Fig. 6: Evaluation of brain-targeting ability.

a Schematic representation of the in vitro construction process for blood-brain barrier (BBB) and the traversal of BBB. Figure 1a Created with BioRender.com released under a Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International license. b Fluorescence intensity of the supernatant liquid in the lower chamber after the introduction of NPs for 4 h (n = 3 independent experimental units). c Fluorescence intensity of nanoparticles taken up by 4T1 cells in the lower chamber (n = 3 independent cell lines). d In vivo imaging of mice bearing with brain-metastatic tumor at 1, 2, 4, 8 h post intravenous injection. e, f Ex vivo imaging of major organs and brains at 8 h post intravenous injection. g, h Semi-quantification of major organs and brains (n = 4 mice). All data are presented as mean ± SD. Two-tailed Student’s t test and One-way analysis of variance (ANOVA) with a Tukey post hoc test were used for the statistical comparison between the two groups and among multiple groups, respectively. A significant difference was considered when the p value was < 0.05. Source data are provided as a Source Data file.