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For the first time, we report a low-cost, disposable fully-papertronic screening platform for rapid screening and identification of electroactive microorganisms. This novel papertronic device is capable of simultaneous characterizing the electrogenicity of 10’s of the newly discovered, genetically engineered, bacteria. This work explored an exciting range of possibilities with the goal of fusing microbial fuel cell technology with ‘papertronics,’ the emerging field of paper-based electronics. Spatially distinct 64 sensing units of the array were constructed by patterning hydrophilic anodic reservoirs in paper with hydrophobic wax boundaries and utilizing 3-D multi-laminate paper structures. Full integration of a high-performance microbial sensor on paper can be achieved by improving the microbial electron exchange with the electrodes in an engineered conductive paper reservoir and reducing cathodic overpotential by using a solid electron acceptor on paper. Furthermore, the intrinsic capillary force of the paper and the increased capacity from the engineered reservoir allowed for rapid adsorption of the bacterial sample and promote immediate microbial cell attachment to the electrode, leading to instant power generation with even a small amount of the liquid.
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Biofabrication and characterization of multispecies electroactive biofilms in stratified paper-based scaffolds
Bioelectrochemical technologies have attracted significant scientific interest because the effective bacterial electron exchange with external electrodes can provide a sustainable solution that joins environmental remediation and energy recovery. Multispecies electroactive bacterial biofilms are catalysts that will drive the operation of bioelectrochemical devices. Unfortunately, there is a lack of understanding of key mechanisms determining their electron-generating capabilities and syntrophic relations within microbial communities in biofilms. This is because there are no universally standardized models for simple, rapid, reliable, and cost-effective fabrication and characterization of electroactive multispecies biofilms. The heterogeneous and long-term nature of biofilm formation has hampered the development of those models. This work develops novel biofabrication and analysis platforms by creating innovative, paper-based 3-D systems that accurately recapitulate the structure, function, and physiology of living multispecies biofilms. Multiple layers of paper containing bacterial cells were stacked to simulate different layered 3-D biofilm models with defined cellular compositions and microenvironments. Overall bacterial electrogenic capabilities through the biofilm structures were characterized by thoroughly monitoring collective electron flows through different external resistors. Changes in the type of species and order of stacking created biofilm modeling which allowed for the study of their electrogenic performance via variation in electron flow rate output. Furthermore, multi-laminate structures allowed for straightforward de-stacking and layer-by-layer separation for analyses of pH distribution and cellular viability. Our multi-laminate structures provide a new strategy for (i) controlling the biofilm geometry of 3-D bacterial cultures, (ii) monitoring the microbial electoral properties, and (iii) constructing an artificial biofilm layer by layer.
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- Award ID(s):
- 2100757
- PAR ID:
- 10405083
- Date Published:
- Journal Name:
- The Analyst
- Volume:
- 147
- Issue:
- 18
- ISSN:
- 0003-2654
- Page Range / eLocation ID:
- 4082 to 4091
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d2an01059c
