Exploring highly sensitive fluorescence probe for mercury ion (Hg) determination is of great importance for environment system. In this work, a ratiometric fluorescence probe using N, S co-doped dots (NS-CDs) and silver nanoclusters (AgNCs) were successful constructed for the determination of Hg. In ratiometric fluorescent sensing system, as AgNCs was added to NS-CDs, fluorescence intensity at 442 nm can be reduced but in the increase of intensity at the 762 nm. Inner filter effect (IFE) was attributed to the mainly mechanism of action between the NS-CDs and AgNCs. Interestingly, the fluorescence of NS-CDs/AgNCs at 442 nm was gradually increase after the addition of Hg, while fluorescence at 762 nm was gradually quenched. Owing to the formation of NS-CDs/AgNCsHg complexes, the NS-CDs/AgNCs led to a significant conformational change of Hg. According to the reverse change of two fluorescence peaks (I/I, a novel NS-CDs/AgNCs probe was designed for specific recognition of Hg with the linear range from 0.1 to 90 μM and a limit detection (LOD) of 0.041 μM. Besides, NS-CDs/AgNCs was successful implemented to detect Hg in the sample water with the good recoveries of 92.90–103.64 % (RSD≤4.62 %). Accordingly, the NS-CDs/AgNCs ratiometric fluorescent probe with simplicity, rapidity and high sensitivity exhibited a huge potentiality in the water environment analysis.

中文翻译：

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基于N、S共掺杂点和银纳米团簇的比例荧光探针，用于灵敏检测Hg2+


探索用于汞离子（Hg）测定的高灵敏度荧光探针对于环境系统具有重要意义。在这项工作中，成功构建了一种使用N、S共掺杂点（NS-CD）和银纳米簇（AgNC）的比例荧光探针，用于汞的测定。在比率荧光传感系统中，当NS-CD中添加AgNCs时，442nm处的荧光强度会降低，但762nm处的荧光强度会增加。内过滤效应（IFE）归因于 NS-CD 和 AgNC 之间的主要作用机制。有趣的是，添加Hg后，NS-CDs/AgNCs在442nm处的荧光逐渐增强，而在762nm处的荧光逐渐猝灭。由于NS-CDs/AgNCsHg复合物的形成，NS-CDs/AgNCs导致了Hg的显着构象变化。根据两个荧光峰(I/I)的反向变化，设计了一种新型NS-CDs/AgNCs探针，用于特异性识别Hg，线性范围为0.1~90μM，检测限(LOD)为0.041μM。 ，NS-CDs/AgNCs成功检测了水样中的Hg，回收率高达92.90-103.64%（RSD≤4.62%），因此NS-CDs/AgNCs比率荧光探针具有简单、快速、灵敏度高的特点。在水环境分析方面展现出巨大的潜力。