Novel design of near-infrared fluorescent sensors for the detection of Hg2+ in living cells and real water samples.

[Display omitted] • Two novel near-infrared emissive probes were designed and synthesized for mercury ions detection. • CyHg-Cl probe exhibited high photostability, low background fluorescence and biotoxicity. • Mercury ions in living cells and real water samples were successfully monitored. Mercury sensing and imaging in the bio-system is essential for comprehending its toxicity and therapies. Based on the merocyanine scaffold, we designed and synthesized two novel near-infrared (NIR) fluorescent probes for detecting Hg2+. The release of chloro-substituted merocyanine structure on the probe CyHg-Cl enables fluorescence enhancement rapidly by introducing Hg2+. In addition, the probe CyHg-Cl exhibits NIR emission and a low detection limit of 0.59 µM. Finally, the probe CyHg-Cl was used to detect Hg2+ in live cells and real water samples. [ABSTRACT FROM AUTHOR]