Engineered graphene oxide functionalization strategy over MnFe2O4 magnetic nanoparticles toward magnetic inductive heating

Abstract

Magnetic inductive heating of magnetic nanoparticles (MNPs) represents a promising non-invasive therapeutic approach for cancer treatment. In the present study, oxygen-rich graphene oxide has been surface functionalized over superparamagnetic MnFe2O4 (GO@MF1) MNPs prepared through a best-suited sonication-assisted hydrothermal method. The X-ray diffraction has confirmed the formation of phase-pure cubic spinel MnFe2O4 nanoparticles and graphene oxide with an interlayer spacing of 8.21 Å. The GO@MF1 MNPs have exhibited high aqueous colloidal stability with enhanced zeta potential of −40 mV. The static magnetic measurement has confirmed excellent superparamagnetic behavior of GO@MF1 with a saturation magnetization of 56 emu/g and minimized coercivity of 17 Oe. The strong surface functionalization in MnFe2O4 has increased thermal stability of GO@MF1 up to 400°C, and minimized the agglomeration through strong electrostatic repulsion through oxidized graphene. The 2 mg/mL aqueous colloidal solution of GO@MF1 has been utilized for inductive heating experiments at an alternating magnetic field of 12 mT at 585.6 kHz frequency. The choice of magnetic field and frequency has demonstrated remarkable hyperthermia performance, with the GO@MF1 achieving a temperature rise from 28°C to 56.5°C within 600 seconds. The specific absorption rate has reached 330 W/g, while the intrinsic loss power of 6.17 nH·m²·kg⁻¹ has significantly exceeded clinically approved ferrofluids (0.15–3.1 nH·m²·kg⁻¹) and has been comparable to recently reported values.