Fe3O4 magnetic nanoparticles (MNPs) have received a great deal of attention in biomedical applications due to their high magnetic sensitivity, large surface area, and superparamagnetic behavior. Their low stability, toxicity, and severe accumulation tendency in aqueous media have, however, hindered their application in hyperthermia treatments. This problem can be resolved by the incorporation of non-magnetic and biocompatible shells on Fe3O4. The aim of this research is thus the introduction of glycerin and aluminum oxide (Al2O3) as two proper materials for coating Fe3O4 and the investigation of their efficiency in this field. The results indicated that Glycerin@Fe3O4 and Al2O3@Fe3O4 have a core@shell structure and superparamagnetic features with relatively high saturation magnetization (MS). The cytotoxicity of the synthesized nanoparticles was evaluated on normal fibroblast and lung cancer cell lines (A54912) for 24, 48, and 72 h using the MTT assay. The viability of the A54912 and fibroblast cell lines in the presence of Fe3O4 was significantly lower than the two coated nanoparticles. This implies that the glycerin and Al2O3 provided the Fe3O4 nanoparticles with proper cytocompatibility. The effectiveness of the synthesized NPs in magnetic hyperthermia was evaluated by exposure of the nanoparticle solutions in water (0.2 and 0.4 mg/ml) to a high-frequency alternating magnetic field for 30 min. The results indicated the achievement of treatment temperature (42–46 °C) in a short time and elimination of a large percentage of the A54912 cells. In this regard, the present research reported the promising efficacy and efficiency of Glycerin@Fe3O4 and Al2O3@Fe3O4 in hyperthermia-based cancer treatment.
