Structure-Dependent Biological Response of Noble Metals: From Nanoparticles, Through Nanowires to Nanolayers

Abstract

Noble metals in their diverse nanoforms bring revolution to many fields of science and technology, as they provide unique properties over their bulk counterparts. Thanks to these completely unprecedented properties, commercial sphere pressure is growing to use them in everyday life. Unfortunately, one of the issues that are subject to dramatic changes is the reactivity of these structures. This may have often fatal consequences to the living organisms. Due to the fact that the mechanism of action of metal nanostructures on living organisms is not yet fully elucidated even in the case of the most studied noble metals such as gold and silver, it is necessary to continue intensively in their research, characterization and categorization. The main prerequisite for the undistorted study of interactions of nanostructures with living organisms is the use of suitable methods of their preparation. Within this context, this chapter attempts to summarize current knowledge form the field of synthesis of metal nanoparticles, layers, wires, and other nanostructures, especially regarding novel techniques of their preparation and extend them by our own results in this area, in the context of their biological properties. More specifically, antibacterial efficacy and potential cytotoxicity of those structures are thoroughly addressed.

Combined Structural and Plasmonic Enhancement of Nanometer-Thin Film Photocatalysis for Solar-Driven Wastewater Treatment

“…Our approach avoids nanostructuring of noble metals, which is typically achieved by complex and time-consuming wet chemical processing . Furthermore, similar to TiO 2 nanoparticles, the impact of such metal nanoparticles on living organisms and the environment remains unclear. − We circumvent these issues by incorporating the nanostructures in a glass (SiO 2 ) substrate and then creating different material stacks with high surface areas on top of it. We demonstrate the efficiency of our photocatalytic devices through the reduction of methylene blue (MB) dye under different illumination wavelengths.…”