Design of Thermoplastic Polyurethanes with Conferred Antibacterial, Mechanical, and Cytotoxic Properties for Catheter Application.

Thermoplastic polyurethanes () are proposed as suitable solution for the fabrication of biocompatible catheters with appropriate mechanical parameters and confirmed antibacterial and cytocompatible properties. For this purpose, a series of quaternary ammonium salts () and quaternary phosphonium salts () based monomers were prepared followed by the determination of their minimal inhibitory concentrations (MICs) against Gram-positive () and Gram-negative (). A combination of the most active ammonium () and phosphonium () salts led to a MIC down to 2.4 μg/mL against and 9 μg/mL against , corroborating the existence of a synergistic effect. These quaternary onium salt () units were successfully incorporated along the polymer chain, as part of a two-step synthesis approach. The resulting materials were subsequently characterized through thermal, mechanical, and surface analyses. (combining the most active and units) showed the highest antibacterial efficiency, confirming the synergistic effect between both groups. Finally, an MTT assay on the SiHa cell line revealed the low cytotoxicity level of these polymeric films, making these materials suitable for biomedical application. To go one step further in the preindustrialization approach, proof of concept regarding the catheter prototype fabrication based on / was validated by extrusion.