关键词: 空芯微结构光纤/
表面增强拉曼/
光纤探针
English Abstract
Raman probe based on hollow-core microstructured fiber
Sheng Zi-Cheng,Wang Teng,
Zhou Gui-Yao,
Xia Chang-Ming,
Liu Jian-Tao,
Li Bo-Yao,
Fan Hai-Xia,
Chen Yun,
Hou Zhi-Yun
1.Guangdong Provice Key Laboratory of Nano-photonic Functional Materials and Devices, South China Normal University, Guangzhou 510006, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 61575066), the Key Program of the National Natural Science Foundation of China (Grant No. 61735005), the Special Fund for Basic Research on Scientific Instruments of the National Natural Science Foundation of China (Grant No. 61527822), the Science and Technology Program of Guangzhou, China (Grant No. 2017KZ010101), and the Project supported by GDUPS (2017).Received Date:13 April 2018
Accepted Date:11 June 2018
Published Online:20 September 2019
Abstract:Surface-enhanced Raman scattering (SERS) technology can effectively enhance the Raman signal of sample molecules. It has a higher sensitivity to detect biomolecule and thus has many potential applications in biochemistry. The combination of hollow-core microstructured fiber and SERS technology not only enables remote real-time and distributed detection, but also can increase the effective action area between the light field and the object to be measured, and further reduce silica glass background signal that is unavoidable in traditional fiber probes. In this paper, the hollow-core microstructure fiber Raman probes with excellent performance are investigated from the aspects of fiber preparation and SERS experi-mental testing. First, we design and manufacture a kind of hollow-core microstructured fiber with multi-bands in the visible and near-infrared wavelength. The fibers show good light guide performance and thus can fully meet the requirements for surface-enhanced Raman excitation and signal transmission. At the same time, the large core size facilitates the coupling of excitation light, and provides enough room for the test object and the light field. Then, this hollow-core microstructured fiber is used in surface-enhanced Raman experiment. A layer of nano-Ag film is modified on the inner surface of the hollow-core microstructure fiber to prepare the SERS probe by the vacuum physical sputtering method, and Rhodamine 6G (R6G) alcohol solutions with different concentrations are prepared by the dilution method. The hollow-core microstructured fiber deposited with the Ag nano-film is immersed in R6G alcohol solution for 2 min. The alcohol solution of R6G is sucked into the air hole of the hollow-core microstructured fiber by the capillary effect. Then this fiber with R6G alcohol solution is placed in a drying oven at 40 ℃ for 3 h until the alcohol solvent in the air hole is completely volatilized. After that, this fiber is taken out and tested under a detection environment full with air. The fiber SERS probes are tested by microscopic confocal Raman spectroscopy, then the Raman spectra of R6G alcohol solvents with different concentrations are obtained. An R6G Raman signal with a concentration as low as 10-9 mol/L is successfully detected on the front side of the probe. In the far-end back-side detection mode, the detected concentration of SERS probe can be less than 10-6 mol/L. The designed hollow-core microstructured fiber probe has a simple structure and is easy to prepare and test. Compared with the traditional optical fiber, it has advantages of large effective area for the test object and the light field, small interference from the silica glass background signal. This hollow-core microstructured fiber probe has wide application prospects in biochemical detection and other fields.
Keywords: hollow-core microstructured fiber/
surface-enhanced Raman scattering/
fiber probe
