Institute of Physics and nanoMA (Center for nanostructured Materials and Analytics), University of Technology, 09107 Chemnitz, Germany.
Institute of Experimental Physics I, Leipzig University, D-04103 Leipzig, Germany.
Int J Mol Sci. 2009 Dec 1;10(12):5239-5256. doi: 10.3390/ijms10125239.
Nanoassemblies are formed via self-assembly of ZnS capped CdSe quantum dots (QD) and perylene bisimide (PBI) dyes. Upon assembly formation the QD photoluminescence is quenched, as can be detected both via single particle detection and ensemble experiments in solution. Quenching has been assigned to FRET and NON-FRET processes. Analysis of FRET allows for a distinction between different geometries of the QD dye assemblies. Time-resolved single molecule spectroscopy reveals intrinsic fluctuations of the PBI fluorescence lifetime and spectrum, caused by rearrangement of the phenoxy side groups. The distribution of such molecular conformations and their changed dynamics upon assembly formation are discussed in the scope of FRET efficiency and surface ligand density.
纳米组装体是通过 ZnS 封端的 CdSe 量子点（QD）和苝二酰亚胺（PBI）染料的自组装形成的。在组装形成后，QD 的光致发光被猝灭，可以通过单粒子检测和溶液中的整体实验来检测到。猝灭归因于 FRET 和 NON-FRET 过程。FRET 的分析允许区分 QD 染料组装体的不同几何形状。时间分辨单分子光谱揭示了 PBI 荧光寿命和光谱的固有波动，这是由苯氧基侧基的重排引起的。在 FRET 效率和表面配体密度的范围内，讨论了这种分子构象的分布及其在组装形成过程中的动态变化。
