Synthesis of Ca2+ substituted cobalt zinc ferrite nanoparticles for magnetic induction hyperthermia

Magnetic induction hyperthermia has great potential in cancer treatment. However, the low heating efficiency of the magnetic nanoparticles (MNPs) with self-regulated temperature capability limits its clinical application. Here, the self-regulated temperature MNPs of Ca-doped Co-Zn ferrite MNPs (Ca x Co 0.5-x Zn 0.5 Fe 2 O 4 , 0 ≤ x ≤ 0.20), with high heating efficiency, were successfully synthesized by co-precipitation method followed by heat treatment. Noticeably, the x = 0.1 suspension sample can self-stabilize the temperature for high-temperature hyperthermia, whereas x = 0.2 suspension sample can self-stabilize the temperature suitable for conventional hyperthermia under an alternating magnetic field of 32 kA/m and 100 kHz. In vitro cell experiments indicate that the MNPs have good biocompatibility. The results demonstrate that optimized saturation magnetization ( σ S ) and tunable Curie temperature (Tc) enhance both the heating efficiency and thermal safety of the nanoparticles during magnetic induction hyperthermia treatment.