Landmark Kevin J, Dimaggio Stassi, Ward Jesse, Kelly Christopher, Vogt Stefan, Hong Seungpyo, Kotlyar Alina, Myc Andrzej, Thomas Thommey P, Penner-Hahn James E, Baker James R, Holl Mark M Banaszak, Orr Bradford G
Programs in Applied Physics, University of Michigan, Ann Arbor, Michigan 48109, USA.
ACS Nano. 2008 Apr;2(4):773-83. doi: 10.1021/nn800034w.
Organic-coated superparamagnetic iron oxide nanoparticles (OC-SPIONs) were synthesized and characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. OC-SPIONs were transferred from organic media into water using poly(amidoamine) dendrimers modified with 6-TAMRA fluorescent dye and folic acid molecules. The saturation magnetization of the resulting dendrimer-coated SPIONs (DC-SPIONs) was determined, using a superconducting quantum interference device, to be 60 emu/g Fe versus 90 emu/g Fe for bulk magnetite. Selective targeting of the DC-SPIONs to KB cancer cells in vitro was demonstrated and quantified using two distinct and complementary imaging modalities: UV-visible and X-ray fluorescence; confocal microscopy confirmed internalization. The results were consistent between the uptake distribution quantified by flow cytometry using 6-TAMRA UV-visible fluorescence intensity and the cellular iron content determined using X-ray fluorescence microscopy.
合成了有机包覆的超顺磁性氧化铁纳米颗粒（OC-SPIONs），并通过透射电子显微镜和X射线光电子能谱对其进行了表征。使用经6-TAMRA荧光染料和叶酸分子修饰的聚（酰胺胺）树枝状大分子，将OC-SPIONs从有机介质转移到水中。使用超导量子干涉装置测定所得树枝状大分子包覆的SPIONs（DC-SPIONs）的饱和磁化强度为60 emu/g Fe，而块状磁铁矿的饱和磁化强度为90 emu/g Fe。使用两种不同且互补的成像方式（紫外可见和X射线荧光）证明并量化了DC-SPIONs在体外对KB癌细胞的选择性靶向作用；共聚焦显微镜证实了其内化过程。通过流式细胞术使用6-TAMRA紫外可见荧光强度定量的摄取分布与使用X射线荧光显微镜测定的细胞铁含量之间的结果是一致的。
