Gold Nanorods Enable Rapid and Label-Free SARS-CoV‑2 Detection through LAMP Assay

Area of Science:

• Plasmonics and Nanomaterials
• Biotechnology and Biosensing
• Molecular Diagnostics

Background:

• Noble metal nanoparticles exhibit localized surface plasmon resonance (LSPR), enabling their use in biosensors.
• Gold nanorods (AuNRs) offer enhanced plasmonic properties due to their anisotropic shape, improving sensitivity.
• Existing SARS-CoV-2 detection methods can be time-consuming and prone to errors.

Purpose of the Study:

• To develop a rapid and direct biosensing approach for detecting SARS-CoV-2 genetic material.
• To utilize gold nanorods (AuNRs) as transducers for signal generation.
• To integrate loop-mediated isothermal amplification (LAMP) with a custom depolarized dynamic light scattering (DDLS) apparatus for enhanced detection.

Main Methods:

• Employing gold nanorods (AuNRs) as transducers to generate dynamic light scattering signals.
• Utilizing loop-mediated isothermal amplification (LAMP) for amplifying SARS-CoV-2 genetic material.
• Capturing amplified signals with a custom-built depolarized dynamic light scattering (DDLS) apparatus for direct detection.

Main Results:

• Achieved direct detection of SARS-CoV-2 amplicons within a 20-minute reaction time.
• Demonstrated clear discrimination between negative and positive samples, including clinical specimens.
• The integrated AuNR-LAMP-DDLS platform showed high sensitivity and efficiency.

Conclusions:

• The developed AuNR-based biosensor integrated with LAMP and DDLS offers an efficient, rapid, and highly sensitive diagnostic platform for SARS-CoV-2.
• This approach significantly reduces detection time compared to traditional methods.
• The method shows strong potential for reliable clinical diagnostics.