Ultra-Small Superparamagnetic Iron Oxide Nanoparticles as MRI Contrast Enhancing Agents
Ultrasmall superparamagnetic iron oxide nanoparticles (USPION) as magnetic resonance imaging were synthesized through a sonochemical co-precipitation method with poly (ethyleneimine) (PEI). The size of the USPION was controlled by poly (ethyleneimine) (PEI) contents, ultrasonic exposure time, and Na4OH concentration. The characteristics of PEI-USPION were studied by X-ray diffractometry, magnetic property measurement system, scanning electron microscopy, transmission electron microscopy, and particle size analysis. The PEI-USPION had an average size of 5~10nm with a narrow size distribution, a perfect magnetite crystal structure, and high saturation magnetization.
Alan K.T. Lau, J. Lu, Vijay K. Varadan, F.K. Chang, J.P. Tu and P.M. Lam
M.A. Do et al., "Ultra-Small Superparamagnetic Iron Oxide Nanoparticles as MRI Contrast Enhancing Agents", Advanced Materials Research, Vols. 47-50, pp. 1076-1079, 2008