Multifunctional Dynamic Enamine‐Based Hydrogels with On‐Demand Removability for Wound Healing

Abstract To meet the urgent requirement in complex wound treatment, the injectable self‐healing biocompatible hydrogel with tunable mechanical properties, adhesion, on‐demanding removability, antibacterial properties, and hemostasis is designed. For the first time, hydrogels are fabricated through dynamic enamine bonds among dodecane grafted quaternized chitosan (DQCS) and ketone group functionalized polyvinyl alcohol (PVA‐Ket) to achieve efficient wound closure. Owing to the dynamic enamine bond, the hydrogel exhibits self‐healing, injectability and suitable mechanical properties. It can be easily injected into wound, adhere tightly, and bear deformation damage. Dodecyl groups and quaternary amine groups endow the biocompatible hydrogels outstanding antibacterial feature, hemostatic performance, and tissue adhesiveness (40.05 ± 3.21 kPa), which greatly facilitate the wound healing process. Owing to interaction between the amino acid and PVA‐Ket, the hydrogel exhibits painless on‐demand dissolution behavior, causing uninjurious separation from wound sites. Furthermore, in vivo study demonstrates that the hydrogel promotes wound healing by upregulating growth factors, alleviating the inflammation and promoting angiogenesis, collagen deposition, and the growth of granulation tissue, leading to a better curative effect than the commercial gauze and Atrauman. Ag in infected and uninfected wounds. Thus, the multifunctional dynamic enamine‐based hydrogel with on‐demand removability has great potential in clinical applications.