Ag NP catalysis of Cu ions in the preparation of AgCu NPs and the mechanism of their enhanced antibacterial efficacy

Aqueous dispersions of AgCu nanoparticles (NPs), with enhanced antibacterial efficacy, have been prepared through the catalyzed reduction of Cu ions by PVP/PVA-stabilized Ag nanoparticles at 85 °C. The effects of Cu concentration and heating time on NP morphology and antibacterial efficacy were investigated, using TEM, UV-Vis and FTIR spectroscopies, and antibacterial evaluations. The enhanced antibacterial performance of these NPs was correlated with Ag ion release. We propose a simple model of AgCu NP formation, and an enhanced antibacterial efficacy mechanism involving Ag ion release, in which AgCu NPs formation plays a role to control of Ag ion release.