Síntese e caracterização de magnetita recoberta por maltodextrina com potencial para aplicação em hipertermia magnética

Abstract

Ferrites, especially magnetite (Fe3O4), have been studied in several applications. Among the proposed applications is nanomedicine, which may be used to treat cancer via magnetic hyperthermia. Magnetic hyperthermia treatment employs magnetic nanoparticles that are applied to patients to accumulate in tumor tissue and, through the application of an alternating magnetic field, they are heated to a therapeutic temperature, where only cancer cells suffer damage or cell death. In this context, the main objective of this work is the synthesis, through the coprecipitation method, of Fe3O4 nanoparticles and coating them with maltodextrin through a complete factorial design (23), with the input variables being the concentration of iron precursors and the amount of maltodextrin, and output variables, the specific absorption rate, mean crystallite diameter and saturation magnetization. All samples of the experimental design were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, hydrodynamic size by dynamic light scattering analysis, scanning electron microscopy with energy dispersive spectroscopy, magnetic measurements, electron paramagnetic resonance and magnetic hyperthermia. Samples containing the same concentration of iron precursor and the different amount of maltodextrin were selected and analyzed to determine the zeta potential. The methodology allowed obtaining magnetite nanoparticles coated with maltodextrin with superparamagnetic characteristics, with an average crystallite diameter of less than 12.5 nm, with high dispersion of sizes and agglomerations, which were confirmed by the characterizations carried out. The results of the statistical analyzes through the correlation matrix analysis showed that the mean crystallite diameter and the saturation magnetization are significant when they are correlated with the input variables. For the average crystallite diameter, the iron precursors have a significant effect, with an increase in the iron precursor there is an increase in the average crystallite diameter. The best experimental set for saturation magnetization is composed of a higher amount of iron precursors and a lower amount of maltodextrin, which was expected and is in line with the literature.