Impedimetric biosensor based on cell-mediated bioimprinted films for bacterial detection

Area of Science:

• Electrochemistry
• Materials Science
• Biotechnology

Background:

• Marine environments face threats from pathogens like sulfate-reducing bacteria (SRB).
• Developing selective and sensitive detection methods for SRB is crucial for environmental monitoring and public health.
• Bioimprinting offers a promising approach for creating specific recognition sites for target analytes.

Purpose of the Study:

• To synthesize bacteria-mediated bioimprinted films for the selective detection of marine pathogen SRB.
• To optimize electrodeposition conditions for creating a robust RGSs-CS hybrid film platform.
• To evaluate the electrochemical performance and selectivity of the developed impedimetric sensor.

Main Methods:

• Electrodeposition of chitosan (CS) doped with reduced graphene sheets (RGSs) onto an indium tin oxide electrode.
• Bacteria-mediated bioimprinting using SRB as templates, followed by template removal with acetone.
• Electrochemical impedance spectroscopy (EIS) for sensor characterization and SRB quantification.

Main Results:

• Optimized RGSs-CS hybrid films exhibited excellent electrochemical performance.
• A linear correlation was established between charge transfer resistance (ΔR(ct)) and SRB concentration (1.0×10^4 to 1.0×10^8 cfu/mL).
• The impedimetric sensor demonstrated good selectivity for SRB based on size and shape.

Conclusions:

• Bacteria-mediated bioimprinting combined with RGSs-CS hybrid films provides a selective and sensitive method for SRB detection.
• The developed sensor shows potential for monitoring marine pathogens.
• Further improvements in selectivity can be achieved by integrating bioimprinting with other bio-recognition elements.