Characterizations of Fe2O3@DMSA and Fe2O3@APTS, and their internalized distribution. A,B) TEM images of Fe2O3@DMSA and Fe2O3@APTS. C,D) SEM images of Fe2O3@DMSA and Fe2O3@APTS. E) FTIR spectra of Fe2O3@DMSA and Fe2O3@APTS. F) Zeta potential of Fe2O3@DMSA and Fe2O3@APTS. G,H) Cellular uptake of Fe2O3@DMSA and Fe2O3@APTS in SK‐Hep‐1 and HepG2 cells were determined by flow cytometry after exposure for 24 h at the doses of 20, 200, 300 µg mL−1, respectively. The data represented mean ± standard deviation (SD). *p < 0.05, **p < 0.01, and ***p < 0.001 compared with control. #
p < 0.05, ##
p < 0.01, and ###
p < 0.001 between the indicated groups. I) TEM images of internalized Fe2O3@DMSA. The red arrows indicated early autophagic vesicles with double membrane. J) TEM images of internalized Fe2O3@APTS. The blue arrows indicated degradative autophagic vesicles with single membrane. DMSA denotes Fe2O3@DMSA. APTS denotes Fe2O3@APTS.