(293b) Preventing Bacterial Biofilm Formation Using Active Surface Topography

¹Department of Biomedical and Chemical Engineering, ²Syracuse Biomaterials Institute, ³Department of Civil and Environmental Engineering, ⁴Department of Biology, Syracuse University, Syracuse, NY 13244, United States

Bacterial adhesion on biotic or abiotic surfaces and the subsequent formation of multicellular biofilms cause persistent biofouling in industrial settings and drug-resistant infections in humans. Biofilm-associated challenges have stimulated extensive research to develop effective strategies for biofilm prevention and removal. However, most of the technologies to date are based on static features and thus are only effective for short-term control. To address this challenge, we developed a new method to repel bacteria with actively moving topographic structures, made with micron-scale poly(dimethylsiloxane) (PDMS) pillars with superparamagnetic Fe₃O₄ nanoparticles secured at the tip of each pillar. The movement of pillars was controlled by a programmable external electromagnetic field. The antifouling effects of cylindrical-shaped pillars with a diameter of 2 µm, height of 10 µm, and stiffness (Young’s modulus) of 2.61 MPa, was optimized by varying the inter-pattern distance as 2, 5, 10, 15 or 20 µm. The inter-pattern distance of 5 µm exhibited the best activity in the prevention and removal of Pseudomonas aeruginosa PAO1 biofilms. The continuous movement of such topographic features for 6 h showed 95.3 ± 0.7 % reduction of P. aeruginosa PAO1 biofilm formation compared to static pillars. On-demand actuation of these pillars for 3 min detached mature (48 h) P. aeruginosa PAO1 biofilms by 99.9 ± 0.1%. With the capability to prevent bacterial adhesion and remove mature biofilms, this technology has potential applications in engineering smart medical devices, e.g., antifouling catheters.