Mechano‐Dynamic Analysis of the Bactericidal Activity of Bioinspired Moth‐Eye Nanopatterned Surfaces

In recent years, the understanding of the bactericidal mechanisms of natural surfaces has received great attention to unravel their design principles for the development of next-generation mechano-bactericidal surfaces. Due to the difficulty in characterizing the bacteria–nanostructure interface, many aspects of the physical interaction between bacteria and the surface, and the underlying bactericidal mechanisms, remain unclear. This study focuses on evaluating the dynamics of the mechano-bactericidal process in the case of the moth-eye bioinspired topography in relation to the bacteria strain and mechanical characteristics of the surface. The bacteria–nanostructure interface is examined by measuring the deformations inflicted by the nanotopography on the bacterial wall upon attachment using two techniques, namely atomic force microscopy and stereometric analysis of scanning electron microscopy images. All data match well and are in accordance with the expected bacteria mechanical deformation calculated by finite element modeling. This represents a practical methodology to measure bacterial deformations inflicted by nanotopography. The methodology can be implemented to any other bacteria strain or bactericidal topography to verify the degree of mechanical stress and bactericidal efficacy related to the topography and surface stiffness and may serve as a design basis for the fabrication of effective antibacterial surfaces.