Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei, China.
Anal Bioanal Chem. 2019 Jul;411(18):4055-4061. doi: 10.1007/s00216-019-01604-9. Epub 2019 Jan 28.
In this work, a three-dimensional DNA machine based on the isothermal strand-displacement polymerase reaction (ISDPR) has been constructed. The walking behavior of a DNA walker on the obstructive surface of magnetic beads has also been studied by adding different nucleic acid blocks. The "leg" of the DNA walker could hybridize with a hairpin structure DNA named H1 and lead to the opening of it. And the newly exposed stem would interact with a primer. A strand exchange has happened with the assistance of polymerase and dNTPs, so that the "leg" has been displaced and the DNA walker could be pushed to move on the surface. But the nucleic acid blocks could increase steric hindrance and obstruct this process, which is similar to the behavior of human beings walking on craggy paths. Through changing these blocks, such as the structure, the amount, and the length of blocks, the movement of the DNA walker has been controlled. What's more, the results of its application for DNA detection are satisfactory. The limit of detection is 21.6 pM. Also, this method has been successfully applied in complex biological samples. Graphical abstract ᅟ.
在这项工作中，构建了基于等温链置换聚合酶反应（ISDPR）的三维 DNA 机器。通过添加不同的核酸块，研究了 DNA walker 在磁性珠阻塞表面上的行走行为。DNA walker 的“腿”可以与一种名为 H1 的发夹结构 DNA 杂交，导致其打开。新暴露的茎会与引物相互作用。在聚合酶和 dNTP 的辅助下发生链交换，从而使“腿”移位，DNA walker 可以在表面上移动。但是，核酸块会增加空间位阻并阻碍这个过程，这类似于人类在崎岖小路上行走的行为。通过改变这些块，如块的结构、数量和长度，可以控制 DNA walker 的运动。此外，其用于 DNA 检测的应用结果令人满意。检测限为 21.6 pM。此外，该方法已成功应用于复杂的生物样本。
