Gold-coated iron oxide nanoparticles are a class of potential theranostic nanoparticles that have been studied for their multitude of magnetic and optical properties with possible medical applications. In this work, spherical Au@Fe₃O₄ nanoparticles were successfully synthesized from Fe electrodes immersed in HAuCl₄ solution using a very simple method - pulsed plasma in liquid, without any dopants or special conditions for stabilization. Vibrating sample magnetometer indicated ferromagnetic behavior of the particles at room temperature with coercivity and saturation magnetization of Hc=175 and Ms= 3.56 emu/g, respectively. Face-centered cubic Au and spinel inverse structure of FCC- Fe₃O₄ were determined by X-Ray diffraction analysis. High-resolution transmission electron microscopic analysis revealed that Fe₃O₄ particles with 14 nm in size are connected to 18 nm Au particles. The cytotoxicity of the nanoparticles was evaluated using a XTT assay on Hela cells, revealing very low (cell viability: 98-89% with Fe₃O₄ and 99-91% for Au@Fe₃O₄ NPs). This indicates that Au improves biocompatibility of magnetic nanoparticles, enabling their application in biomedicine

doi.org/10.32737/0005-2531-2023-3-98-104