中文摘要：

采用纳米沉淀法制备了半导体聚合物CN-PPV纳米粒子,并用改进的Stber方法对纳米粒子进行包覆,获得了发光稳定的SiO2/CN-PPV纳米粒子。用动态光散射(DLS)及透射电镜(TEM)方法对粒子尺寸进行了表征,结果表明包覆前的CN-PPV纳米粒子平均粒径约为30 nm,包覆获得SiO2/CN-PPV纳米粒子的平均粒径约为60 nm。通过紫外-可见吸收光谱及荧光光谱对包覆前后纳米粒子的发光性质进行了比较,发现共轭聚合物CN-PPV包覆后的发射光谱与包覆前相比发生了小的蓝移,表明共轭聚合物的分子构型可能发生了微小变化。SiO2包覆可以提高聚合物发光分子的光稳定性,并且提供用于生物分子耦联的表面,这类材料有望在生物医学成像中获得应用。

英文摘要：

Semiconducting polymer CN-PPV nanoparticles(NPs) were prepared by the reprecipitation method and further encapsulated by a facile method.The particle size and the distribution were characterized by dynamic light scattering(DLS) and transmission electron microscopy(TEM).The average diameter is ~30 nm for bare CN-PPV nanopartilces and ~60 nm for encapsulated ones.UV-Vis and fluorescence spectroscopy showed consistent results between CN-PPV and SiO2/CN-PPV nanoparticles.More importantly,silica capsulation improved the photostablility of CN-PPV nanoparticles,and provided reliable surface for covalent conjugation with biomolecules.These photostable nanoprobes are promising for biomedical imaging applications.