Dual-functional optical fiber SERS probe with high sensitivity and self-cleaning

Area of Science:

• Nanotechnology
• Spectroscopy
• Materials Science

Background:

• Surface-enhanced Raman scattering (SERS) offers high sensitivity for molecular detection.
• Developing reusable and self-cleaning SERS probes remains a challenge for practical applications.
• Optical fiber-based SERS probes provide a versatile platform for remote and in-situ sensing.

Purpose of the Study:

• To develop a highly sensitive and reusable SERS probe using silver nanocubes (Ag NCs) on a tapered optical fiber.
• To demonstrate the self-cleaning capability of the SERS probe through laser irradiation.
• To evaluate the probe's performance in detecting various analytes for potential biomedical and environmental monitoring.

Main Methods:

• Silver nanocubes (Ag NCs) were synthesized via a polyol method.
• Ag NCs were uniformly deposited onto a tapered optical fiber using laser-induced deposition.
• The SERS probe's sensitivity, reusability, and molecule recognition capabilities were experimentally validated.

Main Results:

• The SERS probe achieved a high sensitivity for Rhodamine 6 G (R6 G) detection down to 10^-11 mol/L.
• An analytical enhancement factor (AEF) of 6.77 × 10⁸ was recorded.
• The probe demonstrated stable Raman signals over four cleaning cycles using laser irradiation and successfully detected multiple analytes including R6 G, malachite green (MG), crystal violet (CV), uric acid, and uremic acid.

Conclusions:

• The developed Ag NCs-based tapered optical fiber SERS probe exhibits excellent sensitivity and self-cleaning functionality.
• The probe's reusability and ability to detect multiple analytes highlight its potential for cost-effective and sustainable sensing solutions.
• This work offers significant promise for advancing SERS technology in critical areas such as biomedical diagnostics and environmental surveillance.