Abstract：
the accurate, reliable and specific analysis of foodborne pathogenic bacteria is vital for human health and safety. Staphylococcus aureus (S. aureus), as a common bacterium, is regularly found in food, water, and other biological samples. Herein, a signal-off electrochemical DNA sensor (E-DNA sensor) was designed for the sensitive detection ofS. aureusamplified withthecombination of a dna walker and pb2+-specific dnazyme. In this work, vancomycin functionalized gold nanoclusters (Van@Au NCs) and an aptamer strand as identification units were modified at the termini of two proximity probes. upon the addition of targetS. aureus, a dual-recognition binding-induced dna walker was driven by the formation of pba dual-recognition binding-induced dna walker was driven by the formation of pba dual-recognition binding-induced dna walker was driven by the formation of pba dual-recognition binding-induced dna walker was driven by the formation of pb2+-dependent dnazyme, achieving the conversion of oneS. aureus to many intermediate dna (t) strands. then, the released t strands hybridized with methylene blue-tagged hairpin dna (h-mb) on the electrode. consequently, the conformational alteration of t strands reduced the electron transfer efficiency of mb to the electrodeinterface (signal-off). therefore, sensitive analysis of S. aureus was readily acquired within a range of 10-107 CFU/mL and a low detection limit at 1 CFU/mL. Undoubtedly, dual recognition by aptamer and vancomycin in an integrated scheme brought about a good recognition performance of S. aureus in complex samples, as well as an efficient annihilation of harmful pathogenic bacteria during the experiment.
摘要：
准确的,可靠和具体的食源性致病菌分析对人体健康和安全至关重要。金黄色葡萄球菌（S。金黄色葡萄球菌)，作为一种常见的细菌，经常在食物中发现，水,和其他生物样本。在这里，设计了一种信号关闭的电化学DNA传感器（E-DNA传感器），用于S的灵敏检测。dnawalker和pb2+特异性dnazyme的组合放大了金黄色。在这项工作中,在两个邻近探针的末端修饰万古霉素官能化金纳米簇(Van@AuNC)和作为识别单元的适体链。在添加目标时。金黄色葡萄球菌,双识别结合诱导的dna步行者由pba的形成驱动双识别结合诱导的dna步行者由pba的形成驱动双识别结合诱导的dna步行者由pba的形成驱动双识别结合诱导的dna步行者由pb2+-dnazyme的形成驱动，实现一个S的转换。金黄色葡萄球菌到许多中间dna(t)链。然后,释放的t链在电极上与亚甲基蓝标记的发夹dna(h-mb)杂交。因此,t链的构象变化降低了mb向电极界面的电子转移效率（信号关闭）。因此,在10-107CFU/mL的范围内容易获得金黄色葡萄球菌的灵敏分析，并且在1CFU/mL时具有较低的检测限。毫无疑问,适体和万古霉素在一个整合方案中的双重识别带来了对复杂样品中金黄色葡萄球菌的良好识别性能，以及在实验过程中有效消灭有害致病菌。
