Mesoporous silica loaded with peracetic acid and silver nanoparticles as a dual-effect, highly efficient bactericidal agent

Mesoporous silica (SBA-15) with peracetic acid (PAA) adsorbed on its mesopores together with silver nanoparticles attached to their pore walls show a strong bactericidal effect on antibiotic-resistant and biofilm forming Staphylococcus aureus, considerably larger than that expected from the summation of the independent effects of both antimicrobials. Ag nanoparticles were formed in situ, by loading silver nitrate in the pores of the amino-functionalized mesoporous silica, followed by the addition of a reducing agent. The size of the silver nanoparticles could be tuned depending on the amount of silver precursor. The ordered mesoporous structure of SBA-15 is preserved after the formation of Ag nanoparticles and subsequent PM loading which allows for the sustained release of both agents. Therefore, in this work, a long-term antimicrobial releasing nanostructured carrier with a synergistic bactericidal action is presented. (C) 2012 Elsevier Inc. All rights reserved.