Dual-signal amplification strategy for miRNA sensing with high sensitivity and selectivity by use of single Au nanowire electrodes
Dual-signal amplification strategy for miRNA sensing with high sensitivity and selectivity by use of single Au nanowire electrodes
复制标题
使用单金纳米线电极实现高灵敏度和选择性 miRNA 传感的双信号放大策略
DOI：
10.1016/j.bios.2019.02.023
复制
发表时间：
2019-04-15
影响因子：
12.6
通讯作者：
Li, Yongxin
中科院分区：
文献类型：
--
作者：
Tang, Haoran;Zhu, Jiahui;Li, Yongxin
MicroRNAs （miRNAs）已被用作生物标志物，更好地检测其表达谱在癌症的早期诊断中起着重要作用。在这项工作中，基于杂交/去杂交过程中的“信号开启”和“信号关闭”特征，采用一种简单的双信号放大策略，在单金纳米线电极（SAuNWEs）上构建了一种新型纳米传感器，用于miRNA-16检测。二茂铁标记适体捕获探针（Fc-CP-16）与巯基亚甲基蓝标记DNA探针（MB-CP）在SAuNWE上杂交形成双工DNA，由于miRNA-16与Fc-CP-16序列高度匹配，加入miRNA-16可导致双工结构解离。因此，剩余的MB-CP可以通过其互补序列的杂交，在Mg2+存在下倾向于恢复其发夹结构。在这个杂交/去杂交过程中，可以记录Fc和MB氧化峰的变化，双信号变化的总和（Delta I = Delta I-MB +竖条Delta I- Fc竖条）与miRNA-16浓度的对数之间存在线性关系，可以用来检测miRNA-16。包括miRNA提取在内，双信号扩增策略进行miRNA检测，在真实样品中进行2h左右的检测。这种新型纳米传感器具有体积小、选择性好、反应快、再生能力强等特点，能够满足细胞/细胞器中早期肿瘤标志物检测的需要。
MicroRNAs (miRNAs) have been applied as biomarkers and better detection of their expression profiles plays important roles in early diagnosis of cancers. In this work, a simple dual-signal amplification strategy has been used to construct a novel nanosensor on single Au nanowire electrodes (SAuNWEs) for miRNA-16 detection based on the "signal-on" and "signal-off" features during hybridization/de-hybridization process. The ferrocenelabeled aptamer capture probe (Fc-CP-16) is designed to hybridize with thiolated methylene blue-labeled DNA probe (MB-CP) on SAuNWE to form duplex DNA, and the addition of miRNA-16 can lead to the dissociation of duplex structure due to the highly matched sequences between miRNA-16 and Fc-CP-16. The remaining MB-CP can thus tend to recover its hairpin structure at the presence of Mg2+ through the hybridization of its complementary sequences. During this hybridization/de-hybridization process, the changes of Fc and MB oxidation peaks can be recorded, and there has a linear relationship between the sum of dual-signal changes (Delta I = Delta I-MB +vertical bar Delta I-FC vertical bar) and the logarithm of miRNA-16 concentrations, which can be used to detect miRNA-16. Including miRNA extraction, the dual-signal amplification strategy for miRNA sensing assay was carried out about 2h for the detection in real samples. This novel nanosensor has small dimension, good selectivity, rapid response and regeneration ability, which can satisfy the need for early cancer marker detection in cells/organelles.