Simultaneous detection of SERS and fluorescence using a single excitation for microbead-based analysis

Area of Science:

• Nanotechnology
• Biomolecular Engineering
• Analytical Chemistry

Background:

• Multiplex analysis is crucial for high-throughput biological assays.
• Current methods often require complex instrumentation or multiple excitation sources.
• Developing simple, cost-effective platforms for simultaneous signal detection remains a challenge.

Purpose of the Study:

• To develop a novel barcoding strategy for multiplex analysis.
• To demonstrate simultaneous detection of surface-enhanced Raman scattering (SERS) and fluorescence signals from a single platform.
• To enable simple identification and biomarker detection using functionalized silver microbeads.

Main Methods:

• Silver microbeads (15 microm diameter) were functionalized with benzenethiol (BT) as a Raman tag and cardiac troponin I (cTnI) antibody.
• A single argon laser source (488 nm wavelength) was used for simultaneous excitation of both SERS and fluorescence signals.
• SERS signals served as identification indices, while fluorescence signals indicated molecular interactions.

Main Results:

• Simultaneous SERS and fluorescence signals were successfully detected from the functionalized silver microbeads.
• The SERS signal from BT provided a unique identifier for each microbead.
• The fluorescence signal allowed for specific biomarker (cTnI) detection.

Conclusions:

• The developed method offers a simple and effective barcoding strategy for multiplex analysis.
• Simultaneous dual-signal detection using a single excitation source simplifies assay procedures.
• This approach holds promise for applications in diagnostics and high-throughput screening.