Single-beam optical trap-based surface-enhanced Raman scattering optofluidic molecular fingerprint spectroscopy detection system

作者：Ning Sun, Gan Yuan, Yujie Wu, Xing Wang, Shen Shen, Yong Zhu, Jie Zhang · 发表于：Opto-Electronic Advances · 年份：2025 · DOI：10.29026/oea.2025.240182 · 被引用次数：23 · 研究领域：Gold and Silver Nanoparticles Synthesis and Applications、Biosensors and Analytical Detection、Microfluidic and Bio-sensing Technologies

In this study, we developed a single-beam optical trap-based surface-enhanced Raman scattering (SERS) optofluidic molecular fingerprint spectroscopy detection system. This system utilizes a single-beam optical trap to concentrate free silver nanoparticles (AgNPs) within an optofluidic chip, significantly enhancing SERS performance. We investigated the optical field distribution characteristics within the tapered fiber using COMSOL simulation software and established a MATLAB simulation model to validate the single-beam optical trap's effectiveness in capturing AgNPs, demonstrating the theoretical feasibility of our approach. To verify the particle capture efficacy of the system, we experimentally controlled the optical trap's on-off state to manage the capture and release of particles precisely. The experimental results indicated that the Raman signal intensity in the capture state was significantly higher than in the non-capture state, confirming that the single-beam optical trap effectively enhances the SERS detection capability of the optofluidic detection system. Furthermore, we employed Raman mapping techniques to investigate the impact of the capture area on the SERS effect, revealing that the spectral intensity of molecular fingerprints in the laser-trapping region is significantly improved. We successfully detected the Raman spectrum of crystal violet at a concentration of 10 −9 mol/L and pesticide thiram at a concentration of 10 −5 mol/L, further demonstrating the ...