Department of Biomedical Engineering, University of Strathclyde, Glasgow G1 1QE, United Kingdom.
Biohybrid Materials, Department of Bioproducts and Biosystems, Aalto University, 00076 Aalto, Finland.
ACS Sens. 2023 Apr 28;8(4):1471-1480. doi: 10.1021/acssensors.2c02469. Epub 2023 Mar 13.
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 () 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.
电化学 DNA（e-DNA）生物传感器是疾病监测的可行工具，其能够将目标核酸与功能化换能器之间的杂交事件转化为可记录的电信号。这种方法为样品分析提供了一种强大的方法，具有快速产生结果的强大潜力，以应对低浓度的分析物。在这里，我们报告了一种通过利用 DNA 折纸方法的可编程性来构建三明治测定法来放大与 DNA 杂交相关的电化学信号的策略，以提高与目标检测相关的电荷转移电阻（）。与传统的无标记 e-DNA 生物传感器设计相比，这使得传感器的检测限提高了两个数量级，并且在无需探针标记或酶支持的情况下，目标浓度在 10 pM 到 1 nM 之间具有线性关系。此外，该传感器设计在具有挑战性的富含 DNA 的环境中表现出高度的链选择性。这种方法为低成本即时检测设备所需的严格灵敏度要求提供了一种实用的方法。
