Controlling biofilm formation with nitroxide functional surfaces

Bacterial biofilm formation on medical devices is a threat to healthcare systems worldwide as bacteria within a biofilm are more resistant to standard antimicrobial therapies. Herein, we introduce a nitroxide-based antibiofilm coating strategy, which is specifically designed to prevent biofilm formation of Gram-negative pathogens such as Pseudomonas aeruginosa. Nitroxide-decorated hydroxyapatite surfaces were readily prepared in an aqueous dip-coating procedure using a nitroxide-functionalized catecholamine as a polymerizable coating agent. Additional spatial control over the polymer surface deposition on titanium was gained by applying a photolithographic coating setup. All nitroxide-coated surfaces exhibited excellent antibiofilm properties toward PA14 surface colonization as biofilm formation was completely suppressed. Importantly, the surrounding adhesive polymer matrix did not interfere with the nitroxide-characteristic antibiofilm properties. The herein introduced platform technology represents a bioinspired and versatile coating approach, offering a safe and prophylactic avenue to combat biofilm contamination on a variety of surfaces.