A novel colorimetric and fluorometric method based on coumarin as signalling unit was developed for Hg²⁺ recognition and quantification. Initially, the alkyne functionality was incorporated into a coumarin system and the resulting molecule showed higher specificity and sensitivity for Hg²⁺ over other cations in both absorption and emission sensing assays. The Hg²⁺ recognition was detected as visible colour change from colourless to yellow and as fluorescence quenching. The colour change was assigned to the increased intramolecular charge transfer (ICT) in the signalling unit upon Hg²⁺ binding whereas a decline in the fluorescence intensity was ascribed to the heavy atom effect from Hg²⁺. In order to generate a material with high sensing performance level, alkyne-functionalized molecule was hosted into a polymeric material. The resulting functionalized polymer showed higher sensitivity and selectivity for Hg²⁺ over its corresponding coumarin molecule. The investigation of the possible binding modes for Hg²⁺ suggested both alkyne and triazole functionalities as potential binding sites for Hg²⁺. The limit of detection (LOD) and limit of quantification (LOQ) of the proposed method were evaluated and values less than a recommended maximum level of Hg²⁺contaminant in drinking water (2.00 μg/L) were obtained (LOD = 0.44 μg/L and LOQ = 1.33μg/L). The real-life application of the method was investigated using natural water samples containing Hg²⁺ levels equivalent to the maximum tolerable concentration of Hg²⁺ in drinking water. The outcomes suggested that the method could be used in the sensing and determination of Hg²⁺ level of contaminant in the environment.

中文翻译：

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一种用于 Hg2 的新型高选择性比色法和荧光法香豆素化学传感器。

开发了一种基于香豆素作为信号单元的新型比色荧光测定方法用于Hg ²⁺的识别和定量。最初，炔烃功能被纳入香豆素系统，所得分子在吸收和发射传感测定中显示出比其他阳离子更高的 Hg ²⁺特异性和灵敏度。Hg ²⁺识别被检测为从无色到黄色的可见颜色变化和荧光猝灭。颜色变化归因于 Hg ²⁺结合后信号单元中分子内电荷转移 (ICT) 的增加，而荧光强度的下降归因于 Hg ^{2+的重原子效应}. 为了生成具有高传感性能水平的材料，将炔烃功能化分子承载到聚合物材料中。所得功能化聚合物对 Hg ²⁺的灵敏度和选择性高于相应的香豆素分子。^{对 Hg 2+}可能结合模式的研究表明，炔烃和三唑官能团都是 Hg ²⁺的潜在结合位点。对所提出方法的检测限 (LOD) 和定量限 (LOQ) 进行了评估，其值低于建议的最大 Hg ^2+水平获得了饮用水中的污染物 (2.00 μg/L)（LOD = 0.44 μg/L 和 LOQ = 1.33 μg/L）。使用含有相当于饮用水中Hg ²⁺最大耐受浓度的 Hg 2+ 水平的^天然水样研究该方法的实际应用。结果表明，该方法可用于环境中污染物Hg ^{2+水平的传感和测定。}