As one of the most toxic metals, Mercury ions cause serious environmental pollution and threaten the health of living organisms. Hence, we designed and synthesised a new near-infrared (NIR) ratiometric fluorescent probe toward monitoring of Hg²⁺ based on quinoline-fused rhodamine dye. Owing to the specific spirolactam ring-opening reaction, the probe exhibits a ratiometric fluorescent change after treatment of Hg²⁺ with increased emission in NIR and significantly reduced emission in visible region. The specific response mechanism and dual-channel fluorescence change allow the probe to have remarkable detection selectivity, fast response and high detection sensitivity. Moreover, with the properties of excellent cell permeability and low cytotoxicity, probe can be applied as detection tool for mercury ions with dual-channel ratiometric fluorescence imaging in living cell.

Graphical Abstract

中文翻译：

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基于喹啉稠合罗丹明染料的新型 Hg2+ 近红外比率荧光探针

汞离子作为毒性最强的金属之一，造成严重的环境污染，威胁生物体的健康。因此，我们设计并合成了一种基于喹啉融合罗丹明染料的新型近红外（NIR）比率荧光探针，用于监测 Hg ^{2+ 。由于特定的螺内酰胺开环反应，探针在Hg 2+}处理后表现出比率荧光变化，近红外发射增加，可见光区域发射显着减少。特定的响应机制和双通道荧光变化使探针具有显着的检测选择性、快速响应和高检测灵敏度。此外，探针具有良好的细胞通透性和低细胞毒性，可作为活细胞中汞离子双通道比率荧光成像的检测工具。

图形概要