微生物细胞外还原制备纳米粒子过程中的电子传递机制研究

Selecting soil samples from water treatment workshop of smelter or from soils contaminated by heavy metals,and microorganisms capable of in situ extracellularly biosynthesis of metallic nanoparticles are obtained by enrichment,isolation and purification, when hydrochloroauric acid etc are used as substrates. The properties of the synthesized nanoparticles are analyzed by Uv-Vis,TEM,XRD,EDX and FTIR,and meanwhile,the presence of proteins and its functions in nano biosynthesis are analyzed by Uv-Vis,FTIR,SDS-PAGE.The bacteria is inoculated in the anode chamber of the microbial fuel cell,the extracellular electron transport pathway and the production of endogenous electrochemical mediators are analyzed by slow scan rate voltammetry and electrochemical impedance spectroscopy method. The endogenous electrochemical mediators are separated and purified by solid phase extraction and preparative liquid chromatography, and the molecular structure of the mediator are determined by the data from NMR,LC-MS,Uv-Vis and FTIR.The action mechanisms of the endogenous electrochemical mediators in the in situ extracellularly nano synthesis are reached by comparing and analyzing the results from the electrochemical properties of the bacteria, the presence of endogenous mediators, the extracellular nano synthesis performance of the bacteria and secreted proteins from the bacteria.

采集冶炼厂或重金属离子长期污染土样，分别以氯铂酸等金属离子为底物，富集、分离、纯化细胞外原位还原制备纳米粒子的细菌。采用Uv-Vis、TEM、XRD、EDX及FTIR等方法表征金属纳米粒子的性质，并同时采用Uv-Vis,FTIR,SDS-PAGE等方法分析细胞分泌的蛋白种类及在纳米生物合成中的作用。将选育得到的纳米粒子细胞外合成细菌接种于微生物燃料电池(MFC)阳极室，并通过慢扫速循环伏安及电化学交流阻抗等方法分析细菌的细胞外电子传递方式及内生电子媒介体的存在。利用固相萃取及制备型液相色谱分离内生电子媒介体，并根据NMR,LC-MS，UV-vis,FTIR结果鉴定内生电子媒介体的分子结构。将细菌的电化学性质、内生电子媒介体、细胞外纳米粒子合成特性以及细菌分泌的蛋白等因素进行综合分析，在此基础上推测内生电子媒介体在纳米粒子细胞外合成过程中的作用机制。

采集冶炼厂或重金属离子长期污染土样，分别以氯铂酸等金属离子为底物，富集、分离、纯化 细胞外原位还原制备纳米粒子的细菌。采用Uv-Vis、TEM、XRD、EDX及FTIR等方法表征金属纳 米粒子的性质，并同时采用Uv-Vis,FTIR,SDS-PAGE等方法分析细胞分泌的蛋白种类及在纳米生物合成中的作用。将选育得到的纳米粒子细胞外合成细菌接种于微生物燃料电池(MFC)阳极室，并通过慢扫速循环伏安及电化学交流阻抗等方法分析细菌的细胞外电子传递方式及内生电子媒介体的存在。利用固相萃取及制备型液相色谱分离内生电子媒介体，并根据NMR,LC-MS，UVvis,FTIR结果鉴定内生电子媒介体的分子结构。将细菌的电化学性质、内生电子媒介体、细胞外纳米粒子合成特性以及细菌分泌的蛋白等因素进行综合分析，在此基础上推测内生电子媒介体在纳米粒子细胞外合成过程中的作用机制.