Dekaliuk Mariia O, Viagin Oleg, Malyukin Yuriy V, Demchenko Alexander P
Laboratory of Nanobiotechnology, Palladin Institute of Biochemistry, Leontovicha st. 9, Kyiv 01030, Ukraine.
Phys Chem Chem Phys. 2014 Aug 14;16(30):16075-84. doi: 10.1039/c4cp00138a.
Despite many efforts, the mechanisms of light absorption and emission of small fluorescent carbon nanoparticles (C-dots) are still unresolved and are a subject of active discussion. In this work we address the question as to whether the fluorescence is a collective property of these nanoparticles or they are composed of assembled individual emitters. Selecting three types of C-dots with "violet", "blue" and "green" emissions and performing a detailed study of fluorescence intensity, lifetime and time-resolved anisotropy as a function of excitation and emission wavelengths together with the effect of viscogen and dynamic fluorescence quencher, we demonstrate that the C-dots represent assemblies of surface-exposed fluorophores. They behave as individual emitters, display electronic anisotropy, do not exchange their excited-state energies via homo-FRET and possibly display sub-nanosecond intra-particle mobility.
尽管付出了诸多努力，但小型荧光碳纳米颗粒（碳点）的光吸收和发射机制仍未得到解决，仍是一个活跃的讨论话题。在这项工作中，我们探讨了荧光是这些纳米颗粒的集体性质，还是由组装的单个发光体组成的问题。选择三种具有“紫色”、“蓝色”和“绿色”发射的碳点，并详细研究荧光强度、寿命和时间分辨各向异性随激发和发射波长的变化以及粘滞剂和动态荧光猝灭剂的影响，我们证明碳点代表表面暴露荧光团的聚集体。它们表现为单个发光体，显示电子各向异性，不通过同型荧光共振能量转移交换激发态能量，并且可能显示亚纳秒级的颗粒内迁移率。
