Wednesday, 1 June 2016: 12:00
Aqua 310 A (Hilton San Diego Bayfront)
Microbial three-electrode cells (M3C) have been widely used as a promising platform for developing biosensors and studying electrochemically active bacteria (EAB). Compared to conventional microbial two-electrode cells (e.g. microbial fuel cells and microbial electrolysis cells), M3Cs can offer more stable and better defined electrochemical environments for various research purposes. This work focuses on developing a microfluidic M3C with micro-liter scale volume by using soft-lithography technology, which has comparable performance as the conventional bench scale M3Cs. In this microfluidic M3C with a build-in three electrode system, laminar flow was exploited to separate the reference electrolyte (0.1 M KCl) from the medium without hindering ion exchange. With the stable and controllable working electrode potential, this device was able to provide a well-defined electrochemical environment for G. sulfurredecens respiration on the electrode. Due to the micro-liter scale volume and a short hydraulic retention time (HRT), fast responses to ferric citrate and formaldehyde with a good reproducibility were achieved. Furthermore, a good linear relationship between the output signal (peak area) and chemicals concentrations was obtained. The microfluidic M3C developed in our work would provide researchers in related areas a versatile platform for biosensor and fundamental EAB study.