Sprayable Zwitterionic Antibacterial Hydrogel with High Mechanical Resilience and Robust Adhesion for Joint Wound Treatment.

Wound healing in movable parts, including joints and neck, remains a critical challenge due to frequent motions and poor flexibility of dressings, which may lead to mismatching of mechanical properties and poor fitting between dressings and wounds, thus increasing the risk of bacterial infection. Hence, this study proposed a sprayable zwitterionic antibacterial hydrogel with outstanding flexibility and desirable adhesion. This hydrogel precursor was fabricated by combining zwitterionic sulfobetaine methacrylate (SBMA) with poly(sulfobetaine methacrylate-co-dopamine methacrylamide)-modified silver nanoparticles (PSBDA@AgNPs) through robust electrostatic interactions. About 150 s of exposure to UV light, the SBMA monomer polymerized to form PSB chains entangled with PSBDA@AgNPs, which were transformed into a stable and adhesion PSB-PSB@Ag hydrogel at the wound site. The resulting hydrogel had adhesive strength (15-38 kPa), large tensile strain (>400%), suitable shape adaptation and excellent mechanical resilience. Moreover, the hydrogel displayed pH-responsive behavior, the acidic microenvironment at the infected wound sites prompted the hydrogel to rapidly release AgNPs and kill bacteria. Furthermore, the healing effect of the hydrogel was demonstrated on the rat neck skin wound, showing improved wound closing rate due to reduced inflammation and enhanced angiogenesis. Overall, the sprayable zwitterionic antibacterial hydrogel had significant potential to promote joint skin wound healing. This article is protected by copyright. All rights reserved.