摘要
Abstract
Fe3O4nanoparticles in oil phase was prepared by a high temperature solvent thermal decomposition method,and surface functional modification of the prepared Fe3O4nanoparticles was carried out by controlling the particle size,the morphology and the like with polyethyleneimine(PEI) and fluorescein isothiocyanate(FITC),thereby providing theoretical basis for application of the Fe3O4 nanoparticles in in-vivo magnetic resonance imaging. The relaxation,stability and biocompatibility of the Fe3O4nanoparticles were characterized by such methods as TEM,XRD,FTIR,TG,VSM,etc. The experimental results showed that,4 nm Fe3O4nanoparticles in oil phase were spherical with narrow size distribution,good monodispersity,cubic spinel structure and superparamagnetic property;after being successfully modified with the PEI and the FITC,the Fe3O4nanoparticles were increased in hydrodynamic diameter,narrow in size distribution and present in aqueous phase stably and uniformly with reduced saturation magnetization,but still had the superparamagnetic property with good fluorescent stability;the Fe3O4-PEI-FITC magnetic fluorescent nanoparticles had good cell biocompatibility,had the longitudinal relaxation rate and the transverse relaxation rate being 7.96 m/ms and 25.83 m/ms,respectively,and thus could be used as T1contrast agent.关键词
纳米颗粒/表面修饰/磁化强度/造影剂/弛豫率Key words
nanoparticles/surface modification/magnetization/contrast agent/relaxation rate分类
化学化工
