Wilson Robert J, Hu Wei, Fu Cheryl Wong Po, Koh Ai Leen, Gaster Richard S, Earhart Christopher M, Fu Aihua, Heilshorn Sarah C, Sinclair Robert, Wang Shan X
Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305, USA.
J Magn Magn Mater. 2009 May 1;321(10):1452-1458. doi: 10.1016/j.jmmm.2009.02.066.
Optical observations of 100 nm metallic magnetic nanoparticles are used to study their magnetic field induced self assembly. Chains with lengths of tens of microns are observed to form within minutes at nanoparticle concentrations of 10(10) per mL. Chain rotation and magnetophoresis are readily observed, and SEM reveals that long chains are not simple single particle filaments. Similar chains are detected for several 100 nm commercial bio-separation nanoparticles. We demonstrate the staged magnetic condensation of different types of nanoparticles into composite structures and show that magnetic chains bind to immunomagnetically labeled cells, serving as temporary handles which allow novel magnetic cell manipulations.
利用对100纳米金属磁性纳米颗粒的光学观测来研究其磁场诱导的自组装。在每毫升10¹⁰个纳米颗粒的浓度下，观察到在几分钟内形成了长度为几十微米的链。很容易观察到链的旋转和磁泳现象，扫描电子显微镜显示长链不是简单的单颗粒细丝。对于几种100纳米的商业生物分离纳米颗粒也检测到了类似的链。我们展示了不同类型纳米颗粒逐步磁凝聚形成复合结构，并表明磁性链与免疫磁性标记的细胞结合，作为临时手柄，实现了新型的磁性细胞操作。
