Surface Coating and Bioconjugation of Gold Nanorod via Ultrasmall Fluorescent Gold Nanoclusters
| Autor: | Zhi-Wei Chen, 陳致瑋 |
|---|---|
| Rok vydání: | 2014 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 102 In recent years nanotechnology is flourishing, gold based materials have excellent biocompatibility. By tuning the particle size and shape, a diverse range of applications are readily available. For a certain range of frequency of an incident light irradiated upon gold nanorod (AuNR), surface plasmon resonance (SPR) effect can be produced. The SPR effect was utilized to acquire the absorption bands between visible and near-infrared light (NIR) of the AuNR for biomedical, optical electronics, and imaging applications. Capping agents like cetyltrimethylammonium bromide (CTAB) enhances the stability of gold nanorod but the problem is its cytotoxicity, so CTAB was replaced by a surface modification method using polyelectrolyte coating, silica shell, and dative bonding of thiol group molecules or hydrophilic and hydrophobic phospholipid coating. Most modifications to overcome gold nanorod surface problems took long reaction time and it influenced the original optical properties of gold nanorod. This research proposed a novel, simple, electrostatic force based principle approach to modify the surface of the AuNR, the surface of gold nanoclusters (AuNCs@DHLA) contain carboxyl groups which are anionic and were used to attach on the AuNR’ cationic surface, AuNCs@DHLA is more efficient than other gold nanoclusters. To verify the nanoparticle specific absorption wavelength, structure, functionalization and mobility status; UV-Vis absorption spectra, transmission electron microscopy and agarose gel electrophoresis was done respectively. The commercialized mercapto compounds (N, N, N-trimethyl (11-mercaptoundecyl) ammonium chloride, TMAC) replaced the AuNR’ CTAB on the surface, then the attachment efficiency and bio-functionalization of TMAC to gold nanoclusters was analyzed. The attachment efficiency between 6 nm nanoparticles and AuNCs@DHLA was compared. As a result, AuNCs@DHLA provides superior unit charge density than 6 nm gold nanoparticles, carboxylic groups attached more efficiently on AuNR compared to other gold nanoclusters (AuNCs@BSA, AuNCs@GSH). Finally, AuNCs@DHLA was attached on the gold nanorod surface containing CTAB or TMAC, and a variety of PEGylation was done. As a result, better biological interface can be provided in a variety of applications. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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