Luo Yan-Ling, Fan Li-Hua, Gao Gai-Ling, Chen Ya-Shao, Shao Xiao-Hua
Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China.
J Nanosci Nanotechnol. 2009 Nov;9(11):6439-52. doi: 10.1166/jnn.2009.1306.
A core-shell multilayered composite microsphere with electric and magnetic features was designed and prepared on the basis of mutilayered fabrication. This kind of microspheres was obtained by introducing a rod-like conductive polyanilline (PANI) or its derivatives onto the surface of magnetic Fe3O4 nanoparticles with 4,4'-diphenylmethane diisocyanate as a anchor molecule. Subsequently, the Fe3O4/PANI or Fe3O4/aniline oligomers microspheres, as a secondary core, were covered with a cross-linked shell layer which was constructed by a dispersion polymerization process of methacrylic acid and vinyl pyrrolidone. The structure and morphologies were characterized by using a FTIR, XRD, UV-vis, SEM, TEM and TGA. The average diameter of Fe3O4 nanoparticles prepared is about 10.7 nm, and the PANI nanobars hold the size in the range of about 20.4-25.6 nm. The PANI nanobars are covalently assembled on the surface of Fe3O4 nanoparticles mainly in a mode of extended or horizontal arrangements through XRD and TEM results. The electromagnetic properties were examined based on different polymerization degrees and component ratios of PANI or its derivatives, showing characteristics of soft magnetic materials and controllable conductivity. The multilayer microspheres can be readily used to perform separation and magnetism guide, even electric and pH-modulated drug release in the light of swelling determination and a laser diffraction particle size analyzer, and are potentially of interest for drug targeting purpose.
基于多层制造技术设计并制备了一种具有电磁特性的核壳多层复合微球。这种微球是通过以4,4'-二苯基甲烷二异氰酸酯为锚定分子，将棒状导电聚苯胺（PANI）或其衍生物引入磁性Fe3O4纳米颗粒表面而获得的。随后，以Fe3O4/PANI或Fe3O4/苯胺低聚物微球作为次级核，用甲基丙烯酸和乙烯基吡咯烷酮的分散聚合过程构建的交联壳层进行包覆。通过傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）、紫外可见光谱（UV-vis）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）和热重分析（TGA）对其结构和形貌进行了表征。制备的Fe3O4纳米颗粒的平均直径约为10.7 nm，聚苯胺纳米棒的尺寸在约20.4 - 25.6 nm范围内。根据XRD和TEM结果，聚苯胺纳米棒主要以伸展或水平排列的方式共价组装在Fe3O4纳米颗粒表面。基于聚苯胺或其衍生物的不同聚合度和组分比例对电磁性能进行了研究，结果表明其具有软磁材料的特性和可控的导电性。根据溶胀测定和激光衍射粒度分析仪，这种多层微球可很容易地用于进行分离和磁导向，甚至实现电和pH调节的药物释放，并且在药物靶向方面具有潜在的应用价值。
