Evolution of Gold and Iron Oxide Nanoparticles in Conjugates with Methotrexate: Synthesis and Anticancer Effects

Alexander Vasil'kov; Anastasiia Voronova; Tsvetelina Batsalova; Dzhemal Moten; Alexander Naumkin; Eleonora Shtykova; Vladimir Volkov; Ivanka Teneva; Balik Dzhambazov

doi:10.3390/ma16083238

Evolution of Gold and Iron Oxide Nanoparticles in Conjugates with Methotrexate: Synthesis and Anticancer Effects

Materials (Basel). 2023 Apr 19;16(8):3238. doi: 10.3390/ma16083238.

Authors

Alexander Vasil'kov¹, Anastasiia Voronova¹, Tsvetelina Batsalova², Dzhemal Moten², Alexander Naumkin¹, Eleonora Shtykova³, Vladimir Volkov³, Ivanka Teneva², Balik Dzhambazov²

Affiliations

¹ A.N. Nesmeyanov Institute of Organoelement Compounds, RAS, 119334 Moscow, Russia.
² Faculty of Biology, Paisii Hilendarski University of Plovdiv, 4000 Plovdiv, Bulgaria.
³ Shubnikov Institute of Crystallography, FSRC "Crystallography and Photonics", RAS, 119333 Moscow, Russia.

Abstract

Au and Fe nanoparticles and their conjugates with the drug methotrexate were obtained by an environmentally safe method of metal-vapor synthesis (MVS). The materials were characterized by transmission and scanning electron microscopy (TEM, SEM), X-ray photoelectron spectroscopy (XPS), and small-angle X-ray scattering using synchrotron radiation (SAXS). The use of acetone as an organic reagent in the MVS makes it possible to obtain Au and Fe particles with an average size of 8.3 and 1.8 nm, respectively, which was established by TEM. It was found that Au, both in the NPs and the composite with methotrexate, was in the Au⁰, Au⁺ and Au³⁺ states. The Au 4f spectra for Au-containing systems are very close. The effect of methotrexate was manifested in a slight decrease in the proportion of the Au⁰ state-from 0.81 to 0.76. In the Fe NPs, the main state is the Fe³⁺ state, and the Fe²⁺ state is also present in a small amount. The analysis of samples by SAXS registered highly heterogeneous populations of metal nanoparticles coexisting with a wide proportion of large aggregates, the number of which increased significantly in the presence of methotrexate. For Au conjugates with methotrexate, a very wide asymmetric fraction with sizes up to 60 nm and a maximum of ~4 nm has been registered. In the case of Fe, the main fraction consists of particles with a radius of 4.6 nm. The main fraction consists of aggregates up to 10 nm. The size of the aggregates varies in the range of 20-50 nm. In the presence of methotrexate, the number of aggregates increases. The cytotoxicity and anticancer activity of the obtained nanomaterials were determined by MTT and NR assays. Fe conjugates with methotrexate showed the highest toxicity against the lung adenocarcinoma cell line and Au nanoparticles loaded with methotrexate affected the human colon adenocarcinoma cell line. Both conjugates displayed lysosome-specific toxicity against the A549 cancer cell line after 120 h of culture. The obtained materials may be promising for the creation of improved agents for cancer treatment.

Keywords: X-ray photoelectron spectroscopy; X-ray small-angle scattering; anticancer drug; drug conjugates; gold nanoparticles; iron oxide nanoparticles; metal-vapor synthesis; methotrexate.

Grants and funding

This work was supported by the Russian Foundation for Basic Research (RFBR), Project No. 20-53-18006, the National Science Foundation of Bulgaria (NSFB), Project No. KP-06-RUSSIA/14, the Ministry of Science and Higher Education of the Russian Federation (Contract No. 075-03-2023-642) and the State Assignment of the Federal Research Center “Crystallography and Photonics” RAS. During the work, the equipment of the INEOS RAS Molecular Composition Research Center was used.