Silver, dispersion

Our silver nanoparticles (40 nm in diameter) are spherical nanoparticles of metallic silver dispersed in an aqueous citrate buffer. This buffer stabilizes the dispersion; citrate ions adsorb onto the surface of the silver nanoparticles and create a protective layer that prevents aggregation. Because of the nanoparticles′ small size the nanoparticles exhibit quantum confined optical properties, most notably an emission wavelength of (λem) of412 nm with a full width at half maximum (FWHM) of only 63 nm, owing to the monodispersity of the particles. The optoelectronic properties in combination with a high surface area make our silver nanoparticles useful in biosensors and fluorescent imaging for the sensitive detection of biomolecules, pathogens, and environmental contaminants.