Superhydrophobic Coatings for Urinary Catheters to Delay Bacterial Biofilm Formation and Catheter-Associated Urinary Tract Infection

In this research, a multilayered superhydrophobic coating for urinary catheters was synthesized by a layer-by-layer deposition technique. A mussel-inspired polydopamine coating was utilized as a platform for the in situ anchoring of silver nanoparticles followed by hydrophobic modification with 1H,1H,2H,2H-perfluorodecanethiol. Benefiting from the synergistic effect of hierarchical micro/nanostructures and antibacterial silver nanoparticles, the prepared catheters exhibited excellent superhydrophobicity and prolonged antibacterial activity against Escherichia coli WT F1693 and Proteus mirabilis WT F1697. Compared with commercial all-silicone and silver-alloy-hydrogel catheters, the superhydrophobic catheter exhibited significant antibiofilm activities in both static and dynamic models. In an in vitro bladder model, bacterial migration along the outer catheter was effectively delayed, reducing biomass accumulation by up to 55 and 90% compared with all-silicone and silver-alloy-hydrogel catheters. Encrustations in the catheter lumen were also retarded, extending the lifetime of silicone catheters from ∼40 to ∼100 h. The superhydrophobic catheter also exhibited good biocompatibility to the L929 mouse fibroblasts, therefore providing a promising direction for the future design of urinary catheters.