AbstractThe authors describe an electrochemical aptasensor for thrombin that is based on the use of a glassy carbon electrode (GCE) modified with polydopamine that is loaded with silver nanoparticles (PDA/AgNPs). The use of AgNPs improves the conductivity of the film and increases the surface area of the GCE. PDA was deposited on the GCE via self-polymerization, and the thrombin binding aptamer was grafted onto the PDA-modified GCE by a single step reaction. Residual electrode surface was blocked with 6-mercapto-1-hexanol. On exposure to thrombin, the electrochemical impedance of the modified electrode increases gradually. Response is linear in the 0.1 pM to 5.0 nM thrombin concentration range, and the limit of detection is as low as 36 fM. The method is selective and capable of detecting thrombin in diluted human serum. In our perception, such a GCE modified with AgNP in a PDA matrix may be applied to many other analytes for which appropriate aptamers are available. Graphical abstractSchematic of an electrochemical aptasensor for sensitive and selective thrombin detection based on the use of a self-polymerized polydopamine film loaded with silver nanoparticles.

中文翻译：

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基于适配体的无标记凝血酶测定，基于使用掺入自聚合多巴胺的银纳米粒子

摘要作者描述了一种凝血酶电化学适体传感器，该传感器基于使用载有银纳米粒子 (PDA/AgNPs) 的聚多巴胺修饰的玻碳电极 (GCE)。AgNPs 的使用提高了薄膜的导电性并增加了 GCE 的表面积。PDA 通过自聚合沉积在 GCE 上，凝血酶结合适体通过一步反应接枝到 PDA 修饰的 GCE 上。残留的电极表面用 6-巯基-1-己醇封闭。在暴露于凝血酶时，修饰电极的电化学阻抗逐渐增加。响应在 0.1 pM 至 5.0 nM 凝血酶浓度范围内呈线性，检测限低至 36 fM。该方法具有选择性，能够检测稀释人血清中的凝血酶。在我们的认知中，这种在 PDA 基质中用 AgNP 修饰的 GCE 可以应用于许多其他有合适适体可用的分析物。基于使用负载有银纳米颗粒的自聚合聚多巴胺膜的用于灵敏和选择性凝血酶检测的电化学适体传感器的图形摘要示意图。