Related Experiment Video
Updated: Aug 28, 2025
08:12
Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing
Published on: March 13, 2013
12.9K
Molecular trace detection in liquids using refocusing optical feedback by a silver-coated capillary
Chen Kang1, Zhoutao Sun1, Xiaohui Fang1
1Institute of Information Photonics Technology, Faculty of Science, Beijing University of Technology Beijing 100124 China fangxh@bjut.edu.cn zhangxinping@bjut.edu.cn.
Nanoscale Advances
|September 22, 2022
Summary
A novel silver-coated capillary platform enhances surface-enhanced Raman scattering (SERS) detection of trace molecules in liquids. This 3D SERS substrate achieves high sensitivity and homogeneity for advanced optofluidic systems.
Area of Science:
- Analytical Chemistry
- Materials Science
- Optics
Background:
- Surface-enhanced Raman scattering (SERS) offers high sensitivity and rapid detection.
- 3D SERS platforms enhance molecular interaction and liquid sample analysis.
- Capillary-based systems present opportunities for integrated optofluidic devices.
Purpose of the Study:
- To develop a novel 3D SERS-active platform using a silver-coated capillary.
- To enhance the sensitivity and homogeneity of SERS detection for liquid samples.
- To explore the potential of this platform in optofluidic integrated systems.
Main Methods:
- Silver coating on the outer wall of a capillary via the silver mirror reaction.
- Protection of the silver film using a PDMS coating.
- Characterization of SERS performance, including enhancement factor and detection limit.
Main Results:
- Achieved a high enhancement factor of 10^8 and a detection limit of 10^-10 M for rhodamine 6G.
- Demonstrated high SERS intensity homogeneity (RSD < 7%) across the liquid channel.
- Reported a detection limit of 10^-8 M when coupled with a multimode fiber.
Conclusions:
- The silver-coated capillary serves as an effective 3D SERS substrate for sensitive and homogeneous detection.
- The platform simplifies optical coupling and liquid handling, reducing experimental constraints.
- This technology shows significant promise for future optofluidic integrated systems.
