| Metal nanoparticles and nanoshells based on gold, silver, and palladium exhibit unique optical properties due to the collective oscillation of conducting electrons near their surfaces, which is referred to as the surface plasmon resonance. Silver cores coated with gold shells and silica cores coated with gold, silver, gold-silver alloy, palladium, gold-palladium alloy shells, and silver nanorods were reliably prepared. These nanoparticles were completely characterized by DLS, FE-SEM, EDX, UV-vis, TEM, XRD, FT-IR, and XPS. The data demonstrate the formation of these metal nanoparticles whose optical properties were tunable over the wavelength range of 300 to 1500 nm depending on their compositions and structures. This unique tunability makes these metal nanoparticles ideal candidates for catalytic, optical, and electrical devices. Moreover, gold nanoparticles and gold nanoshells were further incorporated with biocompatible hydrogel polymers that respond rapidly to changes in temperature slightly above that found in the human body. These hybrid nanoparticles can thus be used as a drug-delivery system that can be specifically targeted and optically activated. |
