Mussel-inspired immobilization of zwitterionic silver nanoparticles toward antibacterial cotton gauze for promoting wound healing

Silver nanoparticles (AgNPs) decorated medical cotton gauze (CG) is a promising antibacterial wound dressing designed to prevent bacterial infection and promote the wound healing. However, in clinical application, the silver loading stability of these AgNPs decorated CGs is currently still a challenge because the leaching of AgNPs from CG may not only cause gradual loss of antibacterial activity but also bring potential side effects. Herein, we developed zwitterionic AgNPs which were one-step synthesized by using poly (carboxybetaine-co-dopamine methacrylamide) copolymer (PCBDA) as a reducing and stabilizing agent under alkaline condition. Taking advantage of the mussel-inspired catechol/amino chemistry, the zwitterionic PCBDA@AgNPs can be facilely and robustly immobilized onto amino-modified CG via both covalent and noncovalent interactions. Owing to the zwitterionic interface of immobilized AgNPs and the sustained release of Ag+, the as-prepared PCBDA@AgNPsCG not only exhibited excellent bacterial antiadhesive and bactericidal activity but also inhibited biofilm formation in vitro. In addition, this PCBDA@AgNPs-CG possessed good hemocompatibility and cytocompatibility, which is beneficial to be wound dressing. More importantly, in vivo wound healing assay confirmed that this PCBDA@AgNPs-CG dressing could effectively inhibit the wound infection, reduce the inflammatory response and hence promote wound healing. Therefore, such PCBDA@AgNPs-CG dressing has great potential for use in infectious wound management.