Mahdiani Mojgan, Rouhani Shohre, Zahedi Payam
Department of Polymer Engineering, Kish International Campus, University of Tehran, Kish Island, Iran.
Department of Organic Colorant, Institute for Color Science and Technology, Tehran, Iran.
J Fluoresc. 2023 Sep;33(5):2003-2014. doi: 10.1007/s10895-023-03197-0. Epub 2023 Mar 25.
A naphthalene diimide dye with two side amine arm was prepared. Uv-Vis and fluorescence spectroscopic techniques are used for their photophysical and solvatochromic characteristics in different solvents. The Lippert-Mataga plot for naphthalene diimide demonstrated a negative linear dependence by increasing polarity. Results showed naphthalene diimide is more polar in the ground than in the excited state. A quenching study was conducted for interacting the naphthalene diimide as a fluorophore and graphene oxide as a quencher. Fluorescence quenching-based platforms in nanoscale have been used in sensing systems. Raman, FTIR, Uv-Vis and fluorescence spectroscopic techniques were used to study the quenching mechanism. The results indicated that graphene plays an effective quencher against the naphthalene diimide, with a quenching efficiency 91%. The Stern-Volmer analysis results show a mix of static and dynamic quenching mechanisms. The binding constant of the quencher-fluorophore and the number of binding sites have been reported. Thermodynamic parameters of their interaction were evaluated. The negative values of the Gibbs free energy confirm that the complexation process is spontaneous. Meanwhile, the positive entropy value confirms that the favorable pathway process.
制备了一种带有两个侧胺臂的萘二亚胺染料。采用紫外-可见光谱和荧光光谱技术研究其在不同溶剂中的光物理和溶剂化显色特性。萘二亚胺的 Lippert-Mataga 图显示，随着极性增加呈负线性相关。结果表明，萘二亚胺在基态比激发态极性更大。进行了一项猝灭研究，以萘二亚胺作为荧光团，氧化石墨烯作为猝灭剂相互作用。基于荧光猝灭的纳米级平台已用于传感系统。采用拉曼光谱、傅里叶变换红外光谱、紫外-可见光谱和荧光光谱技术研究猝灭机制。结果表明，石墨烯对萘二亚胺具有有效的猝灭作用，猝灭效率为91%。Stern-Volmer分析结果表明存在静态和动态猝灭机制的混合。报道了猝灭剂-荧光团的结合常数和结合位点数量。评估了它们相互作用的热力学参数。吉布斯自由能的负值证实络合过程是自发的。同时，正熵值证实了有利的途径过程。
