基于能量转移机制的正、负功能团相互作用

Interaction between positive and negative functional groups based on the energy transfer mechanism

制备了一定尺寸的量子点和金纳米粒子,在量子点和金纳米粒子表面修饰具有相同碳原子数,不同正、负电性的功能配体,研究了配体间电性作用和位阻效应对"量子点-金纳米粒子"体系荧光共振能量传递(FRET)过程的影响。采用透射电镜和紫外、荧光等方法对量子点和金纳米粒子的尺寸、形态及光学性质进行表征,并深入研究了末端的正、负电性功能团对FRET效率的影响。结果表明:强的电性作用有利于提高体系FRET的效率,而位阻效应则降低该效率。

Size-fixed quantum dots （QDs） and Au nanoparticles （AuNPs） have been prepared with their surface modified by functional ligands which have the same number of carbon atoms with different terminal functional groups charged positively and negatively. The elec- trostatic interaction and the effect on the FRET process between QDs and AuNPs have been discussed. Transmission electron microscopy, UV and fluorescence spectrophotometer were employed to characterize the morphology of particles and their optical properties. The static and steric effects on the FRET efficiency between QDs and AuNPs were also studied. The results showed that the strong static effect between terminally modified functional groups improves the FRET efficiency, while the strong steric effect weakens it.