(a) Illustration of the experiment procedure for the pathways investigations associated with glymphatic drainage. The WT mice were pretreated with ACZ or TGN-020 for a certain period to generate modeled mice, then received i.c. injection of AuNCs and their brains with CLNs were collected for analysis. (b) The FLI of brains with AuNCs distribution after ACZ pretreatment, the color scale ranges from 5.0 × 108 to 1.0 × 109. (c) The FLI of the CLNs, the color scale ranges from 2.0 × 107 to 5.0 × 107. The semi-quantification of the fluorescent intensity in brains for AuNC@BSA (d) and AuNC@GSH (e), and their Au contents in brain quantified by the ICP-MS (f, g, respectively). The fluorescent intensity in CLNs were also semi-quantified (h, i). (j) The confocal imaging of AuNCs (green and red) internalized by peri-artery macrophages (pink), with blue indicates the nuclei. The white bar represents 5 μm. The white arrows indicate the post-internalization AuNCs in the macrophages. (k) The FLI of brains with AuNCs distribution after TGN-020 pretreatment, the color scale ranges from 1.0 × 108 to 1.6 × 109 for AuNC@BSA, and 1.0 × 108 to 1.0 × 109 for AuNC@GSH. (l) The FLI of the CLNs, the color scale ranges from 3 × 107 to 7 × 107. The semi-quantification of fluorescent intensity (m, n) and ICP-MS quantification (o, p) of AuNCs in brains, and the fluorescent intensity in CLNs containing AuNCs (q, r). The unit for fluorescent imaging is (p/sec/cm2/sr)/(μW/cm2).