Nanoimprinted optical fibres: Biotemplated nanostructures for SERS sensing

Area of Science:

• Nanotechnology
• Materials Science
• Biophotonics

Background:

• Optical fibre sensors are crucial for in situ chemical monitoring.
• Surface-enhanced Raman scattering (SERS) enhances detection sensitivity.
• Existing SERS sensor fabrication can be complex and costly.

Purpose of the Study:

• To develop a cost-effective and high-resolution method for fabricating optical fibre SERS sensors.
• To leverage biological nanostructures for SERS sensor design.
• To demonstrate the efficacy of these sensors for detecting low chemical concentrations.

Main Methods:

• Utilized nanoimprint lithography to replicate cicada wing nanostructures.
• Applied these nanostructures to the end faces of silica optical fibres.
• Coated the nanoarrays with silver to achieve SERS activity.
• Tested sensor performance using thiophenol and rhodamine 6G analytes.

Main Results:

• Successfully fabricated SERS-compatible nanoarrays on optical fibres.
• Collected strong SERS spectra from test analytes.
• Demonstrated effective sensing via direct endface illumination and through-fibre interrogation.
• Achieved high-resolution and sensitive chemical detection.

Conclusions:

• The biotemplating approach offers a scalable and low-cost method for optical fibre SERS sensor fabrication.
• This technology enables sensitive, in situ monitoring of low chemical concentrations.
• Combines biological inspiration with advanced nanofabrication for high-performance sensing applications.