Non-polymer Coated Fe{sub}3O{sub}4 Aqueous Dispersion with NH{sub}3 -surface Modification as New Magnetite Nanoparticles and Their Biomedical Applications

摘要

Well-dispersed Fe{sub}3O{sub}4 nanoparticles were synthesized using chemical coprccipitation and the addition of organic acid as adherent in an aqueous solution. The resulting iron oxide particles were manipulated as small as 6 nm diameter in size. The nanoparticlcs exhibit cationic surface mostly decorated with terminal ～(NH{sub}3){sup}+. The in vitro cytotoxicity test revealed excellent biocompatibility to further explore for their potential in vivo applications. NMR measurements showed significantly reduced water proton relaxation times T{sub}1 and T{sub}2. The MR images of the nanoparticlcs in water and serum were then investigated using 1.5T clinical MR imager.