Bipyridinyl-alkyl-thiol capped gold nanoparticles : metal ion sensing and self-assemble properties

• Main Authors: Chi-Wei Kao, 高志瑋
• Other Authors: Wen-jwu Wang
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/50663808935924997622

碩士 === 淡江大學 === 化學學系碩士班 === 97 === Gold nanoparticles solution was prepared by sodium borohydride method. Particle size of 3 nm was characterized by electronic absorption spectra and transmission electron microscopy. A di-thiol compound, bis(12-mercaptododecyl)2,2’-bipyridie-3,3’-dicarboxylate(HSC12EBiox), and a mono-thiol compound, (Methyl)[12-mercaptododecyl]2,2’-bipyridine-3,3’-dicarboxylate (HSC12MEBiox), was synthesized. Functionalized AuNPs containing these agent with/without co-capping agents was prepared and used for metal ion sensing. The co-capping agent is decanethiol or hexanethiol. The AuNPs(3 nm) employed as chromophores were capped with agent through Au–S bonds. If their aggregation were to be driven by the recognition and binding of heavy-metal ions, the color change would allow visual sensing of the ions. Treating of these solutions with Ba2+、Mn2+、Co2+、Ni2+、Cu2+、Ag+、Zn2+、Cd2+、Pb2+ and Hg2+ ion, we found that 3(1-decanethiol)/HSC12EBiox-AuNPs and 1-hexanethiol/ HSC12MEBiox-AuNPs system could successfully detect mercury ion and have high selectivity. The TEM experimental results revealed that the 3DT/HSC12EBiox-AuNPs self-assembly aggregate into soluble 1-D chains in addition of Hg2+. The HT/HSC12MEBiox-AuNPs self-assembly aggregate into soluble larger spherical particles of 100 nm. We unveiled a new homogeneous assay-using bipyridinyl-alkyl-thiol modified AuNPs which has highly selective and sensitive detection of Hg2+ was synthesized. In this study, we took advantage of the aggregation-induced color changes of HSC12EBiox and HSC12MEBiox-functionalized AuNPs in aqueous solutions to develop a highly selective optical sensor for Hg2+.