DNA walker是一种新型高效分子机器，在生物传感器领域具有广泛的应用前景，但其运动轨迹不可控、运动路程短和运动速度慢严重制约了DNA walker生物传感器的发展。项目拟深入研究轨道的制备和马达的构建，创建一种高灵敏、快速的DNA walker生物传感器。通过对纳米金表面修饰DNA分子的机理研究和状态调控，显著提高其均一性和驱动马达的反应效率，实现DNA walker运动轨迹的可控；通过创造性耦合催化核酸自组装与酶辅助信号放大反应，设计新型滚动马达，进而增大DNA walker行走链与轨道接触面积，提升DNA walker运动路程和速度。基于以上技术创新与突破，构建“下一代”高性能的三维DNA walker生物传感器，并以此开发病原菌检测新方法，从而有效推动DNA walker生物传感器的发展，拓展其应用范围。

As a novel, high-performance molecular machine, DNA walker possesses widespread prospect in biosensor’s application. However, its development is seriously constrained by the uncontrollable locomotion trial, short moving distance and slow motion speed. Our project is specified in the study of DNA walker’s “track” and “motor”, aiming to establish a high sensitive, rapid DNA walker biosensor. For one thing, the mechanism and situation of the surface DNA on “spherical nucleic acid-gold nanoparticle (SNA-AuNPs) three dimensional track” are studied and regulated, through which the homogeneity of track and efficiency of the motor are improved, hence achieving the control of locomotion trial; For another thing, the catalyzed hairpin assembly (CHA) reaction is creatively coupled with enzyme assisted signal amplification (EASA) to build a double driving “rolling motor”, which sets it apart from traditional DNA molecular motor and expands the contacting area of walker strand and track, presenting a silver lining to largely improve the reaction speed. On the basis of above technical innovations, this project focuses on constructing the high-performance three dimensional DNA walker, and further exploiting effective detection method for pathogen bacteria. With the accomplishment of this project, a great development of DNA walker biosensor and its wide-range application can be expected.