A nanostructured cerium oxide film-based immunosensor for mycotoxin detection

Area of Science:

• Nanomaterials Science
• Biosensor Technology
• Analytical Chemistry

Background:

• Ochratoxin-A (OTA) is a harmful mycotoxin requiring sensitive detection methods.
• Existing detection methods for OTA can be time-consuming or lack sensitivity.
• Nanostructured materials offer unique properties for biosensor development.

Purpose of the Study:

• To develop a novel immunoelectrode for sensitive OTA detection.
• To utilize sol-gel-derived nanostructured cerium oxide (nanoCeO2) for enhanced biosensor performance.
• To immobilize antibodies and proteins onto the nanoCeO2 film for specific OTA binding.

Main Methods:

• Fabrication of nanostructured cerium oxide (nanoCeO2) film on an indium-tin-oxide (ITO) coated glass plate using sol-gel method.
• Immobilization of rabbit-immunoglobulin antibodies (r-IgGs) and bovine serum albumin (BSA) onto the nanoCeO2 film.
• Electrochemical characterization and performance evaluation of the fabricated immunoelectrode for OTA detection using techniques like X-ray diffraction (XRD).

Main Results:

• XRD patterns confirmed the formation of CeO2 nanostructures.
• The nanoCeO2 film provided increased electroactive surface area, enhancing r-IgGs loading and electron communication.
• The BSA/r-IgGs/nanoCeO2/ITO immunoelectrode demonstrated a linear range of 0.5-6 ng dl(-1), a low detection limit of 0.25 ng dl(-1), and a fast response time of 30 s.
• High sensitivity (1.27 microA ng(-1) dl(-1) cm(-2)) and a high association constant (Ka, 0.9 x 10(11) l mol(-1)) for OTA were achieved.

Conclusions:

• The developed BSA/r-IgGs/nanoCeO2/ITO immunoelectrode is a promising platform for sensitive and rapid OTA detection.
• Nanostructured cerium oxide enhances the electrochemical performance and affinity of the biosensor.
• This approach holds potential for improved food safety monitoring and mycotoxin analysis.