Preparation and Characterization of Super Paramagnetism Iron Oxide Nanoparticles Modified by Dextran

Superparamagnetic iron oxide nanoparticles( SPIONs) were synthesized by high-temperature thermal decomposition of the iron( III) acetylacetonate( Fe( acac)3) in poly( ethylene glycol)( PEG).SPIONs coated with PEG( PEG-SPIONs) were obtained. Then PEG-SPIONs were modified with dextran( Dex). The results of phenol-sulfuric acid method proved that PEG-SPIONs were coated with Dex. TEM image showed that Dex /PEG-SPIONs had a uniform size distribution with a diameter of 8. 7 ± 1. 5 nm;the hydrodynamic size was 33 nm and the zeta potential value was 13 mV. The Dex /PEG-SPIONs was superparamagnetic with saturation magnetization of 21 emu /g. The results of TGA analysis indicate that there were about 42wt% Dex and 30wt% PEG coating on SPIONs. The calculated saturation magnetization of the iron oxide cores of PEG-SPIONs and Dex /PEG-SPIONs was 75 emu /g.