Dual triggers induced disassembly of DNA polymer decorated silver nanoparticle for ultrasensitive electrochemical Pb2+ detection
Dual triggers induced disassembly of DNA polymer decorated silver nanoparticle for ultrasensitive electrochemical Pb2+ detection
复制标题
双触发器诱导 DNA 聚合物修饰的银纳米颗粒分解，用于超灵敏电化学 Pb2 检测
DOI：
10.1016/j.aca.2018.06.050
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发表时间：
2018
影响因子：
6.2
通讯作者：
Yuan Ruo
中科院分区：
文献类型：
--
作者：
Xie Xiyue;Chai Yaqin;Yuan Yali;Yuan Ruo
在这项工作中，设计了一种基于支链 DNA 聚合物高效分解和靶标转变循环放大的新型无标记生物传感器，用于铅离子 (Pb2+) 的超灵敏电化学测定。通过杂交链式反应（HCR）形成的支链DNA聚合物首先被固定在电极上，并作为负载丰富的银纳米颗粒（AgNPs）的载体，产生极高的初始电流信号输出。然后，通过靶标跃迁循环扩增产生的分子触发器T1和T2可以分别分解支链DNA聚合物的主链和侧链，电流显着降低，从而实现Pb2+的灵敏检测。与传统的一触发诱导拆卸策略相比，该方法表现出更高的分解效率。实验数据表明，该生物传感器对Pb2+检测具有优越的性能，检测限低至0.24 pM。此外，所建立的策略为实现其他金属离子的超灵敏检测开辟了一条新途径。
In this work, a new label-free biosensor based on highly effective decomposition of a branched DNA polymer and target-transition recycling amplification was designed for ultrasensitive electrochemical determination of lead ion (Pb2+). The branched DNA polymer formed by hybridization chain reaction (HCR) was first immobilized on electrode and served as the carrier for loading abundant silver nanoparticle (AgNPs) to generate an extremely high initial current signal output. Then, the molecular triggers T1and T2, which were produced through a target-transition recycling amplification, could respectively disassemble the backbone and side chain of the branched DNA polymer with remarkably decreased current for sensitive detection of Pb2+. Compared with traditional one-trigger induced disassembly strategy, the proposed approach exhibited higher decomposition efficiency. The experimental data showed that this developed biosensor had a superior performance for Pb2+detection with a low detection limit down to 0.24 pM. Furthermore, the established strategy set up a new way to achieve the ultrasensitive detection of other metal ions.