Department of Innovative and Engineered Materials, Tokyo Institute of Technology , J2-40, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan.
Langmuir. 2011 Mar 15;27(6):2923-8. doi: 10.1021/la1041019. Epub 2011 Feb 3.
The present Article describes the synthesis of ferromagnetic capsules approximately 330 nm in diameter with a nanometer-thick shell to apply to magnetic carriers in a magnetically guided drug delivery system. The magnetic shell of 5 nm in thickness is a nanohybrid, composed of ordered alloy FePt nanoparticles of approximately 3-4 nm in size and a polymer layer of a cationic polyelectrolyte, poly(diaryldimethylammonium chloride) (PDDA). The magnetic capsules have an excellent capacity for carrying medical drugs and genes. Surface-modified silica particles with PDDA were used as a template for the capsules. FePt nanoparticles were deposited on the PDDA-modified silica particles through a polyol method followed by dissolving the silica particles with a NaOH solution, resulting in the formation of the magnetic capsules as the final product. A three-dimensional hollow structure is maintained by the nanohybrid shell. The FePt-nanoparticles/PDDA nanohybrid shell also exhibits a ferromagnetic feature at room temperature because the FePt nanoparticles of an ordered-alloy phase are formed with the aid of PDDA despite the small size (3-4 nm).
本文描述了约 330nm 直径的铁磁胶囊的合成，该胶囊具有纳米级厚度的壳，用于磁导向药物输送系统中的磁性载体。厚度为 5nm 的磁性壳是一种纳米杂化材料，由约 3-4nm 尺寸的有序合金 FePt 纳米颗粒和聚合物层阳离子聚电解质聚（二芳基二甲基氯化铵）（PDDA）组成。这些磁性胶囊具有携带药物和基因的优异能力。使用 PDDA 修饰的二氧化硅颗粒作为胶囊的模板。通过多元醇法将 FePt 纳米颗粒沉积在 PDDA 修饰的二氧化硅颗粒上，然后用 NaOH 溶液溶解二氧化硅颗粒，最终形成磁性胶囊作为最终产物。纳米杂化壳保持了三维空心结构。由于有序相的 FePt 纳米颗粒在 PDDA 的辅助下形成，尽管尺寸较小（3-4nm），FePt 纳米颗粒/PDDA 纳米杂化壳在室温下也表现出铁磁特性。
