Overexpression of reactive oxygen species (ROS) can lead to chronic inflammation, which limits skin wound healing. Therefore, it is of great significance to develop materials that can locally control the adverse reactions caused by excessive ROS. In this research, an ROS-sensitive hydrogel with strong free radical scavenging ability was prepared by introducing the thione (Tk) group into carboxymethyl chitosan (CMCTS) hydrogel. CMCTS hydrogel was cross-linked by NH2-Tk-NH2 agent and loaded curcumin (Cur), which possessed favorable nontoxicity, water absorption, mechanical property, biodegradability, drug release behavior, the M2 phenotype, and inflammatory factor regulating the capacity of macrophages. It is worth noting that Cur@CMCTS-Tk hydrogel can significantly inhibit oxidative damage of human fibroblasts in the H2O2-induced microenvironment and protect their viability by reducing the production of intracellular ROS. In vivo, ROS-removing hydrogel effectively accelerated the process of wound healing and possessed good regenerative properties, including hair follicle formation, promotion of new blood vessel formation, and highly orderly arrangement of collagen fibers in the full-thickness skin burn defect rat model. Hence, we expect that the Cur@CMCTS-Tk hydrogel could be used for wound treatment and tissue regeneration due to the ability to scavenge excess ROS.

Hydrogel dressings have attracted extensive attention owing to the similarity in their softness to that of the extracellular matrix, adjustability of physicochemical properties, and ability to remain moist even at the wound site. However, developing composite hydrogel with excellent mechanical behavior, adhesiveness to tissues, good biocompatibility, long‐term antibacterial properties, and enhanced vascularization capacity continues to be a great challenge. Herein, a novel nanocomposite hydrogel based on the photo‐cross‐linking of poly(ethylene glycol)diacrylate (PEGDA), thiolated chitosan (TCS), and modified polyhedral oligomeric silsesquioxane (POSS) nanoparticles is designed. Moreover, silver ions (Ag+) are loaded into the system via dynamic coordination of Ag–S. The resultant PEGDA/TCS/POSSP@Ag hydrogel presents high toughness, strength, and good tissue adhesiveness and facilitates the attachment and proliferation of human umbilical vein endothelial cells (HUVCEs) in vitro. As a controlled release carrier of the bacteria‐killing activity of Ag+, the composite system achieves controlled release of Ag+ and good antibacterial activity. Further in vivo experiments demonstrated that the PEGDA/TCS/POSSP@Ag scaffolds significantly promote skin regeneration by reducing inflammation and inhibiting infection, a rat model with full‐thickness skin defects verified its ability to stimulate microvascular formation due to activation of POSS. Thus, the multi‐functional nanocomposite hydrogel is a highly promising dressing material for wound healing.

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Giant surfactants with different numbers of aryl-trifluorovinyl ether-functionalized polyhedral oligomeric silsesquioxane (FVPOSS) heads and one poly­(ethylene oxide) (PEO) tail, (FVPOSS) n –PEO227, are precisely synthesized. The phase behaviors of (FVPOSS) n –PEO227 at the air–water interface were investigated through surface pressure measurements (isotherm and hysteresis experiments) and the Brewster angle microscopy. Upon increasing the number of FVPOSS heads, the interfacial behaviors of these giant surfactants greatly change. More phase transitions occur during the compression as the number of FVPOSS heads increased from one to two and three. The evolution of morphologies of Langmuir films and compression–expansion hysteresis curves further illustrate phase transitions at the air–water interface. Furthermore, molecular mechanisms to describe phase transitions of (FVPOSS) n –PEO227 at the interface are put forward. This study deepens the understanding of interfacial phase behaviors of special giant surfactants and provides knowledge of nanostructure design and construction at the interface.