Institute of Physical Chemistry, Demokritos National Research Center, Athens, Greece.
Nanotechnology. 2011 Sep 2;22(35):355602. doi: 10.1088/0957-4484/22/35/355602. Epub 2011 Aug 5.
Open-ended, multi-wall carbon nanotubes (CNTs) with magnetic nanoparticles encapsulated within their graphitic walls (magCNTs) were fabricated by a combined action of templated growth and a ferrofluid catalyst/carbon precursor, and tested as drug hosts. The hybrid nanotubes are stable under extreme pH conditions due to particle protection provided by the graphitic shell. The magCNTs are promising for high capacity drug loading given that the magnetic functionalization did not block any of the active sites available for drug attachment, either from the CNT internal void or on the internal and external surfaces. This is in contrast to typical approaches of loading CNTs with particles that proceed through surface attachment or capillary filling of the tube interior. Additionally, the CNTs exhibit enhanced hydrophilic character, as shown by water adsorption measurements, which make them suitable for biological applications. The morphological and structural characteristics of the hybrid CNTs are evaluated in conjunction to their magnetic properties and ability for drug loading (diaminophenothiazine). The fact that the magnetic functionality is provided from 'inside the walls' can allow for multimode functionalization of the graphitic surfaces and makes the magCNTs promising for targeted therapeutic applications.
无定形多壁碳纳米管（CNTs）内部被磁性纳米粒子包裹（magCNTs），通过模板生长和铁磁流体催化剂/碳前体的共同作用制备，并作为药物载体进行了测试。由于石墨壳提供的颗粒保护，混合纳米管在极端 pH 条件下稳定。鉴于磁性功能化没有阻止任何用于药物附着的活性位点，无论是来自 CNT 内部空隙还是内部和外部表面，magCNTs 有望实现高容量药物负载。这与通过表面附着或管内毛细填充来加载 CNT 颗粒的典型方法形成对比。此外，如通过水吸附测量所示，CNTs 表现出增强的亲水性，这使它们适用于生物应用。结合其磁性特性和药物负载能力（二氨基吩噻嗪）评估了混合 CNTs 的形态和结构特征。磁性功能来自“壁内”的事实可以允许对石墨表面进行多模式功能化，并且使 magCNTs 有望用于靶向治疗应用。
