Photoactivation of CdSe/ZnS quantum dots embedded in silica colloids

被引：71

作者：

Dembski, Sofia ^{[4
]}

Graf, Christina ^{[1
]}

Krueger, Tim ^{[2
]}

Gbureck, Uwe ^{[3
]}

Ewald, Andrea ^{[3
]}

Bock, Anne

Ruehl, Eckart ^{[1
]}

机构：

[1] Free Univ Berlin, Inst Chem & Biochem, D-14195 Berlin, Germany

[2] Univ Wurzburg, Lehrstuhl Zell & Entwicklungsbiol, Biozentrum, D-97074 Wurzburg, Germany

[3] Abt & Lehrstuhl Funktionswerkstoffe Med & Zahnhei, D-97070 Wurzburg, Germany

[4] Univ Wurzburg, Lehrstuhl Phys Chem 1, D-97074 Wurzburg, Germany

来源：

SMALL | 2008年 / 4卷 / 09期

关键词：

multicore particles; photoactivation; photoluminescence; quantum dots; silica;

D O I：

10.1002/smll.200700997

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

A study of the influence of the local environment on the light-induced luminescence enhancement of CdSe/ZnS quantum dots (QD) embedded in silica colloids that are dispersed in various solvents is presented. The photoluminescence of the embedded QD is enhanced up to a factor of ten upon photoactivation by ultraviolet or visible light. This enhancement is strongly dependent on the local environment. The thickness-dependent permeability of the silica shell covering the QD controls the influence of the solvent on the QD. If foreign ions are present the activation state is stabilized after termination of the activation, whereas in their absence the process is partially reversible. A new qualitative model for the photoactivation of QD in various environments is developed. It comprises light-induced passivation and subsequent oxidation processes. The embedded QD also retain their fluorescence quantum yield inside living cells. Moreover, they can be activated for many hours in living cells by laser radiation in the visible regime.

引用

页码：1516 / 1526

页数：11

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