Double loop-stem hairpins mediated hybridization chain reaction: A multifunctional DNA molecular tool to produce the intact aptamer for label-free biosensing
Double loop-stem hairpins mediated hybridization chain reaction: A multifunctional DNA molecular tool to produce the intact aptamer for label-free biosensing
复制标题
双环-茎发夹介导的杂交链式反应：一种生产无标记生物传感完整适配子的多功能DNA分子工具
DOI：
10.1016/j.snb.2022.132327
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发表时间：
2022-07-08
影响因子：
8.4
通讯作者：
Li, Yingchun
中科院分区：
文献类型：
--
作者：
Peng, Xin;Yang, Jiao;Li, Yingchun
A DNA molecular tool based on the double loop-stem (DL) hairpins mediated hybridization chain reaction (D-HCR) system was proposed to produce the intact G-quadruplex (InG4) aptamers for enzyme-free and label-free biosensing. The D-HCR system was triggered by targets to produce the cross-sequential nanowires of double -stranded and single-stranded DNA (DS nanowire) through the alternating strand displacement events of DL hairpins. Unlike the split G4 (SpG4) aptamers in current HCR, the formation of DS nanowires was accompanied by the release of previously locked InG4 aptamers. Impressively, we tested that the fluorescence enhancement effect of InG4 aptamer on Thioflavin T (ThT) was16.49-fold higher than that of the SpG4 aptamer. To demon-strate the flexibility of the InG4 aptamer-based D-HCR system, we established a fluorescence biosensor depending on the fluorescence enhancement of InG4/ThT with a detection limit of 4.60 pM, and a colorimetric biosensor relying on the catalytic activity of InG4/Hemin with a detection limit of 13.60 pM. The above-mentioned biosensors showed high specificity against interfering miRNAs and excellent detection performance in living cells and lysates. Our D-HCR system provides an avenue for preparing DS nanowires to produce the intact aptamer in each hairpin, which may be valuable to prompt the development of HCR-aptamer technique.
