Design of Near-Infrared-Triggered Cellulose Nanocrystal-Based Intelligent Wound Dressings for Drug-Resistant Bacteria-Infected Wound Healing.

Postoperative infected wound complications caused by residual tumor cells, bacterial biofilms, and drug-resistant bacteria have become the main challenge in postsurgical skin regeneration. Herein, a bionic cellulose nanocrystal (CNC)-based intelligent wound dressing with near-infrared (NIR)-, temperature-, and pH-responsive functions was designed by using NIR-responsive CNC as the network skeleton, dynamic imine bonds between dialdehyde cellulose nanocrystals and doxorubicin, chitosan oligosaccharide as the pH-responsive switch, and temperature-sensitive poly(-isopropyl acrylamide) as the temperature-responsive formation switch. The as-prepared wound dressing with the intertwining three-dimensional (3D) network structure possessed high drug loadability of indocyanine green (30 mg/g) and doxorubicin (420 mg/g) simultaneously. The temperature-, NIR-, and pH-responsive switches endowed the wound dressing with controllable on-demand drug release behavior. In particular, the temperature switch endowed the dressing with a shape-adaptable ability on irregularly infected wounds. Interestingly, the wound dressing showed excellent antitumor activity for A375 tumor cells, antibacterial activity against methicillin-resistant (MRSA) and bacterial biofilm removal ability. Therefore, the developed wound dressing can provide an ideal synergistic treatment strategy combined with chemotherapy and photodynamic and photothermal therapy for postoperative drug-resistant bacteria-infected wound healing.