Enhanced Stability of Poly(3-sulfopropyl methacrylate potassium) Brushes Coated on Artificial Implants in Combatting Bacterial Infections

During the process of transplant operation, pathogens can inevitably come in contact with the implants to cause bacterial infections. Biofilms can then form on the implants, which can enhance the chance of inducing peri-implantitis to result in the failure of implantation. Grafting of anti-biofouling polymer brushes on the implants is a promising method to prevent the above issues. However, degrafting problems of polymer brushes might inhibit durable applications. Herein, we present the fabrication of poly(3-sulfopropyl methacrylate potassium) (PSPMAK) brushes on silicon substrates through multiple single bonds, abbreviated as (M-PSPMAK). These brushes display an enhanced stability, and can remain attached in aqueosus solutions for at least 32 days with less than 10% chain degrafting. The brush-coated surfaces exhibit excellent anti-biofouling behavior against bacteria, while mammalian cells can attach on the surface freely to promote implant interaction with healthy tissues. The stable brushes can also effectively inhibit the formation of a bacterial biofilm. As a proof of principle, we mimicked the implantation process by implanting M-PSPMAK brushes coated silicon in rats. The animal experiments indicate that the brush displays a good anti-biofouling behavior by resisting bacterial attachment. The above results indicate that M-PSPMAK brushes with enhanced stability have great potential to be applied as long-term anti-biofouling coating on artificial implants to reduce the chance of bacterial infection in clinic.