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PEDOT:PSS-based Multilayer Bacterial-Composite Films for Bioelectronics
Tom J Zajdel1,2, Moshe Baruch2, Gábor Méhes2,3
1Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, California, United States of America.
Scientific Reports
|October 18, 2018
Summary
Researchers developed a novel multilayer conductive bacterial-composite film (MCBF) to overcome biofilm thickness limitations. This advancement significantly boosts current output for microbial electrochemical systems, enabling better bioelectronics and biosensing applications.
Area of Science:
- Microbial electrochemistry
- Bioelectronics
- Biosensing
Background:
- Microbial electrochemical systems (MES) offer eco-friendly energy conversion for wastewater treatment and bioelectronics.
- Limited biofilm thickness hinders signal-to-noise ratios in biosensors and bioelectronics, requiring larger devices.
- Developing thicker, functional biofilms is crucial for miniaturization and deployment of bioelectronic devices.
Purpose of the Study:
- To create a thicker biofilm structure for enhanced signal generation in biosensors.
- To embed electroactive bacteria within a conductive matrix for improved electron transfer.
- To develop a versatile method for creating multilayer conductive bacterial-composite films (MCBFs).
Main Methods:
- Embedding electroactive bacteria (Shewanella oneidensis MR-1) within a conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) matrix.
- Utilizing a flow-through method for bacterial encapsulation, achieving over 90% viability.
- Electropolymerizing the composite film on a carbon felt substrate to form multilayer conductive bacterial-composite films (MCBFs) up to 80 µm thick.
Main Results:
- MCBFs exhibited a tightly interleaved structure of bacteria and conductive PEDOT:PSS.
- Shewanella oneidensis within MCBFs demonstrated efficient direct and riboflavin-mediated electron transfer.
- MCBFs generated 20 times more steady-state current compared to native biofilms in bioelectrochemical reactors.
Conclusions:
- The developed MCBF approach effectively increases biofilm thickness and current output.
- This method allows for controlled fabrication of bacterial composite films for enhanced performance in MES.
- The technology has direct applications in environmental sensing and miniaturized organic electronics.
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