3D printed self-powered MFC microbial fuel cell biosensor
Researchers in Japan have used 3D printing to produce a low cost, self power biosensor that generates its own power.
The team at Ritsumeikan University researchers designed the biosensor for assessing water quality at the input of lakes and rivers.
The team developed a floating microbial fuel cell (FMFC) that floats on the water with a sensor that can track the influx of organic wastewater. The FMFC generates its own power from bacteria and water and was fabricated with a compact structure and low-cost carbon-based materials for both the anode and cathode electrodes.
The anode of the FMFC was filled with soil containing electrogenic bacteria. This allows the FMFC to generate electricity more efficiently by the diverse array of microorganisms in the soil. MFCs generate electricity with the help of electrogenic bacteria that produce an electric current as a result of their biological metabolism. The amount of electricity generated by the MFC is proportional to the concentration of the organic waste that is being consumed by the electrogenic microorganisms.
“We developed a self-powered, stand-alone, floating biosensor based on a microbial fuel cell (MFC) for early organic wastewater detection. The MFC case was fabricated by a 3D printer and the electrodes were fabricated from low-cost carbon-based materials,” said Professor Kozo Taguchi from the College of Science and Engineering, Department of Electrical and Electronic Engineering at Ritsumeikan University, who led the study.
The team added a light-emitting diode (LED) to the floatable biosensor assembly. This LED was able to harness the electricity produced by the electrogenic bacteria and visually indicate the level of organic contamination in the water samples under investigation.
The LED starts flashing when the chemical oxygen demand (COD)—a parameter used to measure the level of organic contaminants in water—exceeded the threshold value of 60 mg/L. In addition, the LED flashes at an increased pace when the COD significantly exceeded the threshold value.
“Because the FMFC biosensor produces its own electricity, it requires no external power supply. Moreover, it can be used in early detection systems that monitor influxes of organic wastewater in freshwater bodies,” said Prof. Taguchi.