一种制备水溶性的单分散四氧化三铁纳米颗粒的简单但是有效的方法在本文中被介绍. 单分散的Fe3O4纳米颗粒首先通过油酸铁的热分解来合成；然后在三乙胺存在的前提下，依次在氯仿和乙醇中用二巯基丁二酸（DMSA）对得到的油酸包裹的Fe3O4纳米颗粒进行表面二次修饰；最后得到的Fe3O4纳米颗粒被转移至水相中形成稳定的磁流体。TEM照片显示水溶性的Fe3O4纳米颗粒保持单分散性，甚至形成了规则排列的单层。稳定性测验的结果表明通过表面修饰得到的Fe3O4纳米颗粒表水和生理环境体系能够保持稳定性。
A simple, but efficient method for preparation of water-soluble iron oxide nanoparticles has been developed. Monodisperse Fe3O4 nanoparticles were synthesized by thermal decomposition of iron-oleate. Surface double-exchange of oleic acid capped monodisperse Fe3O4 nanoparticles with a familiar 2, 3-dimercaptosuccinnic acid (HOOC-CH(SH)-CH(SH)-COOH, DMSA) was firstly performed in chloroform in the presence of triethylamine, and then this process was repeated in ethanol under the same conditions. The resulting Fe3O4 nanoparticles could be transferred into water to form stable magnetic fluid without post-treatment processes such as filtration and re-concentration. TEM images show that water-soluble Fe3O4 nanoparticles remain monodisperse and even form a monolayer of ordered assembly. Stability assays show that Fe3O4 nanoparticles modified by DMSA via surface double-exchange keep stable in water and other physiological environments.
Figure: DMSA修饰的单分散Fe3O4纳米颗粒的透射电镜图和结构示意图
Referrence:
Z.P. Chen, Y. Zhang, S. Zhang, J.G. Xia, J.W. Liu, K. Xu and N. Gu http://dx.doi.org/10.1016/j.colsurfa.2007.09.017
