Physics Faculty, University of Duisburg-Essen, Duisburg, Germany.
J Colloid Interface Sci. 2012 Jan 1;365(1):41-5. doi: 10.1016/j.jcis.2011.09.024. Epub 2011 Sep 17.
In this article, a systematic study of the design and development of surface-modification schemes for silica coated nanocomposite via an in situ, one-pot way is presented. Silica coated CdSe/ZnS nanoparticles were prepared in a water-in-oil microemulsion and subsequently surface modified via addition of various organosilane reagents to the microemulsion system. The resulting functionalized composite nanoparticles were characterized by different techniques like Transmission Electron Microscopy (TEM), photoluminescence spectroscopy and zeta-potential measurements. The results demonstrate that depending on the sequence of addition of silica precursors and organosilanes the product can show bright luminescence or considerable colloidal stability. The organosilanes molecules which are used here, act both as a stabilizer of the microemulsion system (regarding the charge compensation) and as a functional group the final product on top of silica shell. Using these surface-modification process, silica coated nanoparticles can be more readily conjugated with biomolecules and used as highly luminescent, sensitive, and reproducible labels in bioanalytical applications. Most importantly such surface functionalization could pave the way for controlled multi-mixed nanoparticles encapsulation (for example magnetic and QD nanoparticles).
本文通过原位一锅法对二氧化硅包覆纳米复合材料的表面修饰方案进行了系统研究。在油包水微乳液中制备了二氧化硅包覆的 CdSe/ZnS 纳米粒子，然后通过向微乳液体系中添加各种有机硅烷试剂对其进行表面修饰。通过透射电子显微镜（TEM）、光致发光光谱和 zeta 电位测量等不同技术对所得功能化复合纳米粒子进行了表征。结果表明，根据二氧化硅前体和有机硅烷的添加顺序，产物可以表现出明亮的发光或相当的胶体稳定性。这里使用的有机硅烷分子不仅可以作为微乳液体系的稳定剂（关于电荷补偿），而且还可以作为功能基团，最终在二氧化硅壳层上得到产物。通过使用这种表面修饰工艺，可以更方便地将二氧化硅包覆的纳米粒子与生物分子偶联，并在生物分析应用中用作高发光、高灵敏度和可重现的标记物。最重要的是，这种表面功能化可以为控制多混合纳米粒子封装（例如磁性和 QD 纳米粒子）铺平道路。
