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.

Traditional skin tumor surgery and chronic bacterial-infection-induced wound healing/skin regeneration is still a challenge. The ideal strategy should eliminate the tumor, enhance wound healing/skin formation, and be anti-infection. Herein, we designed a multifunctional elastomeric poly(L-lactic acid)−poly(citrate siloxane)−curcumin@polydopamine hybrid nanofibrous scaffold (denoted as PPCP matrix) for tumorinfection therapy and infection-induced wound healing. The PPCP matrix showed intrinsically multifunctional properties including antioxidative, anti-inflammatory, photothermal, antibacterial, anticancer, and angiogenesis bioactivities. The polydopamine/curcumin presented an excellent near-infrared photothermal/cancer cell toxicity capacity, respectively, which supported PPCP for synergetic skin tumor therapy and antibacterial properties in vitro/in vivo. Additionally, the PPCP nanofibrous matrix significantly promotes the adhesion and proliferation of normal skin cells and accelerates the cutaneous wound healing in normal mice and bacterial-infected mice by enhancing the early angiogenesis. The PPCP nanofibrous matrix with multifunctional bioactivities provides a competitive strategy for skin tumor and bacterial-infection-induced wound healing.

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.

In recent years, microbial colonization on the surface of biomedical implants/devices has become a severe threat to human health. Herein, surface-immobilized guanidine derivative block copolymers create an antimicrobial and antifouling dual-functional coating. We report the preparation of an antimicrobial and antifouling block copolymer by the conjugation of polyhexanide (PHMB) with either allyl glycidyl ether or allyloxy polyethylene glycol (APEG; MW 1200 and 2400). The allyl glycidyl ether modified PHMB (A-PHMB) and allyloxy polyethylene glycol modified PHMB (APEG-PHMB) copolymers were grafted onto a silicone rubber surface as a bottlebrush-like coating, respectively, using a plasma-UV-assisted surface-initiated polymerization. Both A-PHMB and APEG-PHMB coatings exhibited excellent broad-spectrum antimicrobial properties against Gram-negative/positive bacteria and fungi. The APEG-PHMB coating displayed an improved antibiofilm as well as antifouling properties and a long reusable cycle, compared with two other coatings, due to its abundant PEG blocks among those copolymers. Also, the APEG-PHMB-coated silicone coupons were biocompatible toward mammalian cells, as revealed by in vitro hemocompatibile and cytotoxic assays. An in vivo study showed a significant decline of Escherichia coli colonies with a 5-log reduction, indicating the APEG-PHMB coating surface worked effectively in the rodent subcutaneous infection model. This PHMB-based block copolymer coating is believed to be an effective strategy to prevent biomaterial-associated infections.