An optic-fiber graphene field effect transistor biosensor for the detection of single-stranded DNA

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Analytical Chemistry

Background:

• Conventional biosensors often rely on single detection methods, limiting reliability and accuracy.
• Developing integrated biosensors with multiple read-out mechanisms is crucial for enhanced performance.
• Graphene field-effect transistors (GFETs) offer high sensitivity for biomolecule detection.

Purpose of the Study:

• To develop an integrated optical/electrical double read-out biosensor for detecting target single-stranded DNA (tDNA).
• To combine GFET and fluorescence sensing principles on a single optic fiber platform.
• To improve the accuracy and reliability of DNA detection through a dual sensing strategy.

Main Methods:

• Constructed a GFET on an optic fiber end face with gold electrodes and a graphene film.
• Immobilized probe aptamers on graphene for tDNA capture and used graphene oxide for fluorescence quenching.
• Integrated a fluorescence biosensor with the GFET for a dual read-out system.

Main Results:

• The integrated dual biosensor demonstrated satisfactory sensitivity for DNA detection.
• Synchronous detection via fluorescence and FET methods provided reliable results.
• The dual sensing approach significantly improved the accuracy and reliability compared to single-sensing methods.

Conclusions:

• The proposed technique offers a novel biosensor for single-stranded DNA detection.
• This work presents a viable strategy for designing multi-sensing integrated biosensors.
• The dual read-out mechanism enhances the trustworthiness of biosensing results.