Synthesis and characterization of monophasic MnFe2O4 nanoparticles for potential application in magnetic hyperthermia

Abstract

Nanostructured materials are being used in a wide range of technological applications. In biomedical applications, magnetic hyperthermia (MH) is a therapeutic modality for the treatment of solid tumors. The materials needed for MH face challenges such as size homogeneity, reasonable temperature increase and biocompatibility. In this work, MnFe2O4 magnetic nanoparticles (Nps) were synthesized by a simple method using the bio-polymer chitosan. Samples with several particles sizes were obtained by treatments at the temperatures of 300, 400, 500 and 600 °C. The particle sizes ranged from 7.8 to 13.3 nm. At 300 K, the saturation magnetization of the Nps varied from 16.2 to 35.8 emu/g. The Mössbauer spectra at low temperatures showed the presence of monophasic MnFe2O4. For all samples, the Mössbauer results at 300 K suggest that the samples are in the superparamagnetic regime. The measurements to obtain the Specific Loss Power (SLP) were conducted at a frequency of 74 kHz and AC field amplitude of 247 Oe. The sample thermally treated at 600 °C and the dispersion prepared with a concentration of 1.0 mg/mL showed the highest SLP of 129.1 W/g.