A two-channel bacteria-based biosensor for water quality monitoring

We created a dual-channel bacteria-based biosensor for sensitive and reliable monitoring of toxic substances in water. We utilized microbial fuel cell (MFC) technology as a biosensor for the detection of water toxicity. A broad range of toxic components can inhibit bacterial metabolic activity, generating a distinct change in the current output of the MFC-based biosensor. The biosensor consisted of two 90μL single-chambered MFCs (detection and reference) with air-cathodes, which significantly simplifies the device configuration. The reference channel sensor was to calibrate the system for environmental changes (e.g., temperature, pressure, viscosity, pH, and non-specific binding) that influence the bacterial metabolisms, thus improving the accuracy of the measurement. In addition, the small-scale MFC biosensor produced favorable conditions for high sensitivity by reducing the internal resistance and increasing mass transfer in the micro-sized chamber.