AbstractGraphene oxide doped with nitrogen and sulfur was decorated with gold nanoparticles (AuNP-SN-GO) and applied as a substrate to modify a glassy carbon electrode (GCE). An aptamer against the model protein thrombin was self-assembled on the modified GCE which then was exposed to thrombin. Following aptamer-thrombin interaction, biotin-labeled DNA and aptamer 2 are immobilized on another AuNP-SN-GO hybrid and then are reacted with the thrombin/AuNP-SN-GO/GCE to form a sandwich. The enzyme label horseradish peroxidase (HRP) was then attached to the electrode by biotin–avidin interaction. HRP catalyzes the oxidation of hydroquinone by hydrogen peroxide. This generates a strong electrochemical signal that increases linearly with the logarithm of thrombin concentration in the range from 1.0 × 10−13 M to 1.0 × 10−8 M with a detection limit of 2.5 × 10−14 M (S/N = 3). The assay is highly selective. It provides a promising strategy for signal amplification. In our perception, it has a large potential for sensitive and selective detection of analytes for which appropriate aptamers are available. Graphic abstractA sandwich-type electrochemical aptasensor is fabricated for detection of thrombin using a glassy carbon electrode modified with nitrogen- and sulfur-doped graphene oxide and gold nanoparticles.

中文翻译：

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使用氮和硫掺杂的氧化石墨烯和金纳米粒子修饰的玻璃碳电极进行夹心电化学凝血酶测定

摘要 掺杂氮和硫的氧化石墨烯用金纳米粒子 (AuNP-SN-GO) 修饰，并作为基底修饰玻碳电极 (GCE)。针对模型蛋白凝血酶的适体在修饰的 GCE 上自组装，然后将其暴露于凝血酶。在适体-凝血酶相互作用之后，生物素标记的 DNA 和适体 2 被固定在另一个 AuNP-SN-GO 杂交体上，然后与凝血酶/AuNP-SN-GO/GCE 反应形成夹心。然后通过生物素-抗生物素蛋白相互作用将酶标记辣根过氧化物酶 (HRP) 连接到电极上。HRP 通过过氧化氢催化对苯二酚的氧化。这会产生强电化学信号，该信号随凝血酶浓度的对数在 1.0 × 10-13 M 至 1.0 × 10-8 M 范围内线性增加，检测限为 2。5 × 10−14 M (S/N = 3)。该测定具有高度选择性。它为信号放大提供了一种有前景的策略。在我们看来，它在灵敏和选择性检测分析物方面具有很大的潜力，可以使用合适的适配体。图形摘要制作夹心型电化学适体传感器，使用经氮和硫掺杂的氧化石墨烯和金纳米粒子修饰的玻璃碳电极检测凝血酶。