Document Type
Article
Publication Date
10-2022
Keywords
electrochemical immunosensor; rapid detection; activated biochar; biosensor; Escherichia coli O157:H7
Abstract
E. coli O157:H7, one of the major foodborne pathogens, can cause a significant threat to the safety of foods. The aim of this research is to develop an activated biochar-based immunosensor that can rapidly detect E. coli O157:H7 cells without incubation in pure culture. Biochar was developed from corn stalks using proprietary reactors and then activated using steam-activation treatment. The developed activated biochar presented an enhanced surface area of 830.78 m2/g. To develop the biosensor, the gold electrode of the sensor was first coated with activated biochar and then functionalized with streptavidin as a linker and further immobilized with biotin-labeled anti-E. coli polyclonal antibodies (pAbs). The optimum concentration of activated biochar for sensor development was determined to be 20 mg/mL. Binding of anti-E. coli pAbs with E. coli O157:H7 resulted in a significant increase in impedance amplitude from 3.5 to 8.5 kΩ when compared to an only activated biochar-coated electrode. The developed immunosensor was able to detect E. coli O157:H7 cells with a limit of detection of 4 log CFU/mL without incubation. Successful binding of E. coli O157:H7 onto an activated biochar-based immunosensor was observed on the microelectrode surface in scanning electron microscopy (SEM) images.
Citation
Sobhan, A., Jia, F., Kelso, L. C., Biswas, S. K., Muthukumarappan, K., Cao, C., Wei, L., & Li, Y. (2022). A Novel Activated Biochar-Based Immunosensor for Rapid Detection of E. coli O157:H7. Biosensors, 12 (10), 908. https://doi.org/10.3390/bios12100908
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
