Development of Guided-Mode-Resonance Optical Biosensors with Gold Nano-Particles
| Autor: | Huang, Jian-Zhi, 黃建誌 |
|---|---|
| Rok vydání: | 2019 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 107 The primary goal of this research is to enhance the performance of guide-mode resonance (GMR) biosensors by using the particle plasma resonance (PPR) effect. This research first establishes a three-dimensional guide-modal resonance biosensor model to analyze the optical properties by parametric study to maximize the performance of biosensors. The simulation results are verified by experiments. A three-dimensional finite element method (FEM) model of guide-mode resonance biosensors with gold nanoparticles (AuNPs) is established in this research. The simulation results indicate that the PPR effect will increase the sensitivity of GMR biosensors by increasing the area of the evanescent wave in the analyte. However, when the GMR and PPR effects are coupled at the resonant wavelength, although the electrical field near the surface of grating can be considerably enhanced, quality factor of GMR modes significantly drops due to the considerable absorption of AuNPs Refractive index experiments were carried out with different conditions to compare with the theoretical simulations, and good agreements were found. First, the optimal incident angle to achieve highest sensitivity is found to be 15 degree. The sensitivity of GMR biosensors based on the intensity measurement system can raise by a factor of 56.525% due to the modification of AuNPs on the surface of grating. Second, from the simulation results, GMR biosensors under the front-side incidence condition exhibit better sensitivity than these under back-side incidence condition. Third, the resonant wavelength of GMR modes can be engineered by changing the period of grating to match the PPR resonant wavelength. Finally, the surface sensitivity model provides a basis for comparing the performance of GMR biosensors with different biomolecules. These results provide a new pathway to enhance the performance of GMR biosensors for highly sensitive chemical analysis and biomedical detection. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|