Construction of cascade multifunctional nanoplatform with photo-responsiveness and pH switchable enzyme-like activity through confined growth strategy for diabetic wound therapy

In the complex microenvironment, bacterial infection, persistent inflammation and angiogenesis disorder collectively lead to difficult wound healing in infectious diabetes. This study constructed a multifunctional cascade nanoplatform (Au-Ru/g-C 3 N 4 @PZ-UiO66-NH 2 , ARPZU) with photo-responsiveness and pH switchable enzyme-like activity for the treatment of diabetes wounds at different infectious stages. In the initial acidic environment of infection, the shell (PZ-UiO66-NH 2 ) of prepared nanoplatform underwent self-dissociation to release the encapsulated core (Au-Ru/g-C 3 N 4 ). Under near-infrared light irradiation, Au Ru bimetallic centers with glucose oxidase-like activities synergistically catalyzed the generation of reactive oxygen species, achieving blood glucose reduction and pathogen clearance. In the late neutral environment of infection, Ru active center could effectively clear reactive oxygen species (ROS), meanwhile continuously produced O 2 through superoxide dismutase-like and catalase-like activities, which significantly inhibited inflammatory responses. In addition, the presence of Zn 2+ and PO 4 3− from the decomposition of PZ-UiO66-NH 2 framework effectively promoted the regeneration and repair of blood vessels. In vivo and vitro results further confirmed that the prepared ARPZU using growth strategy could finally achieve wound healing of diabetes with the help of adaptive cascade reaction and programmed function. This study provided a new idea for development of multifunctional nanoplatform.