A novel and adjustable lamp based on competitive interaction among dsDNA-SYBR Green I (SGI), ion quencher, and analyte was designed for bioanalysis. The “filament” and switch of the lamp could be customized by employing different dsDNA and ion quencher. The poly(AT/TA) dsDNA was successfully screened as the most effective filament of the lamp. Two common ions, Hg²⁺ and Fe³⁺, were selected as the model switch, and the corresponding ligand molecules cysteine (Cys) and pyrophosphate ions (PPi) were selected as the targets. When the fluorescence-quenched dsDNA/SGI–ion complex was introduced into a target-containing system, ions could be bound by competitive molecules and separate from the complex, thereby lighting the lamp. However, no light was observed if the biomolecule could not snatch the metal ions from the complex. Under the optimal conditions, sensitive and selective detection of Cys and PPi was achieved by the lamp, with practical applications in fetal bovine serum and human urine. This ion quencher regulated lamp for fluorescent bioassays is simple in design, fast in operation, and is more convenient than other methods. Significantly, as many molecules could form stable complexes with metal ions selectively, this ion quencher operated lamp has potential for the detection of a wide spectrum of analytes.

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设计了一种基于dsDNA-SYBR Green I（SGI），离子猝灭剂和分析物之间竞争性相互作用的新型可调灯，用于生物分析。可以通过使用不同的dsDNA和离子猝灭剂来定制灯的“灯丝”和开关。聚（AT / TA）dsDNA被成功筛选为最有效的灯丝。两种常见离子Hg ²⁺和Fe ³⁺选择，作为模型转换，并选择相应的配体分子半胱氨酸（Cys）和焦磷酸根离子（PPi）作为目标。当将荧光猝灭的dsDNA / SGI-离子复合物引入包含靶标的系统时，离子可能被竞争性分子束缚并与复合物分离，从而点亮了灯。然而，如果生物分子不能从络合物中夺走金属离子，则没有观察到光。在最佳条件下，该灯可对Cys和PPi进行灵敏和选择性的检测，并在胎牛血清和人尿中有实际应用。这种用于荧光生物测定的离子猝灭剂调节灯设计简单，操作快速，比其他方法更方便。重要的是，由于许多分子可以选择性地与金属离子形成稳定的络合物，

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