Multifunctional chitosan-copper-gallic acid based antibacterial nanocomposite wound dressing.

Antibacterial wound dressings can effectively avoid the residual of antibacterial nanomaterials for injection in vivo , reduce their biological toxicity to normal cells and tissues, making them be widely applied in biomedical field. Herein, an approach of combining ion-crosslinking, in-situ reduction and microwave-assisted methods was employed to prepare chitosan-copper-gallic acid nanocomposites (CS-Cu-GA NCs) with dual-functional nano-enzyme characteristics (oxidase- and peroxidase-like functions). The oxidase-like activity of CS-Cu-GA NCs can facilitate the production of hydrogen peroxide (H 2 O 2) when it contacted with physiologically relevant antioxidants (AH 2) in bacteria. Subsequently, H 2 O 2 was catalyzed to generate hydroxyl radicals (OH) under the peroxidase-like activity of CS-Cu-GA NCs. Furthermore, CS-Cu-GA NCs integrate the inherent antibacterial properties of chitosan, Cu NPs and Cu2+. Animal experiments revealed that the antibacterial dressing incorporating CS-Cu-GA NCs exhibited its effective promotion of S. aureus -infected wounds healing, as well as no damage to normal tissues. Besides, the antibacterial dressing was prepared to a band aid with excellent water swelling and antibacterial properties, which was further fixed in a medical tape to construct a portable antibacterial product that can be applied to the surface of human skin and showed excellent waterproof performance, providing a new insight for the construction of clinical antibacterial wound healing products. Unlabelled Image • CS-Cu-GA NCs with oxidase-like and peroxidase-like functions were fabricated. • Oxidase- and peroxidase-like CS-Cu-GA NCs had strong antibacterial property. • CS-Cu-GA NCs combined the inherent antibacterial functions of CS, Cu NPs, Cu2+. • Biocompatible CS-Cu-GA NCs antibacterial dressing promoted wounds healing. • A portable multifunctional antibacterial product was constructed. [ABSTRACT FROM AUTHOR]