In situ microbial fuel cell-based biosensor for organic carbon

Area of Science:

• Environmental Science
• Biotechnology
• Electrochemistry

Background:

• Traditional biological oxygen demand (BOD) testing is crucial for assessing water pollution but is time-consuming and performed ex-situ.
• There is a need for efficient, real-time monitoring systems for wastewater quality.

Purpose of the Study:

• To develop and evaluate a biosensor for online and in-situ monitoring of biodegradable organic content in domestic wastewater.
• To assess the feasibility of using a microbial fuel cell (MFC) based biosensor for this purpose.

Main Methods:

• A BOD biosensor was constructed based on the microbial fuel cell principle.
• The biosensor's performance was tested using domestic wastewater.
• Current density measurements were correlated with BOD5 concentrations under controlled conditions.

Main Results:

• A stable current density of 282±23mA/m² was achieved with wastewater having a BOD5 of 317±15mg O2/L.
• A linear relationship was observed between current density and BOD5 concentration within the range of 17±0.5 to 78±7.6mg O2/L.
• Current generation was influenced by temperature, conductivity, and pH, necessitating correction factors for varying environmental conditions.

Conclusions:

• The developed BOD biosensor shows promise for real-time, in-situ monitoring of wastewater quality.
• The MFC-based approach offers a potentially faster and more efficient alternative to conventional BOD testing.
• Further development and calibration are required for practical application in diverse environmental settings.