristics, has been investigated. Laccase shows a Langmuir-type adsorption to the carbon nanotube-based buckypaper electrodes, with a mean residence time of 2 days per molecule. In a citrate buffer of pH 5, laccase does not show any deactivation at room temperature for 2 days and exhibits a half-life of 9 days. In a long-term experiment, the laccase electrodes were operated at a constant galvanostatic load. The laccase-containing catholyte was periodically exchanged against a freshly prepared one every second day to provide sufficient active enzymes in the catholyte for the replacement of desorbed inactive enzymes. Compared to a corresponding control experiment without catholyte exchange, this procedure resulted in a 2.5 times longer cathode lifetime of 19 ± 9 days in which the electrode showed a potential above 0.744 V vs. normal hydrogen electrode at 110 μA cm−2. This clearly indicates the successful exchange of molecules by desorption and re-adsorption and is a first step toward the realization of a self-regenerating enzymatic biofuel cell in which enzyme-producing microorganisms are integrated into the electrode to continuously resupply fresh enzymes.

Keywords

Enzymatic biofuel cellLaccaseLifetimeLong-term stabilityAdsorptionBuckypaper

Copyright information

© Springer-Verlag 2012