Sensitive Detection of SARS-CoV-2 Using a Novel Plasmonic Fiber Optic Biosensor Design

Area of Science:

• Optoelectronics
• Nanotechnology
• Biosensing

Background:

• The COVID-19 pandemic necessitates rapid and sensitive diagnostic tools.
• Existing biosensors face challenges in sensitivity and reproducibility for viral detection.
• Fiber optic-based plasmonic sensors offer potential for enhanced detection capabilities.

Purpose of the Study:

• To theoretically investigate a novel fiber optic-based plasmonic biosensor for sensitive SARS-CoV-2 detection.
• To achieve reliable, sensitive, and reproducible detection of the virus.
• To enhance molecular adsorption and ligand binding for improved sensing.

Main Methods:

• Proposed a fiber optic plasmonic biosensor configuration utilizing Ag-Au alloy nanoparticle films.
• Incorporated a graphene layer to promote molecular adsorption.
• Utilized a thiol-tethered DNA layer as a specific ligand for SARS-CoV-2 detection.
• Theoretically analyzed sensor performance, including sensitivity and resolution, comparing it with other sensor designs.

Main Results:

• The proposed biosensor configuration demonstrated superior sensitivity (7100 nm/RIU).
• Achieved a good figure of merit (FOM = 38.88) and signal-to-noise ratio (SNR = 0.388).
• Parametric study investigated the impact of graphene layers and nanoparticle size on sensor performance.

Conclusions:

• The novel fiber optic plasmonic biosensor with graphene and DNA ligands shows significant promise for sensitive SARS-CoV-2 detection.
• The integrated approach offers considerable improvements over existing sensor configurations.
• This theoretical insight provides a strong foundation for developing advanced diagnostic tools for infectious diseases.