A sandwich-type electrochemical immunosensor for detecting CEA based on CeO₂-MoS₂ absorbed Pb²

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Biomedical Engineering

Background:

• Carcinoembryonic antigen (CEA) is a significant biomarker for various cancers.
• Sensitive and reliable detection methods for CEA are crucial for early diagnosis and monitoring.
• Existing detection methods may face limitations in sensitivity, stability, or cost-effectiveness.

Purpose of the Study:

• To develop a novel sandwich-type electrochemical immunosensor for sensitive carcinoembryonic antigen (CEA) detection.
• To utilize gold nanoparticles (Au NPs) and a molybdenum disulfide-Cerium oxide (CeO2-MoS2) nanohybrid for enhanced sensor performance.
• To validate the sensor's analytical performance and applicability in real serum samples.

Main Methods:

• Fabrication of a sandwich-type immunosensor using gold nanoparticles (Au NPs) as a platform for primary antibody (Ab1) immobilization.
• Synthesis of a CeO2-MoS2 nanohybrid to act as a carrier for lead ions (Pb2+) and secondary antibody (Ab2), forming a nanoprobe.
• Detection of CEA antigen via square wave voltammetry (SWV) by measuring the electrical signal of Pb2+ released from the nanoprobe.

Main Results:

• The developed electrochemical immunosensor demonstrated excellent analytical performance.
• The sensor achieved a wide detection range of 0.001-80 ng/mL for CEA.
• A low detection limit of 0.3 pg/mL (S/N=3) was obtained, with good selectivity and stability.

Conclusions:

• The proposed electrochemical immunosensor offers a sensitive, selective, and stable method for CEA detection.
• The integration of Au NPs and CeO2-MoS2 nanohybrid provides a robust platform for biosensing applications.
• The sensor successfully detected CEA in human serum, indicating its potential for clinical diagnostics.