Subconjunctival injection of novel antioxidant nanoparticles inhibits neovascularization after corneal injury

To mitigate corneal neovascularization, we developed antioxidant nanoparticles (BP@CS) that sustainably inhibit the overexpression of reactive oxygen species (ROS) after corneal chemical injury. Immunofluorescence and Western blot were conducted in a mouse corneal alkali burn model to verify the correlation between ROS and neovascularization. Chitosan nanoparticles were loaded with strong reductive black phosphorus quantum dots (BPQDs) using an ionic cross-linking method. Physicochemical properties were characterized by transmission electron microscope (TEM), Zeta potential, Raman spectroscopy. In vitro, CCK8, drug release and cell co-culture experiments were conducted to assess the nanoparticles’ cytotoxicity and antioxidant capacity. In vivo, small animal in vivo imaging, HE, Masson, Immunofluorescence staining, front segment photo and Western blot were used to evaluate efficacy and biosafety. BP@CS nanoparticles have shown great anti-angiogenic activity and biocompatibility in vitro. In vivo, BP@CS was administered by subconjunctival injection in mouse neovascularization model. With the continuous antioxidant activity by BP@CS, the corneal neovascularization has been inhibited. The administration of BP@CS nanoparticles for sustained ROS regulation through local subconjunctival injection represents a new approach to the treatment of pathological corneal neovascularization.