Rapid synthesis of oxygen-defected molybdenum oxides quantum dots as efficient nanozymes for healing diabetic ulcers

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.