Antibacterial and bactericidal properties of resin nanostructures coated with SiO₂ thin films

Nanotextures exhibit physical antibacterial and bactericidal properties; hence, they have great potential to prevent infection related to bacteria through contact. The surface characteristics of a nanostructure determine its antibacterial and bactericidal activities. In this study, an atomic layer deposition (ALD) was used to prepare nano-level, hard, thin SiO₂ layers on resin nanostructures and their effects were demonstrated through antibacterial and bactericidal tests. The SiO₂-layer-coated resin nanostructure exhibited a water contact angle of 7.2°, dramatically lower than that of the uncoated specimen (130.2°), as well as a three-fold higher local elastic modulus. Further, 10-nm-thin SiO₂-layer-coated nanopillars showed antibacterial and bactericidal effects against E. coli. These results demonstrate that SiO₂ thin layer coating has great potential for improving the antibacterial and bactericidal properties of polymeric nanopillar arrays.