Lubricating Copolymer Brushes Achieving Excellent Antiadhesion and Antibacterial Performance through Hydration and Electrostatic Repulsion Effects

Interventional catheters have been widely applied in diagnostics, therapeutics, and other biomedical areas. The complications caused by catheter-related bacterial infection, venous thrombosis, and vascular abrasion have become the main reasons for the failure of interventional therapy. In this study, polyacrylamide/poly(acrylic acid) lubricating copolymer brushes were constructed on the surface of catheters and efficiently resisted the adhesion of blood components and bacteria through hydration and electrostatic repulsion effects. The copolymer brushes are surface-independently constructed on various substrates through a three-step method. The brushes achieve effective lubricating, antiadhesion, and antibacterial properties. Particularly, the 2PAM/6PAA brushes exhibited the most excellent overall performance with a 94% reduction in coefficient of friction, 87.2 and 78.3% reduction in adhesion levels of bovine serum albumin and bovine blood fibrin, and 92.3, 97.1, and 93.5% reduction in adhesion levels of Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. The 2PAM/6PAA brushes significantly reduced the adhesion of blood components in the in vitro blood circulation test, demonstrating its practical application efficacy. Additionally, experiments and molecular dynamics simulations were used to reveal the antiadhesion mechanism of the brushes. Thus, the copolymer brushes in this work show great potential in the antithrombotic, antibacterial, and lubrication modification for medical devices contacting with blood.