A novel split PEC sensor based on magneto-optic nanostructure and photocurrent polarity switching strategy

Area of Science:

• Electrochemistry
• Nanotechnology
• Biomedical Engineering

Background:

• Photoelectrochemical (PEC) sensors offer low cost and high sensitivity but suffer from time-consuming modifications and interference.
• Conventional PEC sensor fabrication is complex and prone to instability.
• Existing methods struggle with complex samples, leading to inaccurate detection.

Purpose of the Study:

• To develop a novel, stable, and highly sensitive PEC sensor for Carcinoembryonic antigen (CEA) detection.
• To overcome the limitations of conventional PEC sensors, including complex fabrication and susceptibility to interference.
• To introduce a polarity inversion strategy for enhanced PEC sensing performance.

Main Methods:

• Fabrication of a split magnetic separation PEC sensor using Fe3O4@SiO2@CdS magnetic nanostructures.
• Utilizing ZnO/CuO as a marker on DNA2 molecules for signal amplification.
• Employing a photocurrent polarity switching strategy for signal detection.

Main Results:

• The developed sensor achieved sensitive detection of CEA within a range of 1-10000 pg/mL.
• A low detection limit of 0.34 pg/mL for CEA was established.
• The sensor demonstrated high speed, efficiency, sensitivity, specificity, and stability.

Conclusions:

• A split PEC immunosensor based on magneto-optic nanostructure and polarity switching was successfully developed.
• The magnetic nanostructure Fe3O4@SiO2@CdS-DNA1 enabled efficient magnetic separation and signal generation.
• The developed platform provides a new approach for PEC sensing and can be extended to detect other biomarkers.