Nanoscale assembly of amine-functionalized colloidal iron oxide

We demonstrate a single-step facile approach for highly water-stable assembly of amine-functionalized Fe3O4 nanoparticles using thermal decomposition of Fe-chloride precursors in ethylene glycol medium in the presence of ethylenediamine. The average size of nanoassemblies is 40 perpendicular to 1 nm, wherein the individual nanoparticles are about 6nm. Amine-functionalized properties are evident from Fourier transform infrared spectrometer (FTIR), thermal and elemental analyses. The saturation magnetization and spin-echo r(2) of the nanoassemblies were measured to be 64.3emu/g and 314.6 mM(-1) s(-1), respectively. The higher value of relaxivity ratio(r(2)/r(1) = 143) indicates that nanoassemblies are a promising high-efficiency T2 contrast agent platform. & 2009 Elsevier B.V. All rights reserved.