Department of Materials Physics, Zhejiang Normal University, Jinhua, Zhejiang, People's Republic of China.
Nanotechnology. 2010 Mar 26;21(12):125602. doi: 10.1088/0957-4484/21/12/125602. Epub 2010 Feb 25.
Rational combination of different functional lanthanide materials within a single nanocrystal presents a feasible way to develop a multifunctional nanoplatform for various biomedical applications. The conventional methods of synthesizing and integrating two kinds of material together generally involve laborious procedures, whilst codoping different functional ions inside a single lanthanide nanocrystal usually results in a decrease in both its fluorescence and its magnetic resonance relaxivity. Here, we present a seed-mediated synthetic route to prepare core-shell structured NaY F(4):Y b, Er/NaGdF(4) nanocrystals. Epitaxial growth of a gadolinium layer on an upconversion lanthanide seed not only improves its upconversion fluorescence, but also creates a paramagnetic shell with high magnetic resonance relaxivity. The prepared nanocrystals are uniform in size, stable in water and easy for conjugation after modification, which may have the potential to serve as a versatile imaging tool for smart detection or diagnosis in future biomedical engineering.
在单个纳米晶体内合理组合不同功能的镧系材料为各种生物医学应用开发多功能纳米平台提供了一种可行的方法。将两种材料合成和集成在一起的传统方法通常涉及繁琐的程序，而在单个镧系纳米晶体内共掺杂不同功能的离子通常会导致其荧光和磁共振弛豫率同时降低。在这里，我们提出了一种种子介导的合成方法来制备核壳结构的 NaYF(4):Yb,Er/NaGdF(4)纳米晶。在镧系上转换种子上外延生长一层钆不仅可以提高其上转换荧光，还可以形成具有高磁共振弛豫率的顺磁壳。所制备的纳米晶尺寸均匀，在水中稳定，修饰后易于偶联，有望成为未来生物医学工程中智能检测或诊断的通用成像工具。
