Enhanced antibacterial activity of polyphenol-bound microtopography by synergistic chemical and micro/nanomechanical effects

Initial microbial attachment on surfaces is the first step in bacteria contamination and direct intervention in the early adhesion stage by constructing an antibacterial coating is an effective strategy to prevent the attachment and proliferation of bacteria. Herein, a storable polyphenol-based coating is designed and fabricated by self-assembling the cationic template and ionic ligand. The materials containing microparticles with sticky properties inherited from tannic can be deposited on various surfaces by a simple redispersion-immersion process. The functional ligands on the outer layer of the coating can kill bacteria by combining chemical damages produced by tannic as well as mechanical disruption caused by the micro-nano topography as reflected by the elevated Young's modulus and differentiated stiffness of the bacterial membrane. The results reveal a simple method to prepare polyphenol-based antibacterial coatings and enrich our understanding of the combined use of chemical and mechanical interventions to enhance the antibacterial activity. © 2024 Elsevier Ltd