(a) The structure of chip used for the construction of the dynamic BBB model. The brain vascular endothelia grew to interior cover in apical chamber with permanent flow to simulate brain blood vessel, and astrocytes grew in the basolateral chamber with conditional flow (commonly flowed off when experimented) to support the dynamic BBB model, bar represents 200 μm. (b) The real-time fluorescent imaging captured the permeability of AuNCs in the direction of blood to brain (i: AuNC@BSA, ii: AuNC@GSH) or brain to blood (iii: AuNC@BSA, iv: AuNC@GSH), the white bar represents 200 μm, BF = bright field, green fluorescence tracks the FITC on the AuNCs. (c-f) The permeability to time graphs were obtained from a-d, respectively. The permeability rates revealed the efficacy in linear phase. Fluorescent imaging of the WT and GW6849-treated mice brain (g) and CLNs (h), the scale bars range from 2.0 × 107 to 1.2 × 108, and 4.0 × 106 to 1.0 × 107, respectively. The semi-quantification of fluorescence in brain (i, j) and CLNs (m, n), and remaining Au quantified by ICP-MS (k, l) revealed the elimination of AuNCs and glymphatic drainage. The unit for fluorescent imaging is (p/sec/cm2/sr)/(μW/cm2).