Fig. 1

Illustration to demonstrate the structure and mechanism of PP@BSA-TAFeⅢ NPs

Table 1

Experimental reagents and materials

Table 2

Experimental instruments

Fig. 2

Characterization of PP@BSA-TAFeIII NPs. (a) TEM images of PP NPs, PP@BSA NPs and PP@BSA-TAFeIII NPs; (b) TEM mapping image of PP@BSA-TAFeIII NPs; (c) Size distribution and (d) zeta potential of PP NPs, PP@BSA NPs and PP@BSA-TAFeIII NPs; (e) UV-vis absorption spectra of different nanoparticles (concentration of PFCE is 2 mmol/L); (f) FT-IR spectra of PP@BSA-TA NPs and PP@BSA-TAFeIII NPs (concentration of PFCE is 100 mmol/L)

Fig. 3

In vitro characterization of PP@BSA-TAFeIII NPs. (a) pH-dependent release of Fe3+ by PP@BSA-TAFeIII NPs solution; (b) Temperature variation curves of PP@BSA-TAFeIII NPs solutions with different concentrations under the irradiation of 808 nm laser with 1.0 W·cm-2; (c) Temperature variation curves of PP@BSA-TAFeIII NPs solutions under the cyclic irradiation of 808 nm laser with 1.0 W·cm-2; (d) Gel electrophoresis of proteins adsorbed on PP@BSA-TAFeIII NPs (Probe), PP@BSA-TA NPs and PP@BSA NPs treated with FBS; (e) Quantitative detection of transferrin adsorbed on different nanoparticles by ELISA; (f) 19F MRI images of PP@BSA-TAFeIII NPs solutions at different concentrations, and the linear fitting curve of signal intensity versus concentration

Fig. 4

CLSM images of 4Tl cells treated with PP@BSA-TAFeIII NPs+FBS, PP@BSA-TAFeIII NPs and PP@BSA NPs + FBS. Cell nuclei was stained by DAPI, and cytoskeleton was stained by FITC- phalloidin

Fig. 5

In vitro antitumor efficacy of PP@BSA-TAFeIII NPs. (a) Viabilities of 4T1 cells treated with different nanoparticles; (b) CLSM images of ROS levels in 4Tl cells treated with different concentrations of Fe3+ in PP@BSA-TAFeIII NPs (cell nuclei was stained by Hoechst 33342); (c) TEM images of 4T1 cells treated with PP@BSA-TAFeIII NPs for different times; (d) CLSM images of 4T1 cells stained with Calcein-AM/PI (green fluorescence for live cells, red fluorescence for dead cells) after treatment with different concentrations of Fe3+ in PP@BSA-TAFeIII NPs and irradiation with 808 nm laser (1 W·cm-2) for 10 min

Fig. 6

In Vivo tumor MR imaging and antitumor effect of PP@BSA-TAFeIII NPs. (a) 19F MRI images of 4T1 tumor-bearing mice after intravenous injection of PP@BSA-TAFeIII NPs or PP NPs for 12 h; (b) Infrared thermal photographs of the 4T1 tumor-bearing mice after intravenous injection of PBS, PP@BSA NPs or PP@BSA-TAFeIII NPs, followed by irradiation with 808 nm laser (1 W·cm-2); (c) Schematic illustration of the in vivo antitumor therapy; (d) Tumor volume growth curves, (e) body weight change curves and (f) tumor photographs of mice in different treatment groups; (g) H&E staining and TUNEL staining images of tumor tissues from mice in different treatment groups