講演情報
[24a-1BN-9]Redox-Active Polymer Connecting Microbial Cells to an Extracellular Electrical Circuit
〇(D)Shenghan Gu1, Aoba UEKI2, Kuniaki NAGAMINE2, Saman AZHARI1, Gabor MEHES1, Takeo MIYAKE1,3 (1.WASEDA School of Information, Production and Systems, 2.Graduate School of Organic Materials Science, Yamagata University, 3.JST-PRESTO)
キーワード：
electroactive bacteria、redox polymer、extracellular electron transfer
Microbial electrochemical systems in which metabolic electrons from microbes are extracted to or injected from an extracellular electrical circuit have attracted considerable attention as environmentally-friendly energy conversion systems. Because most of the known microbes cannot exchange electrons with extracellular solids, electron mediators have been commonly used to connect cells to an electrode. Recently, we have shown that redox polymers (RPs) may be able to play the role of electrical wiring between non-electroactive bacteria (n-EAB) and electrodes, though a robust biofilm formation by electrode surface control is yet to be achieved.[1]
Herein, we demonstrate a RP conductive polymer coating on carbon felt (CF) to enhance current densities in microbial bioelectronic devices (Fig.1). RP is expected to not only improve the extracellular electron transfer (EET) of model organism S. oneidensis, but also the extraction of current from n-EAB (E. coli). Different from the existing approach of using genetic engineering to introduce EET into non-electroactive microorganisms [2] (such as expressing the Mtr pathway of S. oneidensis on the membrane of E. coli), our RP not only increases the effective surface area of the electrode but also enhances the density of the biofilm on the electrode surface during the EET process with n-EAB. In addition, we attempt to explain the EET mechanism of n-EAB in combination with our RP.
Our work is one of the first demonstrations of directly utilizing conjugated polymers to achieve EET process between n-EAB and external charge collectors, resulting in measurable current levels. The RP-modified electrode provides a new approach for engineering strategies to enhance the EET ability of microorganisms.
Herein, we demonstrate a RP conductive polymer coating on carbon felt (CF) to enhance current densities in microbial bioelectronic devices (Fig.1). RP is expected to not only improve the extracellular electron transfer (EET) of model organism S. oneidensis, but also the extraction of current from n-EAB (E. coli). Different from the existing approach of using genetic engineering to introduce EET into non-electroactive microorganisms [2] (such as expressing the Mtr pathway of S. oneidensis on the membrane of E. coli), our RP not only increases the effective surface area of the electrode but also enhances the density of the biofilm on the electrode surface during the EET process with n-EAB. In addition, we attempt to explain the EET mechanism of n-EAB in combination with our RP.
Our work is one of the first demonstrations of directly utilizing conjugated polymers to achieve EET process between n-EAB and external charge collectors, resulting in measurable current levels. The RP-modified electrode provides a new approach for engineering strategies to enhance the EET ability of microorganisms.