Abstract: 

The formation of biofilm and thrombus on medical catheters poses a significant life-threatening concern. Hydrophilic anti-biofouling coatings upon catheter surfaces with complex shapes and narrow lumen have demonstrated to be potential in reducing complications. However, their effectiveness is constrained by the poor mechanical stability and weak substrate adhesion. Herein, a novel zwitterionic polyurethanes (SUPU) with strong mechanical stablity and long-term anti-biofouling was developed by controlling the ratio of sulfobetaine-diol (SB-diol) and ureido-pyrimidinone (UPy). Once immersion in water, as-synthesized zwitterionic coating (SUPU3 SE) would undergo a water-driven segment reorientation to obtain a much higher durability than its direct drying one even under various extreme treatments, including acidic solution, abrasion, ultrasonication, flushing and shearing in PBS at 37 ℃ for 14 days. Moreover, SUPU3 SE coating could achieve a 97.1% of exceptional reducing protein fouling, complete prevention of cell adhesion and a long-lasting anti-biofilm performance even after 30 days. Finally, the good anti-thrombogenic formations of SUPU3 SE coating with bacterial treatment were validated in blood circulation through an ex-vivo rabbit arteriovenous shunt model. This work provides a facile approach to fabricate stable hydrophilic coatings through simple solvent exchange to reduce thrombosis and infection of biomedical catheter.