Yin Zihao, Li Shunmei, Liu Xiaoju, Yuan Ruo, Xiang Yun
Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Dalton Trans. 2023 Dec 12;52(48):18473-18479. doi: 10.1039/d3dt03346e.
Sensitively monitoring metallothionein (MT), a heavy metal-binding protein with substantial cysteine content, is of significance for evaluating heavy metal poisoning in both humans and animals. Based on a new metal ion-coordinated DNA probe and the heavy metal ion binding capability of MT, as well as the substantial signal enhancement of the hybridization chain reaction (HCR) and rolling circle amplification (RCA), we demonstrate a highly sensitive fluorescence MT detection assay. MT binds the metal ions in the hairpin structured, metal ion-coordinated DNA probe to switch its hairpin structure into ssDNA, which triggers subsequent RCA reactions and HCRs to open plenty of fluorescently quenched signal hairpins to exhibit drastically amplified fluorescence recovery for assaying MT down to 0.58 nM within a dynamic range of 1-320 nM. In addition, the investigation of low contents of MT in diluted human serum by such an assay has also been verified, indicating its promising application potential for diagnosing heavy metal poisoning.
灵敏地监测金属硫蛋白（MT），一种富含半胱氨酸的重金属结合蛋白，对于评估人类和动物的重金属中毒具有重要意义。基于一种新型金属离子配位DNA探针以及MT的重金属离子结合能力，再结合杂交链式反应（HCR）和滚环扩增（RCA）的显著信号增强作用，我们展示了一种高灵敏度的荧光MT检测方法。MT与发夹结构的金属离子配位DNA探针中的金属离子结合，将其发夹结构转变为单链DNA，从而触发后续的RCA反应和HCR，打开大量荧光淬灭的信号发夹，实现荧光恢复的大幅放大，用于检测MT，在1 - 320 nM的动态范围内，检测限低至0.58 nM。此外，通过该方法对稀释人血清中低含量MT的研究也得到了验证，表明其在诊断重金属中毒方面具有广阔的应用潜力。
