State Key Lab of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.
Nanoscale. 2019 May 30;11(21):10339-10347. doi: 10.1039/c9nr01666j.
Recent advances have proven solid-state nanopores as a powerful analysis platform that enables label-free and separation-free single-molecule analysis. However, the relatively low resolution still limits its application because many chemicals or targets with small sizes could not be recognized in a label-free condition. In this paper, we provide a possible solution that uses solid-state nanopores for small species signaling via the transition of huge DNA assembly products. DNAzyme responding to metal ions and the hybridization chain reaction (HCR) generating nanopore-detectable dsDNA concatamers are used as the transition model set. By the two-step DNAzyme-HCR transition, Pb2+ that was too tiny to be sensed was successfully recognized by the nanopore. The whole process happened in a completely homogeneous solution without any chemical modification. During condition optimization, we also discussed one possible application challenge that may affect the HCR signal-background distinction. Solid-state nanopores provide a potential solution to this challenge due to its ability to profile product length or even 3D structure information.
最近的进展证明，固态纳米孔是一种强大的分析平台，能够实现无需标记和无需分离的单分子分析。然而，相对较低的分辨率仍然限制了它的应用，因为许多尺寸较小的化学物质或目标物在无需标记的条件下无法被识别。在本文中，我们提供了一种可能的解决方案，即使用固态纳米孔通过巨大的 DNA 组装产物的转变来对小物种进行信号传递。作为转变模型集，我们使用了响应金属离子的 DNA 酶和产生可被纳米孔检测到的双链 DNA 连接物的杂交链式反应 (HCR)。通过两步的 DNA 酶-HCR 转变，成功地通过纳米孔识别出了太小而无法被感知的 Pb2+。整个过程在完全均相的溶液中发生，没有任何化学修饰。在条件优化过程中，我们还讨论了一个可能影响 HCR 信号背景区分的应用挑战。由于固态纳米孔能够分析产物长度甚至 3D 结构信息，因此为解决这个挑战提供了一种潜在的解决方案。
