A facile method to construct hybrid multilayered films as a strong and multifunctional antibacterial coating

A multifunctional multilayered film containing TiO2 nanoparticles as contact-active antibacterial agent and nanosilver as a release-active antibacterial agent was fabricated via layer-by-layer assembly. TiO2 nanoparticles with the anatase crystalline dominant structure were synthesized via a sol-gel method. The QCM, AFM, and contact angle measurement results indicated that the TiO2 nanoparticle-chitosan was successfully assembled with heparin via layer-by-layer assembly. The UV visible spectroscopy demonstrated that the silver ions could be loaded into the multilayers and in situ synthesize silver nanoparticles in the multilayers template. The short-term antibacterial assay showed the TiO2-chitosan/heparin multilayers loaded with nanosilver was bactericidal both in the low intensity UV light and in the dark. The long-term antibacterial assay indicated although the antibacterial in dark decreased with the PBS immersion time, the hybrid multilayered films sustained the long-term antibacterial in the low intensity UV light. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008