An innovative reactor-type biosensor for BOD rapid measurement

Area of Science:

• Environmental Science
• Analytical Chemistry
• Biotechnology

Background:

• Biochemical oxygen demand (BOD) is crucial for assessing water and wastewater organic pollution.
• Traditional BOD biosensors face limitations in biomass quantity adjustment and detection limits due to membrane-type bio-elements.

Purpose of the Study:

• To develop a novel reactor-type biosensor for rapid BOD measurement.
• To enhance sensitivity, precision, and lifespan of BOD biosensors using immobilized microbial cell (IMC) beads.

Main Methods:

• Development of a reactor-type biosensor utilizing IMC beads in a completely mixed reactor.
• Free suspension of IMC beads to reduce mass transfer resistance for dissolved oxygen and organic compounds.
• Comparison with traditional membrane-type BOD biosensors to address biomass quantity and stability issues.

Main Results:

• The novel biosensor demonstrated significantly increased response sensitivity and detection precision.
• The IMC beads maintained bioactivity for approximately 70 days with daily use.
• Repeatability and reproducibility were within acceptable limits (+/-6.4% and +/-5.0% standard deviation).

Conclusions:

• The developed reactor-type BOD biosensor offers a rapid, sensitive, and stable method for water quality monitoring.
• The use of IMC beads overcomes limitations of traditional membrane-based sensors.
• This technology meets the requirements for rapid BOD measurement in environmental analysis.