Effect and mechanism of paclitaxel loaded on magnetic Fe₃O₄@mSiO₂-NH₂-FA nanocomposites to MCF-7 cells

Figures & data

Figure 1. SEM morphology (A), TEM image (B), XRD pattern (C), XPS survey scan spectrum (D), XPS spectra of Fe2p (E), Hysteresis loop (F), FTIR spectra (G), EDS spectrum (H), and BET measurement (I) of magnetic Fe₃O₄ nanoparticles heated at 170 °C for 24 h with a heating rate of 3 °C/min.

Figure 2. TEM image of Fe₃O₄ nanoparticles heated at 170 °C for 24 h (A) and Fe₃O₄@mSiO₂ nanoparticles (B), and the FTIR spectra of the process of magnetic Fe₃O₄ nanoparticles coated with silica (C).

Figure 3. FTIR spectra (A), Hysteresis loop (B), and the change of surface zeta potential (C) of Fe₃O₄, Fe₃O₄@mSiO₂, Fe₃O₄@mSiO₂-NH₂, Fe₃O₄@mSiO₂- NH₂-FA; The Nitrogen adsorption-desorption curve (D), and pore size distribution (E) of Fe₃O₄@mSiO₂-NH₂-FA.

Figure 4. The toxicity of Fe₃O₄ (A) and Fe₃O₄@mSiO₂-NH₂-FA (B) to cells at different time points and the toxicity of Fe₃O₄@mSiO₂-NH₂-FA to cells with or without an external magnetic field (C) (n = 3, * P < .05, ** P < .01, compared with the control group, # P < .05, ## P < .01, comparison between groups).

Figure 5. Prussian blue staining of MCF-7 cells: blank group (A, C), 40 μg/mL magnetic Fe₃O₄@mSiO₂-NH₂-FA nanocomposites (B, D).

Figure 6. Cytotoxicity of free TAX and magnetic Fe₃O₄@mSiO₂-NH₂-FA-TAX nanocomposites (with and without a magnetic field) to MCF-7 cells at 24 h (A), 48 h (B), 72 h (C) (n = 3, ** P < .01, compared with the control group, # P < .05, ## P < .01, comparison between groups).

Figure 7. The AO/EB double staining fluorescence images of MCF-7 cells treated with blank control (A), Fe₃O₄@mSiO₂-NH₂-FA-TAX nanocomposites without MF (B), free TAX (C), and Fe₃O₄@mSiO₂-NH₂-FA-TAX nanocomposites with MF (D) for 24 h.

Figure 8. Flow cytometry scatter plots of Annexin V-FITC/PI apoptosis staining: (A) Control, (B) Fe₃O₄, (C) Fe₃O₄@mSiO₂-NH₂-FA, (D) Fe₃O₄@mSiO₂-NH₂-FA-TAX, (E) Free TAX, and (F) Fe₃O₄@mSiO₂-NH₂-FA-TAX + MF.

Figure 9. Detection of ROS in MCF-7 cells treated by blank control group (A1), Fe₃O₄ (A2), Fe₃O₄@mSiO₂-NH₂-FA (A3), Fe₃O₄@mSiO₂-NH₂-FA-TAX (A4), free TAX (A5), and Fe₃O₄@mSiO₂-NH₂-FA-TAX with magnetic field (A6), respectively. Detection of SOD level (B1) and MDA level (B2) in MCF-7 cells treated by blank control group, Fe₃O₄ (M), Fe₃O₄@mSiO₂-NH₂-FA (M-FA), free TAX, Fe₃O₄@mSiO₂-NH₂-FA-TAX (M-FA-TAX), and Fe₃O₄@mSiO₂-NH₂-FA-TAX with MF, respectively (n = 3, ** P < .01, compared with the control group, ## P < .01, comparison between groups).

Figure 10. Effects of apoptosis related protein expression levels in MCF-7 cells treated with different groups (A). Where M represents Fe₃O₄@mSiO₂-NH₂-FA, M-TAX represents Fe₃O₄@mSiO₂-NH₂-FA, and MF represents magnetic field action (n = 3, ** P < .01, compared with the control group, # P < .05, ## P < .01, comparison between groups). Effects of ferroptosis related protein expression levels in MCF-7 cells treated with different groups (B). Where M represents Fe₃O₄@mSiO₂-NH₂-FA, M-TAX represents Fe₃O₄@mSiO₂-NH₂-FA, MF means magnetic field action (n = 3, ** P < .01, compared with the control group, # P < .05, ## P < .01, comparison between groups).

Figure 11. Effect of MCF-7 cell activity treated by Fe₃O₄@mSiO₂-NH₂-FA-TAX under the action of magnetic fields with and without NAC treatment (n = 3, ** P < .01, compared with the control group, # P < .05, ## P < .01, comparison between groups).

Figure 12. Level of ROS detected by DCFH-DA probe.

Figure 13. Effects of apoptosis and ferroptosis related protein expression levels in MCF-7 cells treated by Fe₃O₄@mSiO₂-NH₂-FA-TAX under the action of magnetic fields with and without NAC treatment. (−) means not treated by NAC, (+) means treated by NAC (n = 3, **P < .01, comparison between groups).

Data availability statement

The data and materials generated and analyzed during the current study are available from the corresponding author on reasonable request.