Magnetic nanoparticles of ε-Fe1.76 Ga0.24 O3 with the volume-weighted mean size of 17 nm were prepared by thermal treatment of a mesoporous silica template impregnated with metal nitrates and were coated with silica shell of four different thicknesses in the range 6-24 nm. The bare particles exhibited higher magnetization than the undoped compound, 22.4 Am2 kg-1 at 300 K, and were characterized by blocked state with the coercivity of 1.2 T at 300 K, being thus the very opposite of superparamagnetic iron oxides. The relaxometric study of the silica-coated samples at 0.47 T revealed promising properties for MRI, specifically, transverse relaxivity of 89-168 s-1 mmol(f.u.)-1 L depending on the shell thickness was observed. We investigated the effects of the silica-coated nanoparticles on human A549 and MCF-7 cells. Cell viability, proliferation, cell cycle distribution, and the arrangement of actin cytoskeleton were assessed, as well as formation and maturation of focal adhesions. Our study revealed that high concentrations of silica-coated particles with larger shell thicknesses of 16-24 nm interfere with the actin cytoskeletal networks, inducing thus morphological changes. Consequently, the focal adhesion areas were significantly decreased, resulting in impaired cell adhesion.

1st Faculty of Medicine Charles University Prague Czech Republic

Faculty of Chemical Engineering University of Chemistry and Technology Praha Czech Republic

Faculty of Chemical Technology University of Pardubice Pardubice Czech Republic

Faculty of Mathematics and Physics Charles University Praha Czech Republic

Faculty of Medicine in Hradec Králové Charles University Hradec Králové Czech Republic

Institute of Physics Czech Academy of Sciences Praha Czech Republic

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Carr, H. Y., & Purcell, E. M. (1954). Effects of diffusion on free precession in nuclear magnetic resonance experiments. Physics Review, 94, 630-638.

Carroll, M. R. J., Woodward, R. C., House MJ, Teoh, W. Y., Amal, R., Hanley, T. L., & St Pierre, T. G. (2010). Experimental validation of proton transverse relaxivity models for superparamagnetic nanoparticle MRI contrast agents. Nanotechnology, 21, 035103.

Gich, M., Frontera, C., Roig, A., Taboada, E., Molins, E., Rechenberg, H. R., … Nogues, J. (2006). High- and low-temperature crystal and magnetic structures of epsilon-Fe2O3 and their correlation to its magnetic properties. Chemistry of Materials, 18, 3889-3897.

Guo, X., Mao, F., Wang, W., Yang, Y., & Bai, Z. (2015). Sulfhydryl-modified Fe3O4@SiO2 core/shell nanocomposite: Synthesis and toxicity assessment in vitro. ACS Applied Materials & Interfaces, 7, 14983-14991.

Hall, J. E., Fu, W., & Schaller, M. D. (2011). Focal adhesion kinase: Exploring Fak structure to gain insight into function. International Review of Cell and Molecular Biology, 288, 185-225.

Ibrahim, M., Schoelermann, J., Mustafa, K., & Cimpan, M. R. (2018). TiO2 nanoparticles disrupt cell adhesion and the architecture of cytoskeletal networks of human osteoblast-like cells in a size dependent manner. Journal of Biomedical Materials Research. Part A, 106, 2582-2593.

Imperor-Clerc, M., Bazin, D., Appay, M. D., Beaunier, P., & Davidson, A. (2004). Crystallization of beta-MnO2 nanowires in the pores of SBA-15 silicas: In situ investigation using synchrotron radiation. Chemistry of Materials, 16, 1813-1821.

Jin, J., Ohkoshi, S., & Hashimoto, K. (2004). Giant coercive field of nanometer-sized iron oxide. Advanced Materials, 16, 48-51.

Kaman, D. T., Koktan, J., Kuličková, J., Maryško, M., Veverka, P., Havelek, R., … Svoboda, L. (2016). Silica-coated manganite and Mn-based ferrite nanoparticles: A comparative study focused on cytotoxicity. Journal of Nanoparticle Research, 18, 100.

Kohout, J., Brázda, P., Závěta, K., Kubániová, D., Kmječ, T., Kubíčková, L., … Lančok, A. (2015). The magnetic transition in ε-Fe2O3 nanoparticles: Magnetic properties and hyperfine interactions from Mössbauer spectroscopy. Journal of Applied Physics, 117, 17D505.

Královec, K., Havelek, R., Kročová, E., Kučírková, L., Hauschke, M., Bartáček, J., … Sedlák, M. (2019). Silica coated iron oxide nanoparticles-induced cytotoxicity, genotoxicity and its underlying mechanism in human HK-2 renal proximal tubule epithelial cells. Mutation Research, 844, 35-45.

Kubickova, L., Brazda, P., Veverka, M., Kaman, O., Herynek, V., Vosmanska, M., … Kohout, J. (2019). Nanomagnets for ultra-high field MRI: Magnetic properties and transverse relaxivity of silica-coated epsilon-Fe2O3. Journal of Magnetism and Magnetic Materials, 480, 154-163.

Lankoff, A., Arabski, M., Wegierek-Ciuk, A., Kruszewski, M., Lisowska, H., Banasik-Nowak, A., … Slomkowski, S. (2013). Effect of surface modification of silica nanoparticles on toxicity and cellular uptake by human peripheral blood lymphocytes in vitro. Nanotoxicology, 7, 235-250.

Laurent, S., Forge, D., Port, M., Roch, A., Robic, C., Vander Elst, L., & Muller, R. N. (2008). Magnetic iron oxide nanoparticles: Synthesie, Stabilizátor, vectorization, physicochemical characterizations, and biological applications. Chemical Reviews, 108, 2064-2110.

Machala, L., Tucek, J., & Zboril, R. (2011). Polymorphous transformations of nanometric iron(III) oxide: A review. Chemistry of Materials, 23, 3255-3272.

Malvindi, M. A., de Matteis, V., Galeone, A., Brunetti, V., Anyfantis, G. C., Athanassiou, A., … Pompa, P. P. (2014). Toxicity assessment of silica coated iron oxide nanoparticles and biocompatibility improvement by surface engineering. PLoS One, 9, e85835.

Meiboom, S., & Gill, D. (1958). Modified spin-echo method for measuring nuclear relaxation times. Review of Scientific Instruments, 29, 688-691.

Na, H. B., Song, I. C., & Hyeon, T. (2009). Inorganic nanoparticles for MRI contrast agents. Advanced Materials, 21, 2133-2148.

Ohkoshi, S., Kuroki, S., Sakurai, S., Matsumoto, K., Sato, K., & Sasaki, S. (2007). A millimeter-wave absorber based on gallium-substituted epsilon-iron oxide nanomagnets. Angewandte Chemie, 46, 8392-8395.

Patwardhan, S. V., Emami, F. S., Berry, R. J., Jones, S. E., Naik, R. R., Deschaume, O., … Perry, C. C. (2012). Chemistry of aqueous silica nanoparticle surfaces and the mechanism of selective peptide adsorption. Journal of the American Chemical Society, 134, 6244-6256.

Qiao, R. R., Yang, C. H., & Gao, M. Y. (2009). Superparamagnetic iron oxide nanoparticles: From preparations to in vivo MRI applications. Journal of Materials Chemistry, 19, 6274-6293.

Shannon, R. (1976). Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallographica A, 32, 751-767.

Soenen, S. J. H., Himmelreich, U., Nuytten, N., & De Cuyper, M. (2011). Cytotoxic effects of iron oxide nanoparticles and implications for safety in cell labelling. Biomaterials, 32, 195-205.

Soenen, S. J. H., Nuytten, N., De Meyer, S. F., De Smedt, S. C., & De Cuyper, M. (2010). High intracellular iron oxide nanoparticle concentrations affect cellular cytoskeleton and focal adhesion kinase-mediated signaling. Small, 6, 832-842.

Tucek, J., Machala, L., Ono, S., Namai, A., Yoshikiyo, M., Imoto, K., … Zboril, R. (2015). Zeta-Fe2O3-A new stable polymorph in iron(III) oxide family. Scientific Reports, 5, 15091.

Tuček, J., Zbořil, R., Namai, A., & Ohkoshi, S. (2010). ε-Fe2O3: An advanced nanomaterial exhibiting giant coercive field, millimeter-wave ferromagnetic resonance, and magnetoelectric coupling. Chemistry of Materials, 22, 6483-6505.

Veverka, P., Kaman, O., Kacenka, M., Herynek, V., Veverka, M., Santava, E., … Jirak, Z. (2015). Magnetic La1-xSrxMnO3 nanoparticles as contrast agents for MRI: The parameters affecting H-1 transverse relaxation. Journal of Nanoparticle Research, 17, 33.

Wu, X., Tan, Y., Mao, H., & Zhang, M. (2010). Toxic effects of iron oxide nanoparticles on human umbilical vein endothelial cells. International Journal of Nanomedicine, 5, 385-399.

Xing, J. Z., Zhu, L., Gabos, S., & Xie, L. (2006). Microelectronic cell sensor assay for detection of cytotoxicity and prediction of acute toxicity. Toxicology in vitro, 20, 995-1004.

Xing, Z., Zhu, L., Jackson, J. A., Gabos, S., Sun, X. J., Wang, X. B., & Xu, X. (2005). Dynamic monitoring of cytotoxicity on microelectronic sensors. Chemical Research in Toxicology, 18, 154-161.

Yang, W., Lee, J., Hong, S., Lee, J., Lee, J., & Han, D. W. (2013). Difference between toxicities of iron oxide magnetic nanoparticles with various surface-functional groups against human normal fibroblasts and fibrosarcoma cells. Materials, 6, 4689-4706.

Zhao, D. Y., Feng, J. L., Huo, Q. S., Melosh, N., Fredrickson, G. H., Chmelka, B. F., & Stucky, G. D. (1998). Triblock copolymer syntheses of mesoporous silica with periodic 50 to 300 angstrom pores. Science, 279, 548-552.

Disruption of Cell Adhesion and Cytoskeletal Networks by Thiol-Functionalized Silica-Coated Iron Oxide Nanoparticles