bioreceptors which comprises an analyte along with different bioreceptors, electronic

systems, transducers, among other components, as seen in Figure 11.7 [49].

Many biological materials are used in the fabrication of biosensors including micro­

organisms (algae, bacteria, and yeast), enzymes, and cells because they can be massively

produced and easier manipulated [50]. The microbial biosensors are a close contact

analytical device between microorganisms and the transducer [50]. Recently, the recovery

of the high-value product of MFC such as biohydrogen and methane has increased at­

tention towards this technology. MFC-based biosensors can be used as an analytical tool

for the measurement of various analytes and parameters that include biochemical oxygen

demand (BOD), chemical oxygen demand (COD), toxicants, and microbial activity [49].

The characteristics of MFC-based biosensors vary according to the substrates, solution,

and can incorporate the use of both bacterial consortia and single strains. In an MFC-

based biosensor device, microorganisms are capable to sense the analyte and give an

equivalent response to its yielded electric current. Electrobiosensors comprise cathode

and anode chambers, and both are separated by a membrane that enables proton ex­

change. The performance of MFC-based biosensors for toxicity detection depends on the

type of electroactive microbes with special properties used in the cell.

11.7 Conclusion

The discovery of many properties of microbial nanowires, and the possibility to modulate

their conductivity can offer a basis for new fields and future research between

FIGURE 11.7

Schematic illustration of typical biosensors and types of bioreceptors and transducers used in the biosensors.

Reprinted with permission [ 49]. Copyright © 2021. MDPI, Article is available under the Creative Commons

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