DNA transducer-triggered signal switch for visual colorimetric bioanalysis.
DNA transducer-triggered signal switch for visual colorimetric bioanalysis.
复制标题
用于视觉比色生物分析的 DNA 传感器触发信号开关。
DOI：
10.1038/srep11190
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发表时间：
2015-06-10
影响因子：
4.6
通讯作者：
Ding S
中科院分区：
文献类型：
--
作者：
Chen W;Yan Y;Zhang Y;Zhang X;Yin Y;Ding S
一种简单而通用的比色生物传感器已被开发用于灵敏和特异地检测广泛的生物分子，如寡核苷酸和适体识别的目标。结合信号转导子和基于催化发夹组装（CHA）的信号扩增，靶DNA与发夹DNA结合以形成新的核酸序列，并在转导子中产生立足点，用于启动CHA的再循环扩增反应。催化组装过程产生大量富含G的DNA。在氯化血红素存在下，富含G的DNA形成G-四链体/氯化血红素复合物并模拟辣根过氧化物酶活性，其催化比色反应。在最佳条件下，合成的靶DNA在50 ~ 200 nM范围内线性关系良好，检测限为32 pM。该策略已成功应用于S. pneumoniae低至156 CFU mL−1，并对密切相关的链球菌和主要病原菌显示出良好的特异性。此外，所开发的方法能够成功地进行可视化分析S。通过肉眼观察临床样品中的肺炎。重要的是，该方法证明了用于灵敏地检测寡核苷酸或适体识别的靶标的优异的测定通用性。
A simple and versatile colorimetric biosensor has been developed for sensitive and specific detection of a wide range of biomolecules, such as oligonucleotides and aptamer-recognized targets. Combining the signal transducer and catalyzed hairpin assembly (CHA)-based signal amplification, the target DNA binds with the hairpin DNA to form a new nucleic acid sequence and creates a toehold in the transducer for initiating the recycle amplification reaction of CHA. The catalyzed assembly process produces a large amount of G-rich DNA. In the presence of hemin, the G-rich DNA forms G-quadruplex/hemin complex and mimic horseradish peroxidase activity, which catalyzes a colorimetric reaction. Under optimal conditions, the calibration curve of synthetic target DNA has good linearity from 50 pM to 200 nM with a detection limit of 32 pM. This strategy has been successfully applied to detect S. pneumoniae as low as 156 CFU mL−1, and shows a good specificity against closely related streptococci and major pathogenic bacteria. In addition, the developed method enables successful visual analysis of S. pneumoniae in clinical samples by the naked eye. Importantly, this method demonstrates excellent assay versatility for sensitively detecting oligonucleotides or aptamer-recognized targets.