State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Anal Chem. 2012 Jul 17;84(14):5892-7. doi: 10.1021/ac300127s. Epub 2012 Jul 2.
With DNA as a rigid spacer, Ag nanoparticles (NPs) were bridged to CdS quantum dots (QDs) for the stimulation of exciton-plasmon interactions (EPI) in a photoelectrochemical (PEC) system. Due to their natural absorption overlap, the exciton of the QDs and the plasmon of Ag NPs could be induced simultaneously. The EPI resonant nature enabled manipulating photoresponse of the QDs via tuning interparticle distances. Specifically, the photocurrent of the QDs could be greatly attenuated and even be completely damped by the generated EPI. The work opens a different horizon for EPI investigation through an engineered PEC nanosystem, and provides a viable mechanism for new DNA sensing protocol.
以 DNA 作为刚性间隔物，将银纳米粒子 (Ag NPs) 桥接到硫化镉量子点 (CdS QDs) 上，以在光电化学 (PEC) 系统中刺激激子-等离子体相互作用 (EPI)。由于它们的自然吸收重叠，QDs 的激子和 Ag NPs 的等离子体可以同时被诱导。EPI 的共振性质使我们能够通过调节颗粒间距离来操纵 QDs 的光响应。具体来说，通过生成的 EPI 可以大大衰减甚至完全阻尼 QDs 的光电流。这项工作通过工程化的 PEC 纳米系统为 EPI 的研究开辟了一个不同的视野，并为新的 DNA 传感协议提供了可行的机制。
