Antibacterial Collagen-Based Nanocomposite Dressings for Promoting Infected Wound Healing

Pathogenic bacterial infection is the most frequent wound complication, which has become a major clinical and healthcare challenge in wound management worldwide, leading to impaired healing processes, the risk of amputation, and even death. Here, collagen-based nanocomposite dressings (APZC) with broad-spectrum antibacterial activity are developed to promote the infected full-thickness wound healing. Short rod-like shaped ZnO NPs are synthesized and then coated with polydopamine (PDA) to obtain PDA coated ZnO NPs (PDA@ZnO NPs). Afterward, PDA@ZnO NPs are conjugated on the backbone of a collagen chain, and the obtained collagen-PDA@ZnO NPs conjugate is crosslinked by dialdehyde sodium alginate to fabricate APZC dressings. PDA@ZnO NPs show well dispersibility and are uniformly incorporated into the collagen matrix. APZC dressings have interconnected microporous structure and great physicochemical properties, besides good blood coagulation performance and well cytocompatibility. APZC dressings demonstrate long-lasting and excellently broad-spectrum antimicrobial activity, which can relieve the inflammatory reaction by killing pathogenic bacteria and induce the generation of blood vessels and the orderly deposition of collagen in the wound site, thus promoting infected full-thickness wound healing without obvious scar formation. Overall, the functionalized collagen-based nanocomposite dressings have great potential in the clinical treatment against bacteria-associated wound infection.