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The introduction of various drugs onto commercial soft contact lenses (CLs) has emerged as a potentially effective strategy for treating microbial keratitis (MK) because drug-loaded CLs can maintain a controlled drug concentration which leaded to enhanced drug bioavailability and reduced side effects in ocular tissues. In this study, silver nanoparticles modified with zwitterionic poly (carboxybetaine-co-dopamine methacrylamide) copolymer (PCBDA@AgNPs) as novel anti-infective therapeutics were prepared and firmly immobilized onto soft CLs through mussel-inspired surface chemistry. The obtained PCBDA@AgNPs coated CL (PCBDA@AgNPs-CL) remained the excellent transparency of commercial CLs and exhibited strong and broad-spectrum antimicrobial activities. We systematically explored the mechanism and found that the functional CLs can effectively inhibit the growth of microbial biofilms via a synergic “resist–kill–remove” strategy due to the zwitterionic surface and sustained release of silver ions. Significantly, in vitro cell cytotoxicity and in vivo subcutaneous implantation experiments proved the significant biosafety of PCBDA@AgNPs-CL. Furthermore, PCBDA@AgNPs-CL was successfully employed for the in vivo treatment of MK rabbit models, demonstrating excellent abilities to eradicate microbe-induced ocular infections and to prevent the destruction and irreversible structural alterations of corneal tissues. Collectively, PCBDA@AgNPs-CL is therefore a highly promising therapeutic device to significantly boost the efficacy for MK treatment.

Inflammation and thrombosis are two major complications of blood-contacting catheters that were used as extracorporeal circuits for hemodialysis and life-support systems. In clinical applications, complications can lead to increased mortality and morbidity rates. In this work, a biomimetic erythrocyte membrane zwitterion coating based on poly(2-methacryloyloxyethyl phosphorylcholine-co-dopamine methacrylate) (pMPCDA) copolymers was uniformly and robustly modified onto a PVC catheter via mussel-inspired surface chemistry. The zwitterionic pMPCDA coating exhibited excellent antifouling activity and resisted bacterial adhesion, fibrinogen adsorption, and platelet adhesion/activation. The material also demonstrated great hemocompatibility, cytocompatibility, and anticoagulation properties in vitro. Additionally, this biocompatible pMPCDA coating reduced in vivo foreign-body reactions by mitigating inflammatory response and collagen capsule formation, due to its outstanding ability to resist nonspecific protein adsorption. More importantly, when compared with a bare PVC catheter, the pMPCDA coating exhibited outstanding anti-thrombotic properties when tested in an ex vivo rabbit perfusion model. Thus, we envision that this biomimetic erythrocyte membrane surface strategy will provide a promising way to mitigate inflammation and thrombosis caused by the use of blood-contacting catheters. This article is protected by copyright. All rights reserved.

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@AgNPs-CG 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.