Optimization of Magnetite Nanoparticles for Magnetic Hyperthermia: Correlation with Physicochemical Properties and Cation Distribution

Abstract

The present study reveals the synthesis of Iron oxide nanoparticles (IONPs) by varying the molar ratio of ferric (Fe3+) to ferrous (Fe2+) ions via chemical coprecipitation method for the study of cationic distribution of Fe‐ions and its potential application for magnetic hyperthermia therapy (MHT). X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X‐ray photoelectron spectroscopy (XPS), were used to characterize the physicochemical properties. Several structural parameters were estimated using the Rietveld refinement, resulting in structural modelling verified by magnetic characteristics. A vibrating sample magnetometer (VSM) assessed the magnetic hysteresis loop at room temperature in a field range of ±15 kOe, revealing superparamagnetic behavior for the ratio Fe2+/Fe3+ 1:2. The saturation magnetization (Ms) of IONPs increased with the increasing Fe2+ concentration and attained a maximum value of 60.21 emu g−1 at a molar ratio of 2:1. The potential of the inductive heating capability of IONPs in an alternating current magnetic field (AMF) was studied to treat localized MHT. The changes in magnetic properties and inductive heating properties of IONPs are associated with the cationic distribution of Fe2+ at the tetrahedral (A) and octahedral (B) sites of crystal structure. The variation in cationic properties at the A and B sites may result in varying/tuneable magnetic properties, affecting the overall heating profiles of hyperthermia.