Protective effect of dexamethasone-loaded sclera nail with connected pore channel on blood-retinal barrier damage

Blood-retinal barrier damage can lead to the progression of various diseases in severity, such as macular edema. Dexamethasone has shown significant therapeutic effects on inflammation and tissue edema. Here, we propose a dexamethasone-loaded chitosan porous scaffold (sclera nail) with connected pore channels prepared by the combination of inorganic salt pore-forming and polysaccharide dissolution. The higher porosity and lower degradation rate endowed the sclera nail with higher drug loading capacity and longer sustained drug release capacity. The compressed scleral nail rapidly expanded (less than 10 s) after absorbing water, which was beneficial for it to quickly seal the surgical incision of the eyes and prevent bacterial infection. And the results of tube formation and important ocular protein expression indicated that the scleral nail had good anti-inflammatory ability and significant anti-angiogenic effects. Scleral nail with long-term release of dexametha-sone are promising for treatment of ocular diseases associated with blood-retinal barrier damage.