INOR 263 |
| While gold and silver are inert in their bulk form, size reduction to the nanoscale is known to lead to immense applications that range from catalysis and photonics to biological applications like diagnosis, drug delivery, and cancer imaging and therapy. Common methods to prepare stable nanoparticles (NPs) are based on chemical or electrochemical reduction. We describe the development of stable Au, Ag and mixed Au/Ag NPs that are soluble both in aqueous and organic media. The method described here is mild and undemanding with simple Au(I) and Ag(I) mononuclear or ionic precursors being reduced to Au and Ag NPs upon photolysis. Different template systems of either polymer microgels of poly(N-isopropylacrylamide-co-acrylic acid) (i.e., PNIPAM-aa) or the biopolymer Chitosan act as stabilizing agents and have been employed in absence of common reducing agents. These templates compared to the ones reported in the literature provide some advantages as microgels undergo large volume phase transitions in response to small change in physical and chemical environments. The spectral properties of the various NPs have been characterized by electronic absorption, luminescence, and Raman spectroscopies, while their shape and size have been characterized using HRTEM and DLS. |
|
Nanoscience: Applications
7:00 PM-10:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Inorganic Chemistry |