Synthesis and Characterization of Chitosan Coated Manganese Zinc Ferrite Nanoparticles as MRI Contrast Agents

Manganese zinc ferrite nanoparticles (MZF NPs) were synthesized by using a direct, efficient and environmental friendly hydrothermal method. To improve the colloidal stability of MZF NPs for biomedical applications, NPs were coated with chitosan by ionic gelation technique using sodium tripolyphosphate (TPP) as crosslinker. The synthesized NPs were characterized by X ray diffraction (XRD) analysis, inductively coupled plasma optical emission spectrometry (ICP-OES), fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), vibrating sample magnetometer (VSM) and the dynamic light scattering (DLS) methods. The results confirmed the spinel ferrite phase formation without any calcination process after synthesis. Mean particle size of bare NPs was around 14 nm. Moreover, certain molar ratio of chitosan to TPP was required for encapsulation of NPs in chitosan. Coated NPs showed hydrodynamic size of 300 nm and polydispersity index about 0.3.