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Updated: May 18, 2026
07:28
Measurement of Bioelectric Current with a Vibrating Probe
Published on: January 4, 2011
A novel bioelectrochemical BOD sensor operating with voltage input.
Oskar Modin1, Britt-Marie Wilén
1Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Sven Hultins gata 8, 41296 Gothenburg, Sweden. oskar.modin@chalmers.se
Water Research
|October 2, 2012
Summary
A new bioelectrochemical sensor offers a faster, more robust alternative to traditional Biochemical Oxygen Demand (BOD) testing. This improved microbial fuel cell (MFC) design overcomes limitations for efficient wastewater analysis.
Area of Science:
- Environmental Science
- Electrochemistry
- Biotechnology
Background:
- Biochemical Oxygen Demand (BOD) is crucial for wastewater treatment plant design and performance assessment.
- Conventional BOD measurement is time-consuming (5-7 days) and requires skilled personnel.
- Microbial Fuel Cells (MFCs) offer a bioelectrochemical alternative for BOD sensing.
Purpose of the Study:
- To develop a novel bioelectrochemical BOD sensor overcoming limitations of existing MFC designs.
- To enhance sensor robustness and simplify operation for practical wastewater analysis.
- To improve the efficiency and applicability of BOD measurement.
Main Methods:
- Development of a bioelectrochemical BOD sensor utilizing applied external voltage.
- Omission of the ion exchange membrane to prevent pH shifts in low alkalinity wastewaters.
- Calibration using acetate as a BOD source in an aerated nutrient medium.
Main Results:
- A linear correlation (R² = 0.97) was achieved for BOD concentrations from 32 to 1280 mg/L within 20 hours.
- A reaction time of 5 hours enabled BOD measurement up to 320 mg/L (R² = 0.99).
- The sensor successfully analyzed propionate, glucose, and ethanol after acclimation to acetate.
Conclusions:
- The developed sensor design is more robust and simpler than conventional MFCs.
- The sensor effectively overcomes limitations of high internal resistance and pH shifts.
- This technology presents a promising advancement for efficient and reliable BOD monitoring.
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