Single-Exosome SERS Detection by Means of a Flexible Metasurface

Area of Science:

• Nanotechnology
• Spectroscopy
• Biomedical Engineering

Background:

• Exosomes are crucial biomarkers for disease detection.
• Current methods for exosome detection and analysis face limitations in sensitivity and specificity.
• Developing advanced analytical tools for single exosome characterization is essential.

Purpose of the Study:

• To develop a flexible metasurface for sensitive detection of single exosomes.
• To enable detailed spectroscopic analysis of individual exosomes using surface-enhanced Raman scattering (SERS).
• To integrate this technology into Lab-On-Chip systems for automated analysis.

Main Methods:

• Fabrication of a flexible silver nanofilm metasurface using holographic lithography.
• Utilizing surface-enhanced Raman scattering (SERS) for exosome detection.
• Employing atomic force microscopy (AFM) and scanning spreading resistance microscopy (SSRM) for characterization.

Main Results:

• Demonstrated detection of single exosomes via SERS on the flexible metasurface.
• Achieved high electromagnetic field enhancement due to plasmon resonance.
• Successfully obtained and assigned SERS spectra for individual exosomes from HEK293T cells.
• Highlighted the spatial complementarity of the metasurface to exosomes.

Conclusions:

• The flexible metasurface offers a promising platform for sensitive single exosome detection and SERS analysis.
• This technology can be integrated into automated Lab-On-Chip systems.
• The developed method allows for distinguishing and characterizing individual exosomes.