Sensitive and accurate detection of multiplex foodborne pathogens is crucial for food safety. In this work, a dual-mode and dual-target biosensor regulated by a Tesla valve was established for simultaneously determining Escherichia coli O157:H7 (E. coli) and Salmonella typhimurium (S. T). Two zeolitic imidazolate framework (ZIF-8) signal probes decorated with electroactive materials (ferrocene or methylene blue), DNAzyme, and different phages were synthesized to specifically recognize the targets and generate fluorescent/electrochemical dual-mode signals. In the presence of bacteria, they were captured and enriched on two individual working electrodes through the modified 4-mercaptophenylboric acid. The encoded signal probes added on different working electrodes could be conjugated with the corresponding target bacteria depending on the specificity of phages. Under the acidic condition, the DNAzyme could catalyze click chemistry for fluorescent signals. Simultaneously, the released ferrocene and methylene blue from ZIF-8 could generate electrochemical signals at different potentials. Benefiting from the flow regulation feature of the Tesla valve, the triggered fluorescent and electrochemical signals in the two individual electrodes would not influence each other, achieving simultaneous dual-mode and dual-target determination of foodborne pathogens. It depicted good linearity ranged 10–10⁷ CFU mL⁻¹. And the corresponding detection of limits were 5 CFU mL⁻¹ and 8 CFU mL⁻¹ for two bacteria, respectively. A low false positive was realized through the dual-mode strategy. The proposed biosensor can not only on-site, specifically, and sensitively determine E. coli and S. T, but also provide the wide prospect in rapid screening of other foodborne pathogens.

灵敏、准确地检测多种食源性病原体对于食品安全至关重要。本工作建立了一种由特斯拉阀调节的双模式双目标生物传感器，用于同时测定大肠杆菌O157:H7（E. coli）和鼠伤寒沙门氏菌（S.T ）。合成了两种用电活性材料（二茂铁或亚甲蓝）、DNAzyme 和不同噬菌体装饰的沸石咪唑酯框架（ZIF-8）信号探针，以特异性识别目标并产生荧光/电化学双模式信号。在存在细菌的情况下，它们通过修饰的 4-巯基苯硼酸在两个单独的工作电极上被捕获和富集。添加在不同工作电极上的编码信号探针可以根据噬菌体的特异性与相应的目标细菌结合。在酸性条件下，DNAzyme 可以催化点击化学反应产生荧光信号。同时，ZIF-8释放的二茂铁和亚甲蓝可以在不同电位下产生电化学信号。受益于特斯拉阀的流量调节特性，两个单独电极触发的荧光和电化学信号不会相互影响，实现食源性病原体的双模式、双目标同时测定。^{它描绘了10-10 7}  CFU mL ^-1范围内的良好线性。两种细菌相应的检测限分别为5 CFU mL ^-1和8 CFU mL ^-1。通过双模式策略实现了低误报。该生物传感器不仅可以现场、特异、灵敏地测定大肠杆菌和S.T，而且为其他食源性病原体的快速筛查提供了广阔的前景。