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.

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在这项工作中，已建立了基于等温链置换聚合酶反应（ISDPR）的三维DNA机器。DNA助听器在磁珠阻塞表面上的行走行为也已通过添加不同的核酸嵌段进行了研究。DNA Walker的“腿”可以与名为H1的发夹结构DNA杂交并导致其打开。新暴露的茎将与底漆相互作用。在聚合酶和dNTPs的帮助下发生了链交换，因此“腿”已被置换，DNA Walker可以被推动在表面移动。但是核酸块可能会增加位阻并阻碍这一过程，这与人类在崎paths不平的道路上行走的行为相似。通过更改这些块，例如结构，数量，和块的长度，DNA Walker的移动已受到控制。而且，将其用于DNA检测的结果令人满意。检测限为21.6 pM。而且，该方法已成功应用于复杂的生物样品中。

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