Preparation Of Functionalized Gold Nanoparticles And Its Application In The Detection Of Biological Samples

Since Nanotechnology as a new technology, regarding a frontier and hot issue inscientific research and application fields, has been invented at the end of the1980s. Aunanoparticles (Au NPs) provide a lot of means and opprotunities in various fields ofchemistry, physics, material science, life science, electronics and photonics, due totheir unique physical and chemical properties. In this paper, the functionlized Au NPswas synthesized by a variety of methods. And the properties of the functionlized AuNPs was characterized IR spectroscopy (IR), UV-vis Spectrophotometry (UV),Transmission Electron Microscope (TEM) and Cyclic voltammograms (CVs), andachieved a high sensitivity, the quantitative characteristics of the photochromicthrombin detection and electrochemical dopamine detection method.First, the preparation methods of Au NPs were described by hydrothermalmethod, ligand exchange and phase transfer prepared. The properties of Au NPs havebeen characterized by TEM, UV and CVs. A ferrocene-functionalized andwater-soluble Au NPs (Fc/nanoAu) were synthesized by the ligand-exchangemethod．And the properties of the ferrocene-functionalized Au NPs have beencharacterized by IR, UV, TEM and CVs.The second, we studied a compound based on Au NPs N-hydroxyethyl-3,3-dimethyl-6-Nitroindoline spiropyran labeled component and higher sensitivity of thephotochromic DNA biosensors. The thrombin was achieved Indirect quantitative by a color change of compound under the conditions of UV irradiation or acidified solution.The linear range of detection of thrombin is1to2orders of magnitude, the detectionlimit is6.52×10-12mol/L (3σ).The third, the Fc(CH2)6S/Au NPs was synthesized by one-step phasetransfermethod in a liquid-liquid system and characterized using TEM, UV and IR.The proposed method dramatically enhanced catalytic effect towards theelectrochemical oxidation of dopamine (DA) and good charge-transport characteristics.An Excellent linearity was found within the range between1.25×10-3and1.0×10-9molL1and the detection limit was5.7×1010mol L1. Interference from AA wasefficiently eliminated and the electrodes had excellent sensitivity, selectivity, stabilityand reproducibility in the determination of DA.