A novel method of catalytic hairpin assembly (CHA) induced dual signal enhancement is developed for rapid detection of miRNA based on fluorescence light-up silver nanocluster (Ag NC). By the hybridization of a hairpin DNA and a single-stranded DNA, a unique probe is firstly designed. In the terminals of this probe, DNA-Ag NCs can be formed and display very weak fluorescence. In the presence of the target miRNA, the reaction of CHA can be triggered, forming two kinds of double-stranded complexes, in which the terminal DNA-Ag NCs are in close proximity to G-rich overhangs and the fluorescent signal can be dramatically enhanced. Compared with many other enzyme-based amplification strategies, this one exhibits distinct advantages of simplicity in experimental operation and a rapid detection process (within 1 h). Moreover, this assay exhibits an excellent selectivity and is successfully applied in the detection of miRNAs in complex biological media, which confirms the reliability and practicality of this protocol.

中文翻译：

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催化发夹组装诱导双信号增强，使用荧光点亮银纳米团簇快速检测 miRNA

开发了一种新的催化发夹组装 (CHA) 诱导双信号增强方法，用于基于荧光点亮银纳米簇 (Ag NC) 快速检测 miRNA。通过发夹DNA和单链DNA的杂交，首先设计了独特的探针。在该探针的末端，可以形成 DNA-Ag NCs 并显示出非常弱的荧光。在目标miRNA存在的情况下，可触发CHA反应，形成两种双链复合物，其中末端DNA-Ag NCs紧邻富含G的突出端，荧光信号可显着增强. 与许多其他基于酶的扩增策略相比，该策略具有实验操作简单和检测过程快速（1小时内）的明显优势。而且，