This study aims to evaluate the therapeutic potential of targeted Fe₃O₄@Au/FA core-shell nanoparticles as dual sensitizers in enhancing radiotherapy and hyperthermia for C6 glioma cancer cells, minimizing off-target effects. The investigation focuses on the efficacy of this combination therapy in promoting apoptosis and generating reactive oxygen species (ROS).

The Fe₃O₄@Au/FA nanoparticles were synthesized and characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) to confirm their size, zeta potential, and morphology. Fourier-transform infrared spectroscopy (FTIR) was used to analyze the functional groups on the nanoparticle surface. The cytotoxicity of the nanoparticles was assessed through the MTT assay on OLN-93 and C6 glioma cells, and cellular uptake was quantified via inductively coupled plasma optical emission spectrometry (ICP-OES). Ex vivo biocompatibility was evaluated with hemolysis tests and measurements of liver enzymes, urea, and creatinine. Heat generation was monitored during exposure to alternating magnetic fields (AMF) to calculate cumulative equivalent minutes (CEM). The therapeutic effects were evaluated using colony formation assays (CFA) for plating efficiency (PE) and survival fraction (SF) calculation. Flow cytometry was utilized to quantify apoptosis and necrosis, while intracellular ROS levels were measured with the DCFH-DA assay following combined treatments with varying doses of ionizing radiation (0–8 Gy).

Characterization confirmed the nanoparticles’ spherical morphology, with an average size of 40.8 ± 2.8 nm and a negative zeta potential of -19.93 mV. Ex vivo biocompatibility tests demonstrated that the nanoparticles exhibit good compatibility, suggesting minimal adverse effects on biological systems. ICP-OES confirmed effective cellular uptake. CFA revealed significant decreases in PE and SF for combined therapies. Flow cytometry showed enhanced apoptosis and necrosis in combined treatment groups (p < 0.01). Furthermore, ROS levels increased significantly with the maximum radiation dose in the combined treatment (p < 0.0001), highlighting the nanoparticles’ effectiveness in promoting therapeutic responses against glioma cells.

Our magnetic gold core-shell nanoparticles demonstrate good biocompatibility and effective tumor uptake, enhancing radiotherapy and hyperthermia for C6 glioma treatment. These findings highlight their potential for improving treatment outcomes through enhanced apoptosis and ROS generation.