Dong Chaoqing, Huang Xiangyi, Ren Jicun
School of Chemistry and Chemical Technology, Shanghai Jiao Tong University, 800 Dongchuan Rd., Shanghai 200240, PR China.
Ann N Y Acad Sci. 2008;1130:253-61. doi: 10.1196/annals.1430.029.
Quantum dots (QDs) are nanoscale inorganic particles generally composed of II-VI and III-V elements. Recently, QDs have received great interest in biological applications because of their unique and fascinating optical properties. In this short review, we introduce the synthesis of luminescent QDs in the aqueous phase and characterize certain fundamental parameters of luminescent QDs synthesized in the aqueous phase by fluorescence correlation spectroscopy (FCS), which include, for example, their dynamic diameters and surface charges. Meanwhile, combining with some ensemble spectroscopy techniques, we applied FCS to investigate the quenching process and mechanism of heavy metal ions (e.g., Ag(+)) on CdTe QDs, as well as the aggregation and subsequent photoactivation process of 3-mercaptopropionic acid-capping CdTe QDs induced by laser irradiation. Our preliminary results demonstrate that FCS is a sensitive and efficient tool to characterize fluorescent nanoparticles, such as QDs, at the single-molecule detection level.
量子点（QDs）是通常由II-VI族和III-V族元素组成的纳米级无机颗粒。近年来，量子点因其独特而迷人的光学性质而在生物应用中备受关注。在这篇简短的综述中，我们介绍了水相中发光量子点的合成，并通过荧光相关光谱（FCS）表征了水相中合成的发光量子点的某些基本参数，例如它们的动态直径和表面电荷。同时，结合一些整体光谱技术，我们应用FCS研究了重金属离子（如Ag(+)）对CdTe量子点的猝灭过程和机制，以及激光照射诱导的3-巯基丙酸封端的CdTe量子点的聚集和随后的光活化过程。我们的初步结果表明，FCS是在单分子检测水平上表征荧光纳米颗粒（如量子点）的灵敏且有效的工具。
