Electrochemical DNA (e-DNA) biosensors are feasible tools for disease monitoring, with their ability to translate hybridization events between a desired nucleic acid target and a functionalized transducer, into recordable electrical signals. Such an approach provides a powerful method of sample analysis, with a strong potential to generate a rapid time to result in response to low analyte concentrations. Here, we report a strategy for the amplification of electrochemical signals associated with DNA hybridization, by harnessing the programmability of the DNA origami method to construct a sandwich assay to boost charge transfer resistance (R_CT) associated with target detection. This allowed for an improvement in the sensor limit of detection by two orders of magnitude compared to a conventional label-free e-DNA biosensor design and linearity for target concentrations between 10 pM and 1 nM without the requirement for probe labeling or enzymatic support. Additionally, this sensor design proved capable of achieving a high degree of strand selectivity in a challenging DNA-rich environment. This approach serves as a practical method for addressing strict sensitivity requirements necessary for a low-cost point-of-care device.

中文翻译：

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使用目标捕获 DNA 折纸瓷砖的电化学 DNA 生物传感器中的信号放大

电化学 DNA (e-DNA) 生物传感器是用于疾病监测的可行工具，它们能够将所需核酸靶标和功能化传感器之间的杂交事件转化为可记录的电信号。这种方法提供了一种强大的样品分析方法，具有产生快速时间以响应低分析物浓度的强大潜力。在这里，我们报告了一种放大与 DNA 杂交相关的电化学信号的策略，通过利用 DNA 折纸方法的可编程性构建夹心测定法来提高电荷转移电阻 ( R _CT) 与目标检测相关联。与传统的无标记 e-DNA 生物传感器设计相比，这可以将传感器的检测极限提高两个数量级，并且目标浓度的线性范围在 10 pM 和 1 nM 之间，而无需探针标记或酶促支持。此外，这种传感器设计被证明能够在具有挑战性的富含 DNA 的环境中实现高度的链选择性。这种方法是一种实用方法，可满足低成本床旁设备所需的严格灵敏度要求。