Core-Shell Structure-Based Smart Hydrogel Wound Dressing with Endogenous and Exogenous Dual Adhesion Dynamic Response to Promote Wound Healing

Herein, MIL-88b-NH 2 nanocage is designed with adenine inside the cage and tannins as gating outside the cage. Based on this core-shell structure, polyvinyl alcohol/carboxymethyl chitosan/MIL/adenine/tannic acid (PCMAT) hydrogels are able to respond endogenously and exogenously at different stages of wound healing. The engineered hydrogel is designed to have tunable adhesion and intelligence. The optimal PCMAT-0.3 hydrogel reduced the pore size to ≈13.5 µm under endogenous response conditions, and the antimicrobial performance reached more than 80% within 6 h. Tensile strength and strain at break are reduced by 8.47% and 60.52% respectively under exogenous response conditions. Evaluation of the healing effect on mouse back wound tissue shows that the wound healing rate is significantly better than the control group without nanocage incorporation on day 14. It provides an idea for the development of smart response hydrogel wound dressing that integrates multifunctionality.