Blood–Brain Barrier Permeability Assay

After perfusion, brain tissues of core and penumbra were weighed and added with formamide (Sigma, Shanghai, China), incubated at room temperature for 72 hours, the supernatant was centrifuged at 4°C for 15 minutes (12 000g) and transferred to the 96-well blackboard. The concentration of EB was measured at 620 nm by using a fluorescent multi-well plate reader (Infinite M200OTECAN, Switzerland). The tissue is oven-dried at 120°C for 24 hours and then weighed. The EB content of the tissue was quantified by the linear standard curve derived from the known dye content and then normalized to the tissue weight (μg/g).