Immobilized transferrin Fe₃O₄@SiO₂ nanoparticle with high doxorubicin loading for dual-targeted tumor drug delivery

Figures & data

Figure 1 Route for generation of transferrin immobilized Fe₃O₄ magnetic nanoparticles with high doxorubicin load.

Abbreviations: TEOS, tetraethyl orthosilicate; APS, 3-aminopropyltrimethoxysilane; GA, N-phthaloyl-L-glutamic acid anhydride; PLGA, poly-L-glutamic acid; EDC, 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride; NHS, N-hydroxysuccinimide; Tf, transferrin; DOX, doxorubicin; DMP, dual-function magnetic nanoparticle; DDMP, DOX-coupled DMP; TfDMP, DDMP with immobilized Tf.

Figure 2 ATR-IR spectra.

Notes: (A) Fe₃O₄; (B) DMP; (C) TfDMP; (D) DOX; (E) Tf.

Abbreviations: ATR-IR, attenuated total reflection infrared; DMP, dual-function magnetic nanoparticle; DOX, doxorubicin; Tf, transferrin; TfDMP, DOX-coupled DMP with immobilized Tf.

Figure 3 DOX loading percentage at different DOX/DMP ratios.

Abbreviations: DOX, doxorubicin; DMP, dual-function magnetic nanoparticle.

Figure 4 Magnetic properties of TfDMP.

Notes: (A) TfDMP suspended in aqueous solution before and 1 hour after a magnet is placed outside the test tube. (B) Magnetization versus field curve for TfDMP at 27°C.

Abbreviations: TfDMP, doxorubicin-coupled dual-function magnetic nanoparticle with immobilized transferrin; M, magnetization; emu, magnetic moment; H, field; Oe, oersted.

Figure 5 TfDMP characteristics.

Notes: (A) Transmission electron micrograph of TfDMP. (B) Size distribution plot of TfDMP, obtained by dynamic light scattering.

Abbreviation: TfDMP, doxorubicin-coupled dual-function magnetic nanoparticle with immobilized transferrin.

Figure 6 DOX release from TfDMP at different pH levels.

Note: TfDMP in phosphate-buffered saline solution at 37°C.

Abbreviations: DOX, doxorubicin; TfDMP, doxorubicin-coupled dual-function magnetic nanoparticle with immobilized transferrin; h, hours.

Figure 7 Comparison DDMP and TfDMP, with both cell lines.

Notes: Mean fluorescence intensity and parent percentage of (A) HeLa and (C) K562 cells after being incubated with DDMP and TfDMP for 1 hour, with a DOX concentration of 2 μg (by flow cytometry). Confocal laser scanning microscopy of (B) HeLa and (D) K562 cells treated with DDMP (upper) and TfDMP (lower), in the presence of a total DOX concentration of 4 μg/mL (after incubation for 2 hours at 37°C). Bars: 10 μm.

Abbreviations: DMP, dual-function magnetic nanoparticle; DOX, doxorubicin; DDMP, DOX-coupled DMP; TfDMP, DOX-coupled DMP with immobilized transferrin; HeLa, Henrietta Lacks strain of cancer cells; K562, human leukemia cell line.

Figure 8 Cytotoxic effects of DMP, DDMP, Tf, and TfDMP, in HeLa and K562 cells.

Abbreviations: DMP, dual-function magnetic nanoparticle; DDMP, doxorubicin-coupled DMP; TfDMP, doxorubicin-coupled DMP with immobilized transferrin, Tf, transferrin; IC₅₀, half maximal inhibitory concentration; HeLa, Henrietta Lacks strain of cancer cells; K562, human leukemia cell line.