Nanostructured antibacterial surfaces have recently gained significant interest for their ability to mechanically disrupt bacterial cells and reduce populations. This study presents an efficient method for fabricating PMMA nanostructures using Electron Beam Lithography, focusing on nanograting and nanopillar arrays with pitches ranging from 160 to 200 nm. Atomic Force Microscopy was employed to characterize these structures. The antibacterial efficacy was assessed against Escherichia coli revealing a significant reduction in bacterial adhesion, grown on the nanostructures compared to the flat PMMA surfaces, with the nanopillars showing a more pronounced effect (about 85 %) compared to the nanogratings (75 %). The bacteria exhibited significant shape changes and damage, indicative of severe cellular disruption. Detailed AFM analysis confirmed notable morphological changes, including reduced major axis …