The multi-faceted mechano-bactericidal mechanism of nanostructured surfaces
Elena P. Ivanova, Denver P. Linklater, Marco Werner, Vladimir A. Baulin, XiuMei Xu, Nandi Vrancken, Sergey Rubanov, Eric Hanssen, Jason V. Wandiyanto, Vi Khanh Truong, Aaron Elbourne, Shane Maclaughlin, Saulius Juodkazis, Russell J. Crawford
Abstract
bacteria, inducing 95 ± 5% and 83 ± 12% cell death, respectively. At heights of 360 nm, increased nanopillar elasticity contributes to the onset of pillar deformation in response to bacterial adhesion to the surface. Theoretical analyses of pillar elasticity confirm that deflection, deformation force, and mechanical energies are more significant for the substrata possessing more flexible pillars. Increased storage and release of mechanical energy may explain the enhanced bactericidal action of these nanopillar arrays toward bacterial cells contacting the surface; however, with further increase of nanopillar height (420 nm), the forces (and tensions) can be partially compensated by irreversible interpillar adhesion that reduces their bactericidal effect. These findings can be used to inform the design of next-generation mechano-responsive surfaces with tuneable bactericidal characteristics for antimicrobial surface technologies.