Impact of calcination temperature on the spin–spin relaxation time (T2) of MgFe2O4 nanoparticles (in vitro)

Abstract

MgFe2O4 nanoparticles were prepared by the sol–gel method at calcination temperatures of 300 and 500 °C. Then, the effect of calcination temperature on their structural, magnetic, and cytotoxic properties was investigated. In this regard, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy (FTIR) techniques were used to study structural features, vibrating sample magnetometry (VSM) and electron paramagnetic resonance spectroscopy (EPR) methods were used to evaluate the magnetic properties, and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was used to evaluate the cytotoxicity. XRD and FESEM results showed that the particle size should increase with increasing calcination temperature. FTIR spectra indicated the presence of absorption bands in the range 390–560 cm−1 at both calcination temperatures, which is a common feature of spinel ferrite. Also, the VSM analysis showed that the superparamagnetic property decreases with increasing calcination temperature. Spin–spin relaxation time ( T2) was evaluated as one of the important parameters in increasing the quality of magnetic resonance imaging scans by EPR. EPR results showed that the T2 increases with increasing calcination temperature. The cytotoxic effects (MTT test) of MgFe2O4 nanoparticles at different concentrations on normal human fibroblast cells (HU-02) showed dose-dependent cell death. This study showed that lowering the calcination temperature can improve the spin–spin contrast ( T2).