High-strength, fatigue-resistant, and fast self-healing antibacterial nanocomposite hydrogels for wound healing

The development of functional medical dressings with mechanical designability for complex wounds is crucial for the repair of tissue function. As one of the promising strategies in treating complex wounds, the unsatisfying mechanical properties and low-efficiency antimicrobial biofilm for liquid or gel dressings greatly limit their applications in many emergencies. Therefore, it is highly desirable to construct hydrogel dressings with high fatigue resistance, self-healing, and antibacterial biofilm properties. Here, we reported a strategy to build a nanocomposite hydrogel dressing to overcome these problems. The hydrogel dressings incorporated gold nanorods and Ca2+ into polyacrylic acid and polyvinyl alcohol, which endorsed the double network structure with good toughness (-551 KJ/m3), and excellent fatigue resistance (efficiency -82.4 %). In addition, the hydrogel dressings have good biocompatibility. Significantly, the gold nanorods incorporated in the hydrogel network provide a practical photothermal effect to initiate the self-healing function (self-healing efficiency -88.2 %) and effectively eliminate various multi-bacterial biofilm (-80 %). Furthermore, we showed that the hydrogel dressing could remove the wound bacterial biofilm and promote infected wound healing in vivo.

Automated summary

The development of functional medical dressings with mechanical designability is essential for tissue repair. However, existing liquid or gel dressings have limitations in terms of mechanical properties and antimicrobial biofilm, hindering their applications in emergency cases. In this study, a nanocomposite hydrogel dressing was developed, incorporating gold nanorods and Ca2+ into polyacrylic acid and polyvinyl alcohol, resulting in a double network structure with high toughness and excellent fatigue resistance. The hydrogel dressings exhibited good biocompatibility, self-healing function, and efficient elimination of bacterial biofilm. Moreover, the dressing was found to promote wound healing in vivo.