The preparation of highly active antimicrobial silver nanoparticles by an organometallic approach.

Silver nanoparticles of small size with a high surface to volume ratio have been prepared using an organometallic approach. For this, the complex NBu(4)[Ag(C(6)F(5))(2)] has been treated with AgClO(4) in a 1:1 molar ratio, giving rise to the nanoparticle precursor [Ag(C(6)F(5))] in solution. Addition of one equivalent of hexadecylamine (HDA) and 5 h of reflux in toluene leads to a deep yellow solution containing monodisperse silver nanoparticles (Ag NPs) of ca. 10 nm. This approach leads to nanoparticles with almost uncontaminated surfaces which make them very reactive. Antimicrobial studies show that these nanoparticles are very active as antimicrobial agents. Very low concentrations between 12 and 25 µg ml(-1) of Ag NPs are enough to produce bacteriostatic and bactericidal effectiveness.