Accurate determination of hazardous Hg²⁺ is particularly essential for the environment safety and human health. In this work, using Hg²⁺ as a bridge for the electrochemiluminescence (ECL) reagent and the corresponding coreactant, a new type of self-enhanced ECL nanomaterial was simply and controllably prepared for the first time. In detail, tris (4,4′-dicarboxylicacid-2,2′-bipyridyl) ruthenium(II) dichloride modified with DNA1 (Ru-DNA1) and graphite-like carbon nitride quantum dots linked with DNA2 (QDs-DNA2) were used as the ECL reagent and coreactant, respectively. In the presence of Hg²⁺, they could be integrated together to form a self-enhanced ECL nanomaterial (Ru-DNA1-Hg²⁺-QDs-DNA2) via the T-Hg²⁺-T duplex structure. The ECL signal strength was positively proportional to the concentration of Hg²⁺. On this basis, sensitive and selective detection of Hg²⁺ could be achieved by simply modifying the ECL nanomaterial on the electrode surface. Under the optimal experimental conditions, the proposed sensing strategy expressed a superior linear relation with Hg²⁺ concentration from 10 fM to 1 nM. Moreover, a low detection limit of 3.3 fM with outstanding selectivity, repeatability, and stability for Hg²⁺ analysis was obtained. In addition, the proposed sensing strategy exhibited reasonable accuracy for real sample assay compared with the atomic fluorescence spectrometry method. From this work, it is suggested that by programming the analytes and the corresponding recognition element, other analytes might also be sensitively and selectively detected using the proposed method.

中文翻译：

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DNA修饰的三（4,4'-二羧酸-2,2'-联吡啶）三氯化钌（II）电化学发光和辅助DNA修饰的Hg ²⁺检测的氮化碳量子点

准确测定有害Hg ²⁺对于环境安全和人体健康尤为重要。在这项工作中，使用Hg ²⁺作为电致发光（ECL）试剂和相应的共反应物的桥，首次可控地制备了一种新型的自增强ECL纳米材料。详细地，使用了用DNA1（Ru-DNA1）修饰的三（4,4'-二羧酸-2,2'-联吡啶基）二氯化钌（II）和与DNA2连接的类石墨氮化碳量子点（QDs-DNA2）。分别作为ECL试剂和共反应剂。在存在Hg ²⁺的情况下，它们可以通过T-Hg ²⁺结合在一起形成自增强的ECL纳米材料（Ru- DNA1- Hg ²⁺ -QDs-DNA2）。-T双工结构。ECL信号强度与Hg ²⁺浓度成正比。在此基础上，可以通过简单地修饰电极表面上的ECL纳米材料来实现Hg ^2+的灵敏和选择性检测。在最佳实验条件下，提出的传感策略与Hg ²⁺浓度从10 fM到1 nM表现出良好的线性关系。此外，低检测限为3.3 fM，对Hg ²⁺具有出色的选择性，可重复性和稳定性获得分析。此外，与原子荧光光谱法相比，所提出的传感策略对真实样品的分析显示出合理的准确性。通过这项工作，建议通过对分析物和相应的识别元素进行编程，使用所提出的方法还可以灵敏地和选择性地检测其他分析物。