Gold Nanoparticles/TiO2 Nanocomposite Film by Self-Assembly Method for Glucose Biosensor

• Main Authors: YU, YI-KENG, 余宜耿
• Other Authors: CHOU, HSUEH-TAO
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/64f98a

碩士 === 國立雲林科技大學 === 電子工程系 === 106 === In this study, gold nanoparticles is successfully prepared by using photochemical method. AuNPs is modified on ITO and TiO2 film using the self-assembly method with APTES for the self-assembly time of 4 hours, 8 hours, and 12 hours, where APTES is used as a linker molecules. The particles diameter was measured by using transmission electron microscope(TEM). The morphology was measured by using field-emission scanning electron microscope (FE-SEM) and atomic force microscope (AFM). The optical properties and glucose solution are measured by using UV-Visible spectroscopy. The sensing characteristics of the biosensor have been analyzed for the sensitivity, linearity and electrochemical properties by using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) measurement systems. The result shows AuNPs/TiO2 nanocomposite film had a good optical properties. When AuNPs is modified on TiO2 films, the photcatalytic activity of TiO2 can enhance optical properties. In optical properties measurement, LSPR sensor based on AuNPs/TiO2 nanocomposite film with a self-assembly time of 12 hours have good sensitivity and linearity for detecting the environment of different refractive indices are 58.4 nm and 0.995, respectively. After detecting glucose solution, the results show a good sensitivity of 0.44 nm/mM and a limit of detection of 3.47 mg/dl (0.197 mM). In electrical properties measurement, the nafion is applied as an immobilization material due to the high chemical stability and biocompatibility. The enzyme composite solution was dropped on the AuNPs /ITO electrodes and AuNPs/TiO2/ITO electrodes to form glucose biosensor. The glucose biosensor of Nafion/GOx-AuNPs/ITO electrode has a good sensitivity is 8.674 μA/mM．cm2, a good linearity of 0.946, and a limit of detection of 7.3 mg/dl (0.394mM) , which are better than the previous results in our group. The sensitivity, linearity, and limit of detection for the glucose biosensor of Nafion/GOx-AuNPs/TiO2/ITO electrode are 3.438 μA/mM．cm2 , 0.945, and 17.7 mg/dl(0.956mM), respectively. In the interference measurement, the different interferences are detected by using Nafion/GOx-AuNPs-APTES/ITO electrode. The interference effects for 0.1 mM ascorbic acid, 0.4mM uric acid, and 0.2 mM acetaminophen are 2.6 %, 4.9 %, 0.3 % , respectively.