Nanozyme-Based Stretchable Hydrogel of Low Hysteresis with Antibacterial and Antioxidant Dual Functions for Closely Fitting and Wound Healing in Movable Parts

y Wound healing in movable parts including joints and neck remains a critical challenge due to frequent motions and poor flexibility of dressing which may lead to mismatching of mechanical properties and poor fitting between dressings and wounds, thus increasing the risk of bacterial infection and inflammation. Herein, through the copolymerization of N-isopropylacrylamide, acrylamide, and acryloyl Pluronic 127 (PF127-DA), and functionalization by molybdenum disulfide-polydopamine nanozyme (MP), a new type of stretchable, adhesive, and low hysteretic MP composite hydrogel (MPH) with antibacterial and antioxidant dual functions for closely fitting and wound healing in movable parts is designed. The excellent mechanical properties (stretching about 616%, hysteresis about 0.17) and adhesiveness (about 3.25 kPa) of MPH make it fast to match the motions of the movable parts, close to fit with wound resisting bacterial invasion, and effective to avoid secondary dressing fixation. Furthermore, the dual functions of antibacterial derived from photothermal properties and antioxidant derived from intrinsic enzyme-like activity can eliminate the infection (exposing to 808 nm irradiation, the killing ratios for Staphylococcus aureus and Escherichia coli are 99.1% and 93.9%), reduce oxidative stress, improve wound microenvironment, and promote wound healing.

Automated summary

The newly designed MP composite hydrogel exhibits excellent mechanical properties and adhesiveness, providing a close fit for movable parts and effectively preventing bacterial infection, ultimately promoting wound healing.