[Preparation and characterization of superparamagnetic iron oxide nanoparticles].
OBJECTIVE
To determine the physical and magnetic properties of superparamagnetic iron oxide (SPIO) nanoparticle prepared in our laboratory and evaluate its possibility for use as contrast agents in magnetic resonance imaging (MRI).


METHODS
The SPIO nanoparticle was obtained by means of classical coprecipitation in dextran solution and its size determined by electron microscopy and photon-correlation spectroscopy. The iron content was determined by phenanthroline photometry, and T(2) values as well as relaxivity evaluated with a clinical MR system at 1.5T.


RESULTS
Dextran-coated magnetite particles with a hydrodynamic diameter of 85.9 nm were prepared. The iron core size was 15 nm and the formation of Fe(3)O(4) crystal in SPIO nanoparticles was confirmed by X-ray diffraction (XRD) analysis. These particles possessed some characteristics of superparamagnetic and show a smaller spin-spin relaxation, with relaxivity and saturation magnetization of 0.1567 mmol(-1)/ms(-1) and 80 emu/g Fe, respectively.


CONCLUSIONS
A stable SPIO nanoparticle with a dextran coating have been developed, and in vitro evaluation of its physical and magnetic properties suggests its potential for use as the contrast agent in MRI.
Liu
Shi-ting
ST
Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. shiting-liu@263.net
Yan
Yuan
Y
Chen
Zhi-liang
ZL
Zhang
Yu-zhong
YZ
Jin
Xing
X
D006801:Humans; D007501:Iron / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry*; D010087:Oxides / Q000138:chemical synthesis / Q000737:chemistry*; D014961:X-Ray Diffraction
D010087:Oxides; C094094:carboxydextran-coated magnetic iron oxide particles; D007501:Iron