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

Manganese zinc ferrite nanoparticles (MZF NPs) were synthesized by using an 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 XRD, ICP-OES, FTIR, TEM, VSM and DLS methods. Mean particle size of bare MZF NPs was around 14 nm. Chitosan coated NPs showed hydrodynamic size of 300 nm. The chitosan coated MZF NPs exhibited a positive surface charge across a wide pH range. All samples showed superparamagnetic-like behavior (zero remanence and coercivity) at room temperature. Furthermore, they were evaluated for imaging by measuring the relaxivities (r(1) and r(2)). Chitosan encapsulated MZF NPs exhibited larger MRI contrast effects than that of commercial samples showing high potential to be applied as a MRI contrast agent. 2015 JNS All rights reserved