Investigating antitumor therapeutic efficacy using magnetic hyperthermia of Fe₃O₄nanoparticles

Four sets of Fe3O4 nanoparticles were synthesized using a one-pot hydrothermal method using ethylene glycol (EG) and water reaction mixture. The EG coated Fe3O4 nanoparticles were characterized using XRD (X-ray diffraction) and DLS (dynamic light scattering). The nanoparticles hydrodynamic sizes are in the range 60-100 nm and showed good dispersibility in water and cellular medium without any aggregation. The specific absorption rate (SAR) under an alternating magnetic field (AMF) was measured to evaluate the magneto hyperthermic effect of the nanoparticles under field amplitudes of 51.85, 43.87, 35.89, and 27.92 kA/m and field frequencies in the range 384.5-167.30 kHz. The nanoparticles synthesized using 30% EG showed the highest SAR value of 372.95 W/g, whereas the particles synthesized using 70% EG showed a SAR value of 217.12 W/g. SAR values show a linear dependency on the AC frequency whereas the field amplitude displayed a nonlinear effect on the SAR. Breast cancer cells (MDA) treated with the nanoparticles for 30 minutes under an AMF of frequency of 384.5 kHz and strength of 24.67 kA/m showed a 50% decrease in cell viability. The cellular viability further decreased to 25% after 24 h treatment under the AMF which is remarkable for the therapeutic application of the nanoparticles. The apoptotic cell death showed a dependency on the AMF frequency and strength combinations.