| Summary: | 碩士 === 國立臺灣大學 === 生醫電子與資訊學研究所 === 104 === Surface plasmon resonance is a hot research topic in nanooptics field recently. Due to its label-free, non-invasive and highly sensitive merits, localized surface plasmon resonance based sensing techniques have been widely utilized in chemical or biosensing applications with simplified optical settings and real-time detection capability. In this paper, we developed a simple and fast nanostructure fabrication method using electron beam evaporation deposition and rapid thermal annealing (RTA) treatment to fabricate a large-area (2cm x 2cm) biosensor utilizing localized surface plasmon resonance (LSPR) nanoplasmonic effects. To get the best LSPR sensing performance of the gold nanostructure, we adjusted three fabrication conditions: (1) deposition thickness; (2) annealing temperature and (3) the annealing time. We then observed the absorbance spectrum profile and surface morphology using the UV-VIS spectrometer and atomic force microscopy (AFM). Based on the results, we discovered that the fabrication conditions at 6-10nm gold deposition under 900°C RTA treatment for 5 minutes shows sharper and stronger absorbance spectrum. We then test the sensitivity of these sensor by using glucose-water solution of different concentration. We found out that the 10nm gold chip shows the highest sensitivity 161.5 nm/RIU and holds a fine uniformity (peak wavelength variation < 1%). To study the electromagnetic field and the absorbance spectrum of the arbitrary-shaped and random-distributed nanoparticles fabricated by RTA treatment, we constructed an effective nanostructure array based on AFM scanned results and used a finite-element method (FEM) software COMSOL to numerically analyze the dependence of absorbance spectrum on the different height of nanoparticles for future alternation of annealing parameters. Finally, we integrated this LSPR sensor with a commercial microfluidic channel as an immunoanalysis platform to achieve dynamic and continuous detection of multiple cytokines with reduced sample volume (45μl) while still demonstrating fine specificity and sensitivity. In the future, if we can minimize the optical structure and integrates it into the system, we will be able to realize the point-of-care testing approach.
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