以奈米光柵耦合表面電漿子共振增強拉曼散射於生醫感測之應用

Abstract

noneEnormous interest in biosensors has drawn considerable attention among researchers, given its wide applications in clinical treatment, biomedical technology, healthcare, pharmaceuticals, and food science. Specifically, the surface plasmon resonance (SPR) technique has served as a robust biosensor, and its versatile principle makes SPR a widely utilized sensing method extensively employed to study biomolecular interactions, material properties, and chemical processes. In this study, we designed a grating-coupler SPR system integrated into a preconfigured Raman spectrometer system to measure the Raman enhancement on Rhodamine 6G adsorbed on two different structures: linear and circular nanograting. Experiments show that SPR-Raman enhancement is achieved for linear and circular structures by approximately 2.14 × 103 and 2.46 × 103, respectively, when the sample is simultaneously excited by the Raman probe at normal incidence and the SPR system at resonance angle. The propagating SPPs allow the sample to be in an excited state, providing an enhanced evanescent field, which is then coupled with the localized SPPs upon Raman excitation and measurement. These results suggest that SPR can be used to enhance the Raman signal of an analyte and improve detection.