Electrochemical insight into the mechanism of electron transport in biofilms of Geobacter sulfurreducens

GERMÁN DAVID SCHROTT; PABLO SEBASTIÁN BONANNI; LUCIANA ROBUSCHI; ABRAHAM ESTEVE NUÑEZ; JUAN PABLO BUSALMEN

ELECTROCHIMICA ACTA

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2011 vol. 56 p. 10791 - 10795

0013-4686

Electroactive bacterial biofilms can be produced on a polarized electrode by forcing its use as the finalelectron acceptor for bacterial respiration. This strategy offers the researcher the unique possibility tocontrol the respiration process with extreme precision. The production of current, the accumulationof charge and the conducting properties of electroactive biofilms has been interrogated in this workthrough very basic electrochemical techniques including chronopotentiometry, chronoamperometry andcyclic voltammetry. Presented results indicate that charge can be accumulated in the biofilm conductivenetwork, that network conductivity does not represent a limit for current production and that both thesteady state current and the amount of accumulated charge depend on the redox state of cytochromeswiring the cells to the electrode. A model of biofilm conduction is presented as well.