Authors: R. Bhattacharya, C.R. Patra, S. Wang, L. Lu, M.J. Yaszemski, D. Mukhopadhyay and P. Mukherjee
Affilation: Mayo Clinic, United States
Pages: 833 - 836
Keywords: protein, assembly, gold nanoparticles, template
Nanoparticles of metals possess unique chemical, electronic, optical and magnetic properties from their bulk counterpart because of the quantum size effects. The spatial orientation and arrangement of nanoparticles is important in the realization of technologically useful nanoparticle-based materials. Nevertheless, the assembly of nanoparticles into defined arrays remains a challenge. There are numerous reports to assemble gold nanoparticles in a defined manner. In all of these reports the linker molecules were generally added to a preformed gold nanoparticle solution for their assembly. Here a facile process for the assembly gold nanoparticles in a linear fashion has been described using proteins as templates. The presence of proteins during the reduction of gold salts by sodium borohydride directs the assembly of gold nanoparticles in a linear fashion when cooled to –800 C followed by thawing at room temperature. Similar results were obtained by cooling at –20 C, whereas no assembly was observed when cooled at 00C. Assembly was also not observed when proteins are added to as synthesized gold nanoparticles solution. Therefore, interaction of gold salts with the protein before the reduction is essential for such an assembly process. The assembled products thus obtained were characterized using transmission electron microscopy (TEM), UV-visible spectroscopy (UV-Vis) and thermogravimetric analysis (TGA).