A New Turn-on Naphthalenedimide-Based Chemosensor for Mercury Ions with High Selectivity: Successful Utilization of the Mechanism of Twisted Intramolecular Charge Transfer, Near-IR Fluorescence, and Cell Images

For the first time, a new near-IA turn-on fluorescent chemosensor with high selectivity for Hg2+ ions was designed according to the twisted intramolecular charge transfer (TICT) mechanism. The selective fluorescence enhancement effect can be optimized by modulating the solvent systems. And this naphthalenedimide-based sensor with long wavelength absorption and emission can be used to image intracellular Hg2+ ions in living Hela cells.