Summary: | 碩士 === 國立中興大學 === 化學系所 === 103 === Nanomaterials are very popular in biochemical sensor researches recently. In this study, gold nanoparticle (Au NP) decorated TiO2 nanowire (TiO2 NW) electrode was constructed to immobilize cytochrome c for H2O2 electrochemical biosensors. TiO2 NW has some particularities like its chemical inertness, rigidity, thermal stability, and good biocompatibility;Au NPs also have been attracting attentions for their good biocompatibility, high stability, and easy production. Au NPs act as good electron-transfer site and can easily pierce through the shells of proteins, thus the electron transfer pathway between the active centers inside cytochrome c and the electrode is shortened, promoting the electron-transfer rate. Cyt. c was immobilized on TiO2 by electrostatically interaction which can prevent proteins denaturating due to strong chemical bonding. And the electron-transfer path through one-dimensional structure TiO2 NW can reduce electrical signal loss due to disorderly path .
The surface coverage of cyt. c absorbed on TiO2 NW electrode is 40.5%,and the value is raising to 60.4% when using Au NP/TiO2 NW electrode. In addition, Au NPs also reduce the resistance of electrode and help cyt. c quickly response with H2O2 within 5s. The linear range of H2O2 detection was 0.1mM to 1.2mM . From these experiment results, Au NP/ TiO2 NW electrode will be a promising electrode material for third-generation biosensors.
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