利用微生物自身的生理功能制备金属纳米材料是一种简单的，环境友好的、原材料来源丰富的金属纳米材料制备体系（贵金属金、银），实现经济的循环和可持续发展。对材料的形貌、性质和合成机理进行研究，可望有助于目前还处于探索阶段的纳米粒子形成机制；微生物对金属的良好耐受性对发展其在多种金属纳米材料制备方面有更广阔的应用前景。本研究以一株光合细菌RC为还原物，在室温下还原金离子。实验结果表明细菌可以还原金离子得到形貌不同的纳米粒子。pH值低的情况可以形成金纳米片，而中性pH值下形成的都为球形金纳米粒子
The optoelectronic and physicochemical properties of nanoscale matter are size and shape-dependent. So synthesis of gold nanoparticles of different sizes and shapes is of great importance for their applications in optical devices, electronics, biotechnologies and catalysis. Conventional synthetic methods of gold nanoparticls have involved a number of chemical methods. There is an increasing pressure to develop clean, nontoxic and environmentally benign synthetic technologies. Microbial resistance against heavy metal ions has been exploited for biological metal recovery via reduction of the metal ions or formation metal sulfides. So the attractive procedure is using microorganisms such as bacteria and fungi to synthesize gold nanoparticles recently. The use of microorganisms in the synthesis of nanoparticles emerges as eco-friendly and exciting approach. In this study, the bacteria Rhodopseudomonas capsulata was screened and found to successfully produce gold nanopartilcles of different sizes and shapes.
利用细菌RC制备不同形貌的金纳米颗粒
Picture of test tubes containing the bacteriaRCbiomass before (test tube 1) and after 48 h (test tube 2) incubation in an aqueous of AuCl4- solution
TEM images of the gold nanoparticles produced by the reaction of 10-3M aqueous HAuCl4 solution with bacteriaRCbiomass at pH7 and pH4 respectively. The insets show ED pattern of gold nanostructures in the main part of the respective Figure
UV-Vis absorption spectra of gold nanoparticles produced at pH7 (curve1) and pH4 (curve2
Possible mechanisms of gold ions bioreduction
Accepted by Material Letters 2007
研究进展