The emerging applications of magnetic nanovectors in nanomedicine

Cytocompatibility of pH-sensitive, chitosan-coated Fe3O4 nanoparticles in gynecological cells

Nanoparticles that contact human cells without damaging basic human tissues are becoming more widely used in medicine. Efficient delivery to the intracellular target cell or compartment through the cell membrane must be achieved with minimal cytotoxicity to healthy cells. Fe₃O₄ nanoparticles have been widely used in biomedical research for their magnetic, non-toxic, and biocompatible properties. However, the effects of Fe₃O₄ nanoparticles coated with chitosan (CS) on gynecological cells are unclear. In this study, the Fe₃O₄ nanoparticles were coated with CS to enhance their cytocompatibility and dispersion in water. These CS-Fe₃O₄ nanoparticles were taken up by gynecological cells and did not affect cell viability in vitro. They have greater cytocompatibility in acidic environments than normal Fe₃O₄ nanoparticles and have the potential for drug delivery into gynecological cells.

cRGD-Conjugated Fe3O4@PDA-DOX Multifunctional Nanocomposites for MRI and Antitumor Chemo-Photothermal Therapy

Background

Photothermal therapy (PTT) has great potential in the clinical treatment of tumors. However, most photothermal materials are difficult to apply due to their insufficient photothermal conversion efficiencies (PCEs), poor photostabilities and short circulation times. Furthermore, tumor recurrence is likely to occur using PTT only. In the present study, we prepared cyclo (Arg-Gly-Asp-d-Phe-Cys) [c(RGD)] conjugated doxorubicin (DOX)-loaded Fe₃O₄@polydopamine (PDA) nanoparticles to develop a multifunctional-targeted nanocomplex for integrated tumor diagnosis and treatment.

Materials and methods

Cytotoxicity of Fe₃O₄@PDA-PEG-cRGD-DOX against HCT-116 cells was determined by cck-8 assay. Cellular uptake was measured by confocal laser scanning microscope (CLSM). Pharmacokinetic performance of DOX was evaluated to compare the differences between free DOX and DOX in nanocarrier. Performance in magnetic resonance imaging (MRI) and antitumor activity of complex nanoparticles were evaluated in tumor-bearing nude mice.

Results

Fe₃O₄@PDA-PEG-cRGD-DOX has a particle size of 200–300 nm and a zeta potential of 22.7 mV. Further studies in vitro and in vivo demonstrated their excellent capacity to target tumor cells and promote drug internalization, and significantly higher cytotoxicity with respect to that seen in a control group was shown for the nanoparticles. In addition, they have good thermal stability, photothermal conversion efficiencies (PCEs) and pH responsiveness, releasing more DOX in a mildly acidic environment, which is very conducive to their chemotherapeutic effectiveness in the tumor microenvironment. Fe₃O₄@PDA-PEG-cRGD-DOX NPs were used in a subcutaneous xenograft tumor model of nude mouse HCT-116 cells showed clear signal contrast in T2-weighted images and effective anti-tumor chemo-photothermal therapy under NIR irradiation.

Conclusion

According to our results, Fe₃O₄@PDA-PEG-cRGD-DOX had a satisfactory antitumor effect on colon cancer in nude mice and could be further developed as a potential integrated platform for the diagnosis and treatment of cancer to improve its antitumor activity against colon cancer.