Microfabricated microbial fuel cell array for screening of electrochemically active microbes

Microbial fuel cells (MFCs) are devices that directly generate electricity from organic compounds. Development of efficient MFCs capable of producing high power requires not only optimization of MFC designs, but also exploring more electrochemically active microbes and finding optimum operating conditions. Devices capable of high throughput analysis can greatly accelerate these efforts. Here, we describe the development of an MFC array, a compact and user-friendly platform for direct characterization and comparison of electrochemically active microbes in parallel. The MFC array consists of 24 independent miniature MFCs on a single 5 × 7.5 cm chip format, capable of 24 parallel analyses. The electricity generation profiles of the spatially distinct MFC chambers on the array loaded with Shewanella oneidensis MR-1 differed by less than 8%. A screening of environmental microbes using the MFC array identified an isolate displaying 2.3-fold higher power than the S. oneidensis MR-1 reference strain, validated using a conventional MFC.