Herein, a highly sensitive electrochemical genosensor is proposed by the construction of an innovative DNA walking machine. Generally, a number of tetrahedral DNA (TDNA)-supported tracks and walkers are comodified on the electrode surface. DNA walking is inhibited in the absence of target DNA. After the interaction between a DNA walker strand and target DNA, a single-stranded primer sequence could be released, which initiates subsequent rolling circle amplification (RCA). The generated long single-stranded product contains multiple DNAzyme cores, which facilitate highly efficient cleavage of track strands and subsequent DNA walking. The electrode then loses the ability to localize silver nanoparticles (AgNPs) as the electrochemical species. Thus, when the reduced silver stripping current is recorded, a highly sensitive method for the detection of DNA is fabricated. Under optimal conditions, it achieves an admirable sensitivity with the limit of detection as low as 0.1 fM. Satisfactory specificity is also guaranteed. In addition, the practicality is further confirmed by applying human serum samples, which show great potential utility for clinical diagnosis.

中文翻译：

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具有多个DNA酶核心的高度灵敏的基因传感耦合滚动环扩增，可用于DNA行走。

在此，通过构造创新的DNA步行机提出了高灵敏度的电化学基因传感器。通常，在电极表面上共修饰了许多支持四面体DNA（TDNA）的走线和助步器。在不存在目标DNA的情况下，DNA行走受到抑制。DNA Walker链与目标DNA相互作用后，可以释放单链引物序列，从而启动随后的滚环扩增（RCA）。生成的长单链产物包含多个DNAzyme核心，这些核心有助于高效切割轨道链和随后的DNA步移。然后，电极失去了将银纳米颗粒（AgNPs）定位为电化学物质的能力。因此，当记录到减少的银剥离电流时，制造了一种用于检测DNA的高灵敏度方法。在最佳条件下，它的检测极限低至0.1 fM，可实现令人赞叹的灵敏度。还可以保证令人满意的特异性。另外，通过应用人血清样品进一步证实了实用性，这显示出对临床诊断的巨大潜在效用。