Abstract
In this thesis, we report a novel method using Deinococcus radiodurans IR culture to fabricate silver nanostructures, including nanoparticles and nanowires, and discuss the hypothetical mechanism of their formation. After series of experiments, we found that these black wires and particles only exist in stationary phase cultures. These black wires are metallic silver after being analyzed by energy dispersive X-ray spectrometer, and the size of them is from 60 to 100 nm in width. Furthermore, as we immobilize cells on wafer surface, silver nanowires also exist and connect at least one cell. Even more, there are silver nanowire network connecting several cells, too. Straight and curved silver nanowires are observed and the curvature is formed through influence of certain effecter cells beside the wire. We also tested some heavy metal ions, such as gold (III) and copper (II), to know what the relationship between cell aggregates formation and reduction potential is and to see if same condition can be applied to other metal ions. In conclusion, we believe that D. radiodurans IR culture could be a very efficient system to fabricate silver nanostructures and silver nanowire networks.