Foderà Vito, Groenning Minna, Vetri Valeria, Librizzi Fabio, Spagnolo Salvatore, Cornett Claus, Olsen Lars, van de Weert Marco, Leone Maurizio
Dipartimento di Scienze Fisiche e Astronomiche, Università degli Studi di Palermo, Palermo, Italy.
J Phys Chem B. 2008 Nov 27;112(47):15174-81. doi: 10.1021/jp805560c.
The fluorescent dye thioflavin T (ThT) is commonly used for in situ amyloid fibril detection. In this work, we focused on the spectroscopic properties and chemical stability of ThT in aqueous solution as a function of pH, temperature, and dye concentration. A reversible hydroxylation process occurs in alkaline solutions, which was characterized using a combination of UV-vis absorption spectroscopy, proton NMR, and density functional theory (DFT). On the basis of these studies, we propose a chemical structure for the hydroxylated form. Finally, by means of fluorescence spectroscopy, ThT hydroxylation effects on in situ amyloid detection have been investigated, providing new insights on the efficiency of the ThT assay for quantitative fibril evaluation at basic pH.
荧光染料硫黄素T（ThT）常用于原位淀粉样纤维检测。在这项工作中，我们重点研究了ThT在水溶液中的光谱性质和化学稳定性随pH值、温度和染料浓度的变化。在碱性溶液中会发生可逆的羟基化过程，我们结合紫外可见吸收光谱、质子核磁共振和密度泛函理论（DFT）对其进行了表征。基于这些研究，我们提出了羟基化形式的化学结构。最后，通过荧光光谱法，研究了ThT羟基化对原位淀粉样检测的影响，为在碱性pH条件下定量纤维评估的ThT检测效率提供了新的见解。
