Gebze Technical University, Department of Environmental Engineering, 41400 Gebze, Kocaeli, Turkey.
Izmir Institute of Technology, Department of Environmental Engineering, 35430 Urla, İzmir, Turkey.
Bioelectrochemistry. 2020 Oct;135:107553. doi: 10.1016/j.bioelechem.2020.107553. Epub 2020 May 15.
Applications of molecular techniques to elucidate identity or function using biomarkers still remain highly empirical and biosensors are no exception. In the present study, target-specific oligonucleotide probes for E. coli K12 were designed thermodynamically and applied in an electrochemical DNA biosensor setup. Biosensor was prepared by immobilization of a stem-loop structured probe, modified with a thiol functional group at its 5' end and a biotin molecule at its 3' end, on a gold electrode through self-assembly. Mercaptopropionic acid (MPA) was used to optimize the surface probe density of the electrode. Hybridization between the immobilized probe and the target DNA was detected via the electrochemical response of streptavidin-horseradish peroxidase in the presence of the substrate. The amperometric response showed a linear relationship with the target DNA concentration, ranging from 10 and 400 nM, with a correlation coefficient of 0.989. High selectivity and good repeatability of the biosensor showed that the thermodynamic approach to oligonucleotide probe design can be used in development of electrochemical DNA biosensors.
应用分子技术通过生物标志物来阐明身份或功能仍然高度依赖经验，生物传感器也不例外。在本研究中，我们从热力学角度设计了针对大肠杆菌 K12 的靶向特异性寡核苷酸探针，并将其应用于电化学 DNA 生物传感器设置中。生物传感器通过将带有巯基官能团的 5' 端和生物素分子的 3' 端修饰的茎环结构探针自组装到金电极上来制备。使用巯基丙酸 (MPA) 来优化电极表面探针的密度。在存在底物的情况下，通过电化学响应检测固定化探针与靶 DNA 之间的杂交。安培计响应与靶 DNA 浓度呈线性关系，范围为 10 至 400 nM，相关系数为 0.989。生物传感器具有高选择性和良好的重复性，表明基于热力学的寡核苷酸探针设计方法可用于开发电化学 DNA 生物传感器。
