Control of Potential Response to Small Biomolecules with Electrochemically Grafted Aryl-Based Monolayer in Field-Effect Transistor-Based Sensors
Control of Potential Response to Small Biomolecules with Electrochemically Grafted Aryl-Based Monolayer in Field-Effect Transistor-Based Sensors
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DOI：
10.1021/acs.langmuir.9b00085
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发表时间：
2019-03-12
期刊：
影响因子：
3.9
通讯作者：
Sakata, Toshiya
中科院分区：
文献类型：
--
作者：
Himori, Shogo;Nishitani, Shoichi;Sakata, Toshiya
在这篇论文中，我们展示了通过重氮化学电接枝单分子膜来控制场效应晶体管(FET)传感器的电位响应。用循环伏安法(CV)将4-硝基苯重氮盐电接枝到扩展金栅FET(EG-Au-FET)上，得到单分子膜或多层膜。特别是，随着循环伏安循环次数的增加，芳基衍生物单分子膜在金栅电极上的表面覆盖率逐渐增加。在这里，金表现出很强的催化作用，导致有机化合物的氧化。尿酸作为一种小分子生物分子用于干扰。接枝单分子层的表面覆盖率越高，EG-Au-FET的电势响应越小，这是因为尿酸与金栅表面的氧化还原反应被抑制了。另一方面，芳基衍生物多层膜对电位响应的抑制作用小于单分子膜，因为电生的芳基自由基不与Au表面反应，而是与接枝物种反应，导致接枝的芳基分子中Au表面裸露部分。因此，基于这种通过重氮化学电接枝的单层膜的平台适合于基于生物样品中低分子生物分子的干扰来控制电位响应。
In this paper, we demonstrate the use of a monolayer film electrografted via diazonium chemistry for controlling the potential response of a field-effect transistor (FET)-based sensor. 4-Nitro-benzenediazonium salt is electrografted on an extended-Au-gate FET (EG-Au-FET) with or without using a radical scavenger by cyclic voltammetry (CV), resulting in the formation of a monolayer or multilayer. In particular, the surface coverage of the aryl-derivative monolayer on the Au gate electrode gradually increases with increasing number of potential cycles in CV. Here, Au exhibits a strong catalytic action, resulting in the oxidation of organic compounds. Uric acid is used as a low-molecular-weight biomolecule for interference. The denser the surface coverage of the grafted monolayer, the smaller the potential response of the EG-Au-FET because the redox reaction of uric acid with the Au gate surface is suppressed. On the other hand, the effect of the aryl-derivative multilayer on the suppression of the potential response was smaller than that of the monolayer because the electrogenerated aryl radicals did not react with the Au surface but with the grafted species, resulting in an exposed part of the Au surface among the grafted aryl molecules. Thus, a platform based on such a monolayer film electrografted via diazonium chemistry is suitable for controlling the potential response based on the interference of low-molecular-weight biomolecules in biosamples.