Yttrium-Doped Iron Oxide Nanoparticles for Magnetic Hyperthermia Applications

Magnetic nanoparticles of Fe₃O₄ doped by different amounts of Y³⁺ (0, 0.1, 1, and 10%) ions were designed to obtain maximum heating efficiency in magnetic hyperthermia for cancer treatment. Single-phase formation was evident by X-ray diffraction measurements. An improved magnetization value was obtained for the Fe₃O₄ sample with 1% Y³⁺ doping. The specific absorption rate (SAR) and intrinsic loss of power (ILP) values for prepared colloids were obtained in water. The best results were estimated for Fe₃O₄ with 0.1% Y³⁺ ions (SAR = 194 W/g and ILP = 1.85 nHm²/kg for a magnetic field of 16 kA/m with the frequency of 413 kHz). The excellent biocompatibility with low cell cytotoxicity of Fe₃O₄:Y nanoparticles was observed. Immediately after magnetic hyperthermia treatment with Fe₃O₄:0.1%Y, a decrease in 4T1 cells' viability was observed (77% for 35 μg/mL and 68% for 100 μg/mL). These results suggest that nanoparticles of Fe₃O₄ doped by Y³⁺ ions are suitable for biomedical applications, especially for hyperthermia treatment.