Composite silica spheres with magnetic and luminescent functionalities
Composite silica spheres with magnetic and luminescent functionalities
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DOI：
10.1002/adfm.200500565
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发表时间：
2006-03-03
影响因子：
19
通讯作者：
Farle, M
中科院分区：
文献类型：
--
作者：
Salgueiriño-Maceira, V;Correa-Duarte, MA;Farle, M
一类新的高度荧光，光稳定，和磁性核/壳纳米粒子在亚微米尺寸范围内已合成从修改Stober方法结合层层（LbL）组装技术。通过两个主要步骤制备发光磁性纳米颗粒。第一步涉及控制添加四乙氧基硅烷到分散体的Fe 3 O 4/γ-Fe 2 O3纳米粒子，从而均匀地纳入到单分散二氧化硅球的核心。第二步涉及聚电解质和发光CdTe量子点到二氧化硅涂覆的磁铁矿/磁赤铁矿颗粒的表面上的LbL组装，其最终覆盖有二氧化硅的外壳。这些球形颗粒具有典型的220 +/- 10 nm的直径和在室温下的1.34 emu g（-1）的饱和磁化强度，并表现出强的激子光致发光。具有这种核/壳结构的纳米颗粒具有额外的益处，即提供了用于将不同功能并入单个纳米颗粒中的稳健平台（外部二氧化硅壳）。
A new class of highly fluorescent, photostable, and magnetic core/shell nanoparticles in the submicrometer size range has been synthesized from a modified Stober method combined with the layer-by-layer (LbL) assembly technique. Luminescent magnetic nanoparticles are prepared via two main steps. The first step involves controlled addition of tetraethoxysilane to a dispersion of Fe3O4/gamma-Fe2O3 nanoparticles, which are thereby homogeneously incorporated as cores into monodisperse silica spheres. The second step involves the LbL assembly of polyelectrolytes and luminescent CdTe quantum dots onto the surfaces of the silica-coated magnetite/maghemite particles, which are finally covered with an outer shell of silica. These spherical particles have a typical diameter of 220 +/- 10 nm and a saturation magnetization of 1.34 emu g(-1) at room temperature, and exhibit strong excitonic photoluminescence. Nanoparticles with such a core/shell architecture have the added benefit of providing a robust platform (the outer silica shell) for incorporating diverse functionalities into a single nanoparticle.