An Electrochemical Biosensor for Sensitive Detection of MicroRNA-155: Combining Target Recycling with Cascade Catalysis for Signal Amplification
An Electrochemical Biosensor for Sensitive Detection of MicroRNA-155: Combining Target Recycling with Cascade Catalysis for Signal Amplification
复制标题
用于灵敏检测 microrna-155 的电化学生物传感器：将靶标回收与级联催化相结合进行信号放大
DOI：
10.1021/am507059n
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发表时间：
2015-01-14
影响因子：
9.5
通讯作者：
Yuan, Ruo
中科院分区：
文献类型：
--
作者：
Wu, Xiaoyan;Chai, Yaqin;Yuan, Ruo
基于催化发夹组装靶回收和级联电催化（细胞色素c（Cyt c）和醇氧化酶（AOx））放大信号，构建了一种新的电化学生物传感器，用于microRNA（miRNA）的高灵敏检测。值得指出的是，靶循环仅基于链置换过程实现，而没有核酸酶的帮助。此外，多孔二氧化钛纳米球的合成，它可以提供更大的表面积的铂纳米粒子（PtNPs）包裹，并相应地提高固定的DNA链1（S1）和细胞色素c的量。在模拟乙醇-乙醛反应的基础上，利用AOx催化乙醇生成乙醛，同时生成高浓度的H2 O2，再通过PtNPs和Cyt c的电催化实现级联放大。这种新设计的生物传感器提供了从0.8 fM到1 nM的miRNA-155的灵敏检测，检测限相对较低，为0.35 fM。
In this work, a new electrochemical biosensor based on catalyzed hairpin assembly target recycling and cascade electrocatalysis (cytochrome c (Cyt c) and alcohol oxidase (AOx)) for signal amplification was constructed for highly sensitive detection of microRNA (miRNA). It is worth pointing out that target recycling was achieved only based on strand displacement process without the help of nuclease. Moreover, porous TiO2 nanosphere was synthesized, which could offer more surface area for Pt nanoparticles (PtNPs) enwrapping and enhance the amount of immobilized DNA strand 1 (S1) and Cyt c accordingly. With the mimicking sandwich-type reaction, the cascade catalysis amplification strategy was carried out by AOx catalyzing ethanol to acetaldehyde with the concomitant formation of high concentration of H2O2, which was further electrocatalyzed by PtNPs and Cyt c. This newly designed biosensor provided a sensitive detection of miRNA-155 from 0.8 fM to 1 nM with a relatively low detection limit of 0.35 fM.