Paramagnetic, silicon quantum dots for magnetic resonance and two-photon imaging of macrophages.
Paramagnetic, silicon quantum dots for magnetic resonance and two-photon imaging of macrophages.
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DOI：
10.1021/ja909303g
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发表时间：
2010-02-17
影响因子：
15
通讯作者：
Louie, Angelique Y.
中科院分区：
文献类型：
--
作者：
Tu, Chuqiao;Ma, Xuchu;Pantazis, Periklis;Kauzlarich, Susan M.;Louie, Angelique Y.
量子点（QD）是一个有吸引力的平台，用于构建多模态成像探针，但典型的镉QD的毒性限制了其临床应用的热情。无毒的硅QD更有前途，但往往需要短波长激发，这会受到组织散射和自发荧光伪影的影响。在这里，我们报告的顺磁性，锰掺杂，硅量子点（（SiMn量子点）的合成，并证明它们是可检测的MRI和近红外激发，双光子成像。SiMn QD用硫酸葡聚糖包被以使它们靶向巨噬细胞上的清道夫受体，这是易损斑块的生物标志物。TEM图像显示，孤立的量子点具有平均核直径为4.3 ± 1.0 nm，通过动态光散射（DLS）测量的包覆纳米颗粒的流体动力学直径范围为8.3至43 nm。SiMn量子点的r1弛豫率为25.50 ± 1.44 mM−1s−1，r2弛豫率为89.01 ± 3.26 mM−1s−1（37 °C，1.4 T）。它们在441 nm处发射强荧光，在水中的量子产率为8.1%。细胞研究表明，探针通过受体介导的过程特异性地在巨噬细胞中积累，对哺乳动物细胞无毒，并在T1加权磁共振和单光子或双光子激发荧光图像中产生明显的对比。这些量子点具有很好的诊断潜力，因为高巨噬细胞密度与易破裂的动脉粥样硬化斑块相关。
Quantum dots (QDs) are an attractive platform for building multimodality imaging probes, but the toxicity for typical cadmium QDs limits enthusiasm for their clinical use. Nontoxic, silicon QDs are more promising but tend to require short wavelength excitations which are subject to tissue scattering and autofluorescence artifacts. Herein, we report the synthesis of paramagnetic, manganese-doped, silicon QDs ((SiMn QDs) and demonstrate that they are detectable by both MRI and near infrared excited, two-photon imaging. The SiMn QDs are coated with dextran sulfate to target them to scavenger receptors on macrophages, a biomarker of vulnerable plaques. TEM images show that isolated QDs have an average core diameter of 4.3 ± 1.0 nm and the hydrodynamic diameters of coated nanoparticles range from 8.3 to 43 nm measured by Dynamic Light Scattering (DLS). The SiMn QDs have an r1 relaxivity of 25.50 ± 1.44 mM−1s−1 and an r2 relaxivity of 89.01 ± 3.26 mM−1s−1 (37 °C, 1.4 T). They emit strong fluorescence at 441 nm with a quantum yield of 8.1% in water. Cell studies show that the probes specifically accumulate in macrophages by a receptor-mediated process, are nontoxic to mammalian cells, and produce distinct contrast in both T1-weighted magnetic resonance and single- or two-photon excitation fluorescence images. These QDs have promising diagnostic potential as high macrophage density is associated with atherosclerotic plaques vulnerable to rupture.
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影响因子：
10.8
作者：
He, Guang S.;Zheng, Qingdong;Prasad, Paras N.
通讯作者：
Prasad, Paras N.
影响因子：
56.9
作者：
Larson, DR;Zipfel, WR;Webb, WW
通讯作者：
Webb, WW
影响因子：
82.9
作者：
Brown, EB;Campbell, RB;Jain, RK
通讯作者：
Jain, RK
影响因子：
3.8
作者：
Kobat, Demirhan;Durst, Michael E.;Xu, Chris
通讯作者：
Xu, Chris
DOI：
10.1039/b913320h
发表时间：
2009-12-14
期刊：
Dalton transactions (Cambridge, England : 2003)
影响因子：
--
作者：
Ma X;Xu F;Atkins TM;Goforth AM;Neiner D;Navrotsky A;Kauzlarich SM
通讯作者：
Kauzlarich SM