Figure 3.

In vitro PTX release from and retained in ZGO@TiO₂@ALP‐NEs a) without and b) with ultrasound irradiation. The arrows represent the application of ultrasound (5 min, 1.5 W cm⁻², 1.5 MHz) at the 0.5 h time point. c) Cytotoxicity evaluation against GL261 cells. d) In vitro BBB penetration of ZGO@TiO₂@ALP‐NEs under tumor attraction. Quantities of PTX were determined in the supernatant (non‐penetrated), endothelial layer (intracellular), and filtrate (penetrated); PTX distribution in the transwell chamber after incubation e) in the absence and f) in the presence of GL261 cells for 6 h. Data are given as mean ± s.d. (n = 4). g) Tumor penetration ability of ZGO@TiO₂@ALP‐NEs. Scale bar, 100 µm. bEnd.3 cell nucleus were stained with Hoechst 33342. The GL261 and bEnd.3 membrane were labelled with DiO (green).