The continuous inflammatory response in diabetic skin wounds leads to excessive production of reactive oxygen species, which cause a vicious circle of long-term inflammation. In the therapeutic research of metal nanoenzymes for healing diabetic ulcers, it still faces the challenges in poor nanoenzymes activity and low-efficient therapeutic efficiency. Herein, ultrasmall oxygen-deficient MoO_3−X quantum dots were fabricated and employed as nanoenzymes for healing fiabetic ulcers. After PEGylation, PEGylated MoO_3−X quantum dots (MoO_3−X/PEG) with oxygen vacancies exhibits excellent photothermal, peroxidase/catalase-like activities. In addition, these MoO_3−X/PEG showed superior properties in scavenging H₂O₂ and effectively inhibiting the scavenging of reactive oxygen species. More importantly, such an oxygen-defected MoO_3−X/PEG had obvious antibacterial and skin repairing effects on alleviating hypoxia and excessive oxidative stress even in a mouse model of diabetic ulcers, inhibiting proinflammatory cytokines and significantly accelerating the healing of infected wounds, which shows great application potential for promoting wound healing. This work highlights that the developed oxygen defected molybdenum oxide compounds capable of peroxidase-like and catalase-like activities show great application potential for healing diabetes wound.

The repair and treatment of tumor bone defects is a difficult problem to solve urgently in clinical medicine. After tumor resection, patients are not only faced with a large area of bone defect, but also may have the risk of tumor recurrence, which can easily cause huge physical and mental harm to patients. In this study, we successfully designed and constructed an organic/inorganic composite microgel bone powder (S-H-M_3%Ce/3%Se) based on cerium (Ce) and selenium (Se) elements co-doped mesoporous bioactive glass (M_3%Ce/3%Se), sodium alginate (SA), and recombinant human-like collagen (HLC). The obtained S-H-M_3%Ce/3%Se could inhibit the growth of osteoma cells and promote the growth of normal cells, and effectively promote the repair of defect bone. The integration of the “treatment and repair” organic/inorganic composite microgel bone powder provided a new strategy for the treatment of cancerous bone defects.

Solar dermatitis is an acute or chronic high incidence of skin injury caused by ultraviolet (UV) radiation based on strong sunlight, which seriously endangers people's health. In this study, we designed and demonstrated enzyme-catalyzed semi-inter penetrating polymer network (Semi-IPN) sprayable nanodrug-loaded hydrogels based on gelatin, 3-(4-hydroxyphenyl) propionic acid (HPA), polyvinyl alcohol (PVA), glycerol, and dexamethasone sodium phosphate (DEXP) for solar dermatitis. The hydrogels had high water content, excellent biocompatibility, effective encapsulation and sustained release of nanodrugs, anti-inflammatory, and strong anti-ultraviolet B (anti-UVB) radiation properties based on glycerol and phenol functional groups, but also controllable spray gelation mode to make them adhere well on the dynamic skin surfaces and achieve continuous transdermal drugs delivery for solar dermatitis. The sprayable nanodrug-loaded hydrogel systems could be used as a highly effective therapeutic method for solar dermatitis, and also provide a good strategy for designing novel nanodrug-loaded hydrogel delivery systems.