Photocatalytic Antibacterial Capabilities of TiO 2 −Biocidal Polymer Nanocomposites Synthesized by a Surface-Initiated Photopolymerization

Novel biocidal polymer-functionalized TiO(2) nanoparticles were prepared by surface-initiated photopolymerization using titania as an initiator. Vinyl monomer mixtures of nontoxic secondary amine-containing biocidal 2-(tert-butylamino)ethyl methacrylate and antifouling ethylene glycol dimethacrylate were used for the antimicrobial polymer shell. It was shown that the synthesized TiO(2)/poly[2-(tert-butylamino)ethyl methacrylate-co-ethylene glycol dimethacrylate] core/shell nanoparticles had enhanced photocatalytic antibacterial properties compared to the pristine TiO(2) nanoparticles due to the combined antibacterial activities of light-driven anti-infective TiO(2) core and biocidal polymer shell. In the dark condition, the TiO(2)/biocidal polymer nanoparticles exhibited high antimicrobial efficiency (95.7%) against gram-positive S. aureus. Furthermore, during UV irradiation, the TiO(2)/biocidal polymer showed improved inhibition of bacterial growth against gram-negative E. coli and gram-positive S. aureus in comparison to the pristine TiO(2) nanoparticles.