Role of the Fe3O4 mass ratio in Fe3O4-Fe nanoparticles with the core-shell structure on their anticancer activity in vitro

Introduction. Currently, most of the drugs used in tumor therapy are highly toxic and cause various toxic effects. Therefore, many drug delivery methods are being developed. The use of nanotechnology is one of the most promising methods. The use of magnetic iron oxide nanoparticles as antitumor agents makes it possible to prevent off-target cytotoxicity and other side effects of traditional chemotherapy. The use of nanoparticles is limited by their low efficiency. the Fe3O4/Fe galvanic couple makes it possible to control the release of toxic iron ions and, accordingly, the activity of nanoparticles. Purpose. The aim of this study is to develop new Fe3O4-Fe nanoparticles with a core-shell structure with antitumor activity in vitro. Nanoparticles containing from 5 % to 90 % iron were synthesized, and a systematic study of the structural, textural, charge, morphological, and magnetic properties of nanoparticles, as well as their in vitro activity against the MCF-7 and HeLa tumor lines, was carried out. Methods. Fe3O4-Fe nanoparticles were obtained by electric explosion of an iron wire in a mixture of gases: argon and oxygen. The mass fraction of the components was regulated by varying the ratio of the components of the gas mixture. The physicochemical properties of nanoparticles were studied using X-ray phase analysis, thermal desorption of nitrogen, transmission electron microscopy, and microelectrophoresis. Antitumor activity was studied using the MTT test against HeLa and MCF-7 cell lines. Results. As a result of the electric explosion of an iron wire in an argon + oxygen gas mixture containing oxygen in the range of 1 – 5 vol. %, Fe3O4-Fe NPs with 5 – 90 % wt. Fe3O4, respectively. The study of the physicochemical properties of nanoparticles showed that the zeta potential does not depend on the content of Fe3O4 in NPs and is -30 mV. The change in the specific surface area and the average particle size passes through a maximum at the content of Fe3O4 W=20 %, which can be explained by the mechanism of oxide phase formation during an electric explosion. Using the MTT test, it was found that nanoparticles containing 5 wt. Fe3O4, in the presence of which, at a concentration of 1 mg/ml, the number of living cells decreased to 16 % relative to the control. Conclusion. In this work, we have shown for the first time that Fe3O4-Fe NPS in the concentration range of 50–100 µg/mL can be used as an antitumor agent. The ability to control the magnetic properties of NPs can be used to target a specific area of tumor tissue using an external magnetic field, and the established relationship between the magnetic moment and the activity of NPs in relation to the MCF-7 cell line has great prospects for clinical application.