The Affiliated Hospital, Department of Pharmacy, JiangXi University of Traditional Chinese Medicine, JiangXi, 330004, China.
Anal Sci. 2021 Sep 10;37(9):1221-1226. doi: 10.2116/analsci.20P431. Epub 2021 Jan 15.
A convenient homogeneous electrochemical thrombin sensor based on potential-assisted Au-S deposition and a dual signal amplification strategy was established in this study. Potential-assisted Au-S deposition does not require the modification of the gold electrode, thus eliminating the tedious pre-modification of the electrode. To better amplify the output signal, both ends of the signal hairpin probes were modified with a new electroactive substance, tetraferrocene, which was synthesized by the authors. Thrombin was immediately hybridized with a thiol-modified probe to open the stem-loop structure. After chain hybridization, thrombin was replaced and participated in the next round of the reaction; thus, the cascade amplification of the signal was realized. The hybrid chain formed an Au-S deposition under potential assistance, and the electrochemical signal of tetraferrocene could then be measured through differential pulse voltammetry (DPV) and consequently used for the quantitative detection of target thrombin. In addition, the detection limit of thrombin was as low as 0.06 pmol/L, and the detection of common interfering proteins was highly specific.
本研究建立了一种基于电位辅助 Au-S 沉积和双信号放大策略的简便均相电化学凝血酶传感器。电位辅助 Au-S 沉积不需要对金电极进行修饰，从而省去了电极繁琐的预修饰过程。为了更好地放大输出信号，信号发夹探针的两端都用作者合成的新型电活性物质四(二茂铁基)卟啉进行了修饰。凝血酶立即与巯基修饰的探针杂交，打开茎环结构。链杂交后，凝血酶被取代并参与下一轮反应，从而实现信号的级联放大。在电位辅助下形成 Au-S 沉积，然后可以通过差分脉冲伏安法（DPV）测量四(二茂铁基)卟啉的电化学信号，从而用于定量检测目标凝血酶。此外，凝血酶的检测限低至 0.06pmol/L，对常见干扰蛋白的检测具有高度特异性。
