配体交换法制备水中高分散稳定性的多羧基修饰Fe_3O_4纳米颗粒  

Synthesis of Polycarboxylic Ligand Capped Fe_3O_4 Nanoparticles with Excellent Water-dispersibility via a Ligand-exchange Approach

作　　者：蒋泽权[1] 宋晟[1] 窦红静[1] 孙康[1] 王一鸣[1] 黄超凡[1] 魏振华[1] 曲冠雄[1] 

机构地区：[1]上海交通大学材料科学与工程学院,金属基复合材料国家重点实验室,上海200240

出　　处：《高等学校化学学报》2012年第12期2609-2616,共8页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20904032;21174082);上海交通大学SMC-晨星青年学者奖励计划;上海交通大学金属基复合材料国家重点实验室开放基金;国家大学生创新性实验计划资助

摘　　要：采用油相高温分解法制备了粒径可控且单分散的油溶性Fe3O4磁性纳米粒子(MNPs-OA),并通过配体交换对其表面进行了亲水性修饰,制备了柠檬酸(CA)、N-(三甲氧基硅丙基)乙二胺三乙酸钠(SiCOOH)、丁烷四羧酸(BTCA)和乙二胺四乙酸(EDTA)四钠4种多羧基配体修饰的水溶性Fe3O4磁性纳米粒子(MNPs-CA,MNPs-SiCOOH,MNPs-BTCA和MNPs-EDTA),其中首次选用四羧基配体BTCA和EDTA四钠来修饰Fe3O4磁性纳米粒子(MNPs).对油溶性MNPs和4种水溶性MNPs的形貌、结构、化学组成和磁性能进行了表征,并对4种多羧基配体修饰的水溶性MNPs在水相中的稳定性和分散性进行了表征.结果表明,所得MNPs的平均粒径为15 nm,具有超顺磁性,配体交换后的水溶性MNPs具有良好的亲水性,并在弱酸～碱性很宽的pH范围内具备良好的分散稳定性.此类多羧基修饰的水溶性MNPs可与适当的阳离子聚电解质进行组装,从而得到在磁靶向载体和磁共振造影(MRI)显影中具有良好应用前景的磁性自组装微囊.Abstract Monodispersed magnetic Fe3O4 nanoparticles （MNPs） capped with oleic acid （MNPs-OA） were synthesized through a thermal decomposition method. On this basis, four kinds of water-soluble Fe3O4 nanoparticles （MNPs-CA, MNPs-SiCOOH, MNPs-BTCA and MNPs-EDTA） capped with four different polycarboxylie ligands, i. e. , citric acid（CA）, n-（trimethoxysilylpropyl）ethylene diamine triacetic acid（SiCOOH） trisodium salt, butane tetraearboxylic acid（BTCA） and ethylenediaminetetraacetic acid（EDTA） tetrasodium salt, were prepared via a ligand exchange approach. Among the four ligands, the BTCA and EDTA tetrasodium salt with four carboxy groups were first chosen to cap Fe3O4 nanoparticles. The morphology, structure, chemical composition and magnetic properties of the four water-dispersible MNPs were characterized by transmission electron microscope （ TEM）, X-ray diffractometer （XRD）, vibrating sample magnetometer （ VSM ）, Fourier transform infrared spectrometer（FTIR） and thermal gravimetric analyzer（TGA）. The water-dispersibility and suface potential of four water-soluble MNPs in their aqueous solutions were also characterized by UV-visible spectrophotometer（UV-Vis） and Malvern Zetaszier analyzer, respectively. The results show that the resultant 15 nm Fe3O4 nanoparticles possess narrow size distribution and superparamagnetism. In addition, the polycarboxylic ligand capped MNPs display excellent dispersibility in their aqueous solutions. By the co-assembly of these MNPs and polyelectrolyte, we fabricated magnetic microcapsules. The microcapsules are of great potential in biomedical fields owing to the magnetic responsivity and MRI imaging capability of MNPs.

关 键 词：Fe3O4磁性纳米粒子 热分解 配体交换 水溶性 多羧基配体 

分 类 号：O614[理学—无机化学] O641[理学—化学]