Extracellular matrix-inspired natural-based composite hydrogel dressings for infected wound healing

Abstract

Developing an effective hydrogel dressing against bacterial infection and synchronously integrating mechanical robustness and the self-healing property is highly desirable for infected wound healing in clinical practice. Inspired by extracellular matrix (ECM), we constructed the dynamic and nondynamic synergy network to prepare the natural-based composite hydrogel dressing serving for infected wounds. The aldehyde groups of oxided hyaluronic acid was bonded with amino groups of carboxymethyl chitosan and polyacrylamide (PAAm) via the Schiff base reaction to form the dynamic crosslinked network, mimicking the dynamically reversible glycosaminoglycan network in the ECM. The nondynamic PAAm network was further created by UV-irradiated free radical polymerization, analogous to the covalently crosslinked collagen network in the ECM. The elaborate dynamic and nondynamic synergy network enabled the resultant hydrogel dressing to exhibit high mechanical strength and fatigue resistance , the excellent self-healing property and remarkable antibacterial activity. An in vivo staphylococcus aureus-infected full-thickness wound model revealed that our natural-based composite hydrogel dressing significantly reduced inflammation, promoted the formation of granulation tissue and angiogenesis to achieve the accelerated infected wound healing. This work offers a valuable reference to design and fabricate multifunctional hydrogel dressings for treating wound infection.