Self-healing hydrogels with multifunctionality as a type of fascinating material show potential application in various fields, such as biomedicine, tissue engineering, and wearable electronic devices. However, to combine the properties of autonomous self-healing property, high conductivity, excellent mechanical properties, and stimuli-responsive properties for hydrogel is still a great challenge. Herein, we present self-healing conductive hydrogels based on β-cyclodextrin (β-CD), Nisopropylacrylamide (NIPAM), multiwalled carbon nanotubes (CNT) and nanostructured polypyrrole (PPY). Among them, β-CD served as the host molecule, and NIPAM served as the guest molecule, CNT as the physical cross-linker and conducting substrate, and PPY as the highly conductive component, respectively. The obtained hydrogels exhibit high conductivity, selfhealing property, flexible and elastic mechanical property and rapid stimuli-responsive property both to temperature and nearinfrared (NIR)-light together. The excellent characteristics of the hydrogels are further illustrated by pressure-dependent sensors, large-scale human motion monitoring sensors and self-healable electronic circuit. Cytotoxicity test indicated that they are nontoxic to L929 fibroblast cells and C2C12 myoblast cells. Taken together, these multifunctional hydrogels are excellent candidates for stimuli responsive electrical devices, artificial organs, and so on.

Diabetic wound healing and angiogenesis remain a worldwide challenge for both clinic and research. The use of adipose stromal cell derived exosomes delivered by bioactive dressing provides a potential strategy for repairing diabetic wounds with less scar formation and fast healing. In this study, we fabricated an injectable adhesive thermosensitive multifunctional polysaccharide-based dressing (FEP) with sustained pH-responsive exosome release for promoting angiogenesis and diabetic wound healing. The FEP dressing possessed multifunctional properties including efficient antibacterial activity/multidrug-resistant bacteria, fast hemostatic ability, self-healing behavior, and tissue-adhesive and good UV-shielding performance. FEP@exosomes (FEP@exo) can significantly enhance the proliferation, migration, and tube formation of endothelial cells in vitro. In vivo results from a diabetic full-thickness cutaneous wound model showed that FEP@exo dressing accelerated the wound healing by stimulating the angiogenesis process of the wound tissue. The enhanced cell proliferation, granulation tissue formation, collagen deposition, remodeling, and re-epithelialization probably lead to the fast healing with less scar tissue formation and skin appendage regeneration. This study showed that combining bioactive molecules into multifunctional dressing should have great potential in achieving satisfactory healing in diabetic and other vascular-impaired related wounds.

The surgical procedure in skin-tumor therapy usually results in cutaneous defects, and multidrug-resistant bacterial infection could cause chronic wounds. Here, for the first time, an injectable self-healing antibacterial bioactive polypeptide-based hybrid nanosystem is developed for treating multidrug resistant infection, skin-tumor therapy, and wound healing. The multifunctional hydrogel is successfully prepared through incorporating monodispersed polydopamine functionalized bioactive glass nanoparticles (BGN@ PDA) into an antibacterial F127-ε-Poly-L-lysine hydrogel. The nanocomposites hydrogel displays excellent self-healing and injectable ability, as well as robust antibacterial activity, especially against multidrug-resistant bacteria in vitro and in vivo. The nanocomposites hydrogel also demonstrates outstanding photothermal performance with (near-infrared laser irradiation) NIR irradiation, which could effectively kill the tumor cell (>90%) and inhibit tumor growth (inhibition rate up to 94%) in a subcutaneous skin-tumor model. In addition, the nanocomposites hydrogel effectively accelerates wound healing in vivo. These results suggest that the BGN-based nanocomposite hydrogel is a promising candidate for skin-tumor therapy, wound healing, and antiinfection. This work may offer a facile strategy to prepare multifunctional bioactive hydrogels for simultaneous tumor therapy, tissue regeneration, and anti-infection.

Overcoming the multidrug-resistant (MDR) bacterial infection is a challenge and urgently needed in wound healing. Few wound dressings possess the capacity to treat MDR bacterial infections and enhance wound healing. Herein, we develop an elastomeric, photoluminescent, and antibacterial hybrid polypeptide-based nanofibrous matrix as a multifunctional platform to inhibit the MDR bacteria and enhance wound healing. The hybrid nanofibrous matrix was composed of poly­(citrate)-ε-poly lysine (PCE) and poly caprolactone (PCL). The PCL–PCE hybrid nanofibrous matrix showed a biomimetic elastomeric behavior, robust antibacterial activity including killing MDR bacteria capacity, and excellent biocompatibility. PCL–PCE nanofibrous system can efficiently prevent the MDR bacteria-derived wound infection and significantly enhance the complete skin-thickness wound healing and skin regeneration in a mouse model. PCL–PCE hybrid nanofibrous matrix might become a competitive multifunctional dressing for bacteria-infected wound healing and skin regeneration.