Fig. 3: The targeting, penetration and drug release kinetics of FAB NPs.

A Molecular docking simulation of 5-ALA and baicalin with HFn. B Targeting ability of FAB NPs towards HSFs. (i) The schematic diagram illustrating the difference in uptake of FAB NPs by normal fibroblasts and HSFs. (ii) Protein and (iii) relative mRNA expression of TFR1 in normal fibroblasts and HSFs (n = 3 biologically independent samples). (iv) Representative fluorescence images of RhB-labeled FAB NPs internalized by normal fibroblasts and HSFs (green, Actin-Tracker Green-stained cytoskeleton; blue, DAPI-stained nucleus; red, RhB-labeled FAB NPs; Scale bar: 10 μm). C The deep penetration of FAB NPs in 3D scarring spheroid model. (i) The fabrication and treatment process of scarring spheroids. (ii) CLSM images of scarring spheroids after different treatments (Green, Fluorescein Isothiocyanate (FITC)-labeled 5-ALA; Red, RhB-labeled baicalin. Scale bar: 50 μm). (iii) 3D surface plot of the 75 μm sections from different groups. D The subcellular location and release profile of FAB NPs. (i) Representative CLSM images of FAB NPs colocalized with lysosomes after endocytosis (green, Lyso-Tracker Green-stained lysosome; blue, Hoechst-stained nucleus; red, RhB-labeled FAB NPs. Scale bar: 5 μm). (ii) Cumulative release profiles of 5-ALA and baicalin from FAB NPs in solutions at different pH values in vitro (n = 3 biologically independent samples). (iii) The FEL of 5-ALA-HFn (left) and baicalin-HFn (right). E Scheme illustrating the therapeutic strategies and characteristics of FAB NPs for HSFs. Data represent the mean ± SD. Two-sided unpaired Student’s t-test was used for the comparison in B (iii). Experiments in (C) were performed thrice independently, yielding similar results each time. Source data are provided as a Source Data file. Schematic in (C) was created using BioRender. Yuan, C. (2025) https://BioRender.com/r1hiu7x.