Conformational switching of the pyridine–pyrimidine–pyridine scaffold for ion-controlled FRET
- 作者：Anne Petitjean ; Jean-Marie Lehn
- 关键词：Conformational switch ; FRET ; Naphthalene ; Acridine ; Coordination
- 刊名：Inorganica Chimica Acta
- 出版年：2007
- 期刊代码：40_00201693
- 类别：ch
- 出版时间：15 February 2007
- 卷：360
- 期：3
- 页码：849-856
- 文件大小：466 K
摘要
Fluorescence resonance energy transfer (FRET) has become a major tool for the static and dynamic study of conformational changes in biological systems. We report herein the investigation of a switchable pyridine–pyrimidine–pyridine scaffold as a support to ion-controlled intramolecular FRET. A dissymmetrical switch bearing naphthalene and acridine fluorophores was synthesized and its photophysical behavior studied. In the neutral state where the molecule adopts a U-shape, the emission of the naphthalene is quenched while a strong emission from the acridine fluorophore is observed, consistent with energy transfer between the naphthalene and the acridine units. The emission of the acridine is also enhanced by the pyridine-induced sensitization (excitation at 280 nm). After introduction of a copper(I) cation which switches the conformation to a W-shape, the complex formed shows the emission of both the naphthalene and acridine units when excited at 280 nm, although coordination also leads to a strong quenching of emission.