Herein, we constructed a fluorescence biosensor for the ultra-sensitive analysis of microRNAs (miRNAs) by combining DNA hairpins transition triggered strand displacement amplification (DHT-SDA) with primer exchange reaction (PER). Target miRNA initiated DHT-SDA to facilitate the generation of multiple single-stranded DNA (ssDNA) as PER primer, which was extended into a long ssDNA. The biosensor is successfully utilized in detecting miRNAs with high sensitivity (limit of detection for miRNA-21 was 58 fM) and a good linear relationship between 100 nM and 100 fM. By simply changing the DNA hairpin sequence, the constructed biosensor can be extended to analyze another miRNAs. Moreover, the biosensor has the feasibility of detecting miRNAs in real samples with satisfactory accuracy and reliability. Therefore, the fluorescent biosensor has great application potential in clinical diagnosis.

中文翻译：

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荧光生物传感器通过整合 DNA 发夹转变介导的链置换扩增与引物交换反应来检测 microRNA

在此，我们通过将DNA发夹转换触发链置换扩增（DHT-SDA）与引物交换反应（PER）相结合，构建了一种用于超灵敏分析microRNA（miRNA）的荧光生物传感器。目标miRNA启动DHT-SDA以促进多条单链DNA（ssDNA）的生成，作为PER引物，将其延伸成长的ssDNA。该生物传感器成功地用于检测miRNA，灵敏度高（miRNA-21的检测限为58 fM），并且在100 nM和100 fM之间具有良好的线性关系。通过简单地改变DNA发夹序列，构建的生物传感器可以扩展到分析其他miRNA。此外，该生物传感器具有检测真实样本中miRNA的可行性，并且具有令人满意的准确性和可靠性。因此，荧光生物传感器在临床诊断中具有巨大的应用潜力。