| Chapter 1:The classification, characteristics and synthesis of nanomaterials are depicted in brief. The optical properties and analytical application of noble metal nanoparticles, particularly gold nanoparticles, are reviewed in detail.Chapter 2:Firstly, per-iodo- and per-thiol-β-cyclodextrin, that is, derivatives ofβ-cyclodextrin, were synthesized. Then, gold nanoparticles monolayer protected with per-thiol-β-cyclodextrin as a ligand or stable substrate was prepared, in which HAuCl4-3H2O was reduced by sodium triacetoxyborohydride. The nanoparticles were characterized by means of UV-visible absorption, FTIR, HNMR, Transmission Electron Microscope, Mass Spectroscopy and Thermogravimetric Analysis. Results indicated that the average size of P-cyclodextrin-modified gold nanoparticles is ca.2.7±0.8 run and numbers of gold atom and ligand were calculated to be 147 and 10, respectively.Chapter 3:The interaction of water-solubleβ-cyclodextrin functionalized gold nanoparticles (β-CD-Au NPs) with L-tyrosine was studied by fluorescence spectroscopy. P-CD-Au NPs as an effective supramolecular host molecule in aqueous solution was found to remarkably quench fluorescence of L-tyrosine at the emission of 305 nm. Owing to the formation of the L-tyrosine-β-CD-Au NPs complex, static quenching involved resulted in the fluorescence quenching. Apparent binding constants and corresponding thermodynamic parameters at different temperatures were calculated by Stern-volmer equation and thermodynamic formula, respectively. Results indicated that hydrophobic interaction and Vader waals forces could be in dominant position in the formation of the complex. Under the optimum conditions, the concentration of L-tyrosine is proportional to decrease of the fluorescence intensity in the range from 0.02 to 1.5μM with the corresponding detection limit (S/N=3) of 1.6 nM and relative standard deviation is 0.3%. The developed method has been successfully employed to the quantitative determination of L-tyrosine in compound amino acid injection, and recovery ranges from 98.6 to 103.1%.Chapter 4:N-Acetyl-L-Cysteine modified gold nanoaprticles with mole ratio from Au/NAC at 1:3 was synthesized, in which HAuCl4·3H2O was reduced by sodium triacetoxyborohydride. The as-prepared gold nanoparticles were soluble and the aqueous solution showed brown. They were chacterized by FTIR and UV-Vis spectroscopy. The fluorescence spectra of gold nanoparticles were also investigated. Experimental results indicated that UV-visible absorption spectra of NAC-Au NPs ranged from ultraviolet to visible regions, fluorescence maximum emission at 730 nm existed in the near IR region and the effect of pH on fluorescence spectra was little. In addition, interaction of water soluble NAC-Au NPs with metal ions containing copper ion, silver ion, mecury ion and lead ion was studied by fluorescence and UV-Vis spectroscopy. The presence of metal ions caused queching to different extent of NIR fluorescence of NAC-Au NPs and effect of pH was investigated, In combination of fluorescence and UV-Vis as well as time-resolved fluorescence measurement, the probably quenching mechanisms from different metal ions were proposed. The experimental results indicated that other coexistent metal ions apart from mercury ion were concealed in the presence of EDTA. Considering the application in the detection of real samples without mercury ions, the detection method of silver ion was developed. The linear range was 0-25μM, and detection limit was 30 nM. The method has been employed to the quantitative determination of silver ion in mianeral water and tap water with recovery in the range from 98 to 105%.
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