Bactericidal Performance of Nanostructures Resin Surfaces: Nanopillars versus Nanocones

Recent attention has been directed toward understanding the antibacterial mechanisms of artificial nanostructured surfaces, aiming to elucidate design principles for next-generation mechanobactericidal surfaces. This study assesses the mechanobactericidal performance of bacteria cell membrane strain and the mechanical characteristics of resin nanostructures. Five nanopatterns with pitch, diameter, height, and shape variations were fabricated by using thermal nanoimprint techniques. We analyzed their shape via scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, this study correlated the live/dead ratios of E. coli cells confirmed using fluorescence microscopy with the local elasticity modulus (LEM) measured by AFM or the bending deformation of the nanostructures calculated by finite element simulation in a comparative experiment. Notably, nanopillar structures exhibited superior bactericidal properties compared to those of nanocone structures. In addition, the nanotopology optimization of the surface can better control the nanostructured LEM, thereby affecting the bactericidal properties of E. coli cells.