Ca-Doped MgFe₂O₄ Nanoparticles for Magnetic Hyperthermia and Their Cytotoxicity in Normal and Cancer Cell Lines

Localized magnetic hyperthermia (LMHT) cancer therapy is a much-anticipated technique along with immunotherapy. LMHT can be used as an independent or adjunct therapy to increase the efficacy of radiation and chemotherapy. The superparamagnetic nanoparticles (SPNPs) create LMHT by the electron magnetic spin relaxation (EMR) mechanism in nanocolloids. Magnetic nanoparticles of MgFe2O4 doped with different concentrations of Ca2+ ions were designed to find specific heating efficiency in magnetic hyperthermia (MHT) for applications in cancer therapy. Ca2+-substituted MgFe2O4 (CaxMg1–xFe2O4, x = 0.1, 0.3, and 0.5) nanoparticles with cubic spinel shapes and significant sizes were synthesized using high boiling point organic solvents. The heating efficiency or specific loss power (SLP) was determined using a calorimetric method under various amplitudes of the magnetic field. The best shape with a particular size range for nanoparticles dispersed in deionized (DI) water carriers producing the optimum heating efficiency was specified. The CaxMg1–xFe2O4 (x = 0.1, 0.3, and 0.5) nanoparticles were investigated for in vitrocytotoxicity in normal cells (the mouse muscle fibroblast cell line BLO-11 and the mouse embryonic fibroblast cell line NIH 3T3) and human cancer cells (breast cancer cell line MDA-MB-23 and prostate cancer cell line PC-3) in terms of cell viability. The excellent heating efficiency and biocompatibility along with the lack of cell cytotoxicity of Ca2+-substituted MgFe2O4 nanoparticles were observed. These outcomes propose that MgFe2O4 nanoparticles doped with Ca2+ ions are appropriate for biomedical applications, especially for MHT cancer therapy.