Synthesis and metal ion-sensing properties of FRET-based fluorescent chemosensors

FRET被定义为两个荧光团之间的激发态能量相互作用，其中激发的供体能量被转移到没有任何光子发射的受体部分。本研究合成了几种新型的基于fret的金属离子荧光化学传感器。例如，在325 nm处激发对应于2-氨基色氨酸-芘衍生物（T2NH-PnP）芘单元的吸收，在600 nm处观察到2-氨基色氨酸单元的发射，表明T2NH-PnP （FRET-on）发生分子内FRET。然而，当将Hg^2+或Cu^2+加入到T2NH-PnP溶液中时，2-氨基色氨酸的荧光显著猝灭，而芘的荧光则恢复（FRET-off）。

FRET is defined as an excited-state energy interaction between two fluorophores in which excited donor energy is transferred to an acceptor part without any photon-emission. In this study, some new FRET-based fluorescent chemosensors for metal ions were synthesized. For example, excited at 325 nm corresponding to the absorption of pyrene unit of 2-aminotryptanthrin-pyrene derivative (T2NH-PnP), emission at 600 nm from 2-aminotryptanthrin unit is observed, indicating that intramolecular FRET occurs in T2NH-PnP (FRET-on). However, when Hg^2+ or Cu^2+ is added to a solution of T2NH-PnP, the fluorescence of 2-aminotryptanthrin is dramatically quenched whereas that of pyrene is revived (FRET-off).