Utsumi Shigenori, Urita Koki, Kanoh Hirofumi, Yudasaka Masako, Suenaga Kazutomo, Iijima Sumio, Kaneko Katsumi
Department of Chemistry, Faculty of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan.
J Phys Chem B. 2006 Apr 13;110(14):7165-70. doi: 10.1021/jp0569640.
A single-wall carbon nanohorn (SWNH) colloid was made to be magnetically responsive by anchoring magnetite nanoparticles prepared by the homogeneous mixing of FeCl(2)-FeCl(3) and NaOH solutions. Transmission electron microscopy observation showed the high dispersion of magnetite particles of 2-9 nm on the surface of the SWNH colloid, coinciding with the broad X-ray diffraction peaks of the magnetites. The magnetization measurements showed that the magnetite nanoparticles-anchored SWNH (mag-SWNH) colloid has the hybrid property of ferrimagnetism and superparamagnetism. It was demonstrated that mag-SWNH colloid dispersed in water by sonication responded to an external magnetic field, gathering toward a magnet. N(2) adsorption experiments showed the high nanoporosity of mag-SWNHs and that magnetite nanoparticles were preferably anchored at "nanowindow" sites and the entrance sites of interstitial pores. This magnetically responsive SWNH colloid should contribute to the field of drug delivery.
通过将由FeCl₂ - FeCl₃和NaOH溶液均匀混合制备的磁铁矿纳米颗粒锚定，使单壁碳纳米角（SWNH）胶体具有磁响应性。透射电子显微镜观察显示，2 - 9 nm的磁铁矿颗粒在SWNH胶体表面高度分散，这与磁铁矿的宽X射线衍射峰一致。磁化测量表明，磁铁矿纳米颗粒锚定的SWNH（mag - SWNH）胶体具有亚铁磁性和超顺磁性的混合特性。结果表明，通过超声分散在水中的mag - SWNH胶体对外加磁场有响应，会向磁铁聚集。N₂吸附实验表明mag - SWNH具有高纳米孔隙率，且磁铁矿纳米颗粒优先锚定在“纳米窗口”位点和间隙孔的入口位点。这种磁响应性SWNH胶体应有助于药物递送领域。
