Preparation and analysis of Mn1-xZnxFe2O4 nanoparticles coated with chitosan for use as a heating agent and MRI contrast agent in biomedical applications

Abstract

Nanoferrites, day by day become the center of attraction due to their acceptability as contrast agents due to their enhanced properties. Wet chemical coprecipitation was used to prepare Mn1-xZnxFe2O4 nanoparticles. In order to apply the material for biomedical applications, the nanoferrites were also coated with the biodegradable material chitosan. XRD spectra confirmed the spinel ferrite configuration. It also showed that the structure was face centered cubic. TEM and HRTEM images in both bright- and dark- fields were used to analyze the surface structure and particle size. The particle size was observed below 10 nm. From EDS analysis, the elemental composition of the as-dried and coated materials was determined. No impurity was observed in the material. Along with XRD, FTIR also confirmed the formation of bare and coated spinel ferrites. Two characteristic bands were observed for the material that is also the basic features of the ferrite material. Using an M−H diagram, the variation in saturation magnetization and coercivity as a function of zinc content in the coating was investigated in great depth. It was observed that the saturation magnetization vary a little for coating material. The polydispersity index (PDI) and hydrodynamic diameter of the chitosan-coated solution were determined at 2 mg/ml and 4 mg/ml concentrations. It was seen that Mn0.8Zn0.2Fe2O4 and Mn0.6Zn0.4Fe2O4 at both concentrations were exhibit PDI value within the permissible range. It was discovered through an in-vitro cytotoxicity test on HeLa cancer cells that all of the coated samples were nontoxic to use. Relaxivity values were calculated using MRI images. The relaxivities progressively decreased in value as the zinc ions rose. TOF tests were used to examine the effect of the contrast agent. The samples’ heating profiles were examined to determine whether coated nanoferrites were suitable for use in applications involving hyperthermia. It has been noted that the Mn0.6Zn0.4Fe2O4 sample is appropriate for biomedical applications involving hyperthermia.