A triply amplified electrochemical lead(II) sensor by using a DNAzyme and via formation of a DNA-gold nanoparticle network induced by a catalytic hairpin assembly
A triply amplified electrochemical lead(II) sensor by using a DNAzyme and via formation of a DNA-gold nanoparticle network induced by a catalytic hairpin assembly
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DOI：
10.1007/s00604-019-3612-5
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发表时间：
2019-08-01
影响因子：
5.7
通讯作者：
Huang, Jiadong
中科院分区：
文献类型：
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作者：
Song, Xiaolei;Wang, Yu;Huang, Jiadong
描述了铅 (II) 离子的放大电化学生物传感方案。它利用 DNAzyme 辅助的靶标回收和催化发夹组装 (CHA)。发夹链（基于 Pb2+ 的 DNAzyme 的底物探针；称为 SP）由触发探针 (TP) 和附着在金纳米粒子 (AuNP) 上的捕获探针 1 组成。在与 SP 部分杂交的酶探针存在的情况下，Pb2+ 的引入会触发靶标回收并驱动靶标 Pb(II) 高度扩增地翻译为 TP。 CHA反应进一步由TP引发。修饰后的 AuNP 作为连接单元，导致在电极上形成 3D DNA-AuNP 网络（这是第三个放大步骤）。它可以通过静电相互作用结合带正电的氧化还原介体RuHex进行电化学检测。该生物传感器具有低检测限 (95 pM) 和涵盖 100 pM 至 5 muM Pb(II) 浓度范围的任何分析范围。它比其他二价金属离子具有选择性。它适用于测定实际样品中加标的 Pb2+。
An amplified electrochemical biosensing scheme is described for lead(II) ions. It is making use of DNAzyme-assisted target recycling and catalytic hairpin assembly (CHA). The hairpin strand (substrate probe for the Pb2+-based DNAzyme; referred to as SP) is composed of trigger probe (TP) and a capture probe 1 attached to gold nanoparticles (AuNP). In the presence of the enzyme probe that partially hybridizes with SP, the introduction of Pb2+ triggers target recycling and drives the highly amplified translation of target Pb(II) to TP. The CHA reaction is further initiated by TP. The modified AuNP act as the connecting unit, and this leads to the formation of a 3D DNA-AuNP network on the electrode (which is the third amplification step). It can bind the positively charged redox mediator RuHex via electrostatic interaction for electrochemical detection. This biosensor has a low detection limit (95 pM) and any analytical range that covers the 100 pM to 5 mu M Pb(II) concentration range. It is selective over other divalent metal ions. It was applied to the determination of Pb2+ in spiked real-world samples.