Mechanism of Silver Nanoparticles as a Disinfectant

ABSTRACT Using environmentally friendly synthesis techniques, monodispersive silver nanoparticles (AgNPs) were engineered. These particles exhibited bactericidal activity against Escherichia coli under both light and dark conditions. Unlike sodium hypochlorite, which demonstrated almost immediate disinfection, AgNPs required 30 min. In contrast to hypochlorite, however, the minimum dose of AgNPs decreased as the incubation time increased to less than 1 part per million. The mechanism whereby the nanoparticles inactivate the microbe is speculated to incorporate three distinct pathways. Collectively, the advantages of using AgNPs are (1) long-term efficacy; (2) effectiveness at ultralow doses; and (3) generation of little or no waste during the synthesis.