Antibacterial Conductive Collagen-Based Hydrogels for Accelerated Full-Thickness Wound Healing

Antibacterial conductive hydrogels have been extensively utilized in tissue repair and regeneration on account of their unique electrochemical performances and advantages of anti-pathogenic bacterial infection. Here, multi-functional collagen-based hydrogels (CHLY) with adhesivity, conductivity, and antibacterial and antioxidant activities were developed by introducing cysteine-modified ε-poly(l-lysine) (ε-PL-SH) and in situ-polymerized polypyrrole (PPy) nanoparticles to induce full-thickness wound healing. CHLY hydrogels have a low swelling ratio, good compressive strength, and viscoelasticity due to chemical crosslinking, chelation, physical interaction, and nano-reinforcements in the matrix network of hydrogels. CHLY hydrogels possess excellent tissue adhesion ability, low cytotoxicity, enhanced cell migration ability, and good blood coagulation performance without causing hemolysis. Interestingly, the chemical conjugation of ε-PL-SH in the hydrogel matrix gives hydrogels an inherently robust and broad-spectrum antibacterial activity, while the introduction of PPy endows hydrogels with superior free radical scavenging capacity and good electroactivity. Significantly, CHLY hydrogels have advantages in alleviating persistent inflammatory response as well as promoting angiogenesis, epidermis regeneration, and orderly collagen deposition at the wound sites through their multi-functional synergies, thus effectively accelerating full-thickness wound healing and improving wound healing quality. Overall, our developed multi-functional collagen-based hydrogel dressing demonstrates promising application prospects in the field of tissue engineering to induce skin regeneration.