Fig. 2: The synthesis and characterization of FAB@MN.

A Schematic illustration of steps for the preparation of FAB@MN. B TEM and C digital images of HFn and FAB NPs solutions (Scale bar: 20 nm). D DLS and Zeta potential analysis (n = 3 biologically independent samples). E UV-Vis spectra of 5-ALA, baicalin, HFn and FAB NPs. F Native-PAGE characterization. G (i) The SEC and (ii) CD analysis of HFn, FA NPs, FB NPs and FAB NPs. H The schematic diagram of MN fabrication and transdermal drug delivery. I Digital photos and J mechanical compression test of PVP MN and FAB@MN patches. K SEM image of FAB@MN. L Typical images of rabbit HS skin after applying FAB@MN (Scale bar: 2 mm). M (i) Fluorescent photograph of FAB@MN (FAB NPs were labeled by red RhB) (Scale bar: 50 μm) and (ii) the distribution of RhB-labeled FAB NPs in the depths of rabbit HS after FAB@MN insertion for 5 min (Scale bar: 100 μm). Data represent the mean ± SD and a two-sided unpaired Student’s t-test was used for the comparison in (D). Experiments in (B), (F), (K), and (M) were each performed thrice independently, yielding similar results each time. Source data are provided as a Source Data file.