In-situ study of electrochemical interfaces modified by adsorbed organic molecules; characterizing heterogeneous adsorbate coverage with application to biosensors

吸附有机分子修饰电化学界面的原位研究；

• 批准号: 203356-2011
• 负责人: Bizzotto, Dan
• 金额: $ 4.01万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=569935
• 关键词: situ; study; electrochemical; interfaces; modified

In-situ characterization of electrochemical surfaces modified by adsorbed organic molecules is accomplished using a number of different approaches. We have developed a unique method that combines fluorescence microscopy and electrochemistry. This method is proving useful for characterizing the heterogeneity of surface coating, enabling the study of these surfaces with more detail thereby raising some important questions. The creation of advanced biosensors relies on the modification of surfaces to provide a functional interface that can sense the analyte in solution. A number of interesting motifs have been developed that rely upon the orientation of the adsorbed molecules on the sensor surface. These molecules (eg DNA) can include redox active moieties that provide a simple electrochemical signal (current) that can be used for signal transduction. In some cases, the current decreases upon binding, and this has been observed in buffers and complex media. Recent studies of the DNA modified gold surface with our in-situ fluorescence microscopic method has revealed that these surface, created following current literature procedures, are not homogeneous and are, in fact quite heterogeneous. This surprising result has resulted in a number of questions that this research proposal aims to answer. Are these surfaces as presented in simplified cartoons? Does our method highlight these imperfections, something that is hard to determine using the current analytical methods? Can we change the procedures used to make these sensors to eliminate or minimize these undesirable features? In collaboration with two electrochemical research groups in Europe, we will expand the types of molecules that we will assemble onto the electrode surface (aptamers, peptides, DNA). We aim to understand these sensor surfaces and with our unique in-situ characterization tool, determine the characteristics of the system that contribute to these heterogeneous regions, and assess the impact on sensor response. We also intend to use this method to continue our studies into creating a model of a biomembrane supported on an electrode, and to investigate the nature of the forces that govern the movement of molecules that are electrochemically desorbed.

使用许多不同的方法可以对吸附有机分子改性的电化学表面进行原位表征。我们开发了一种结合荧光显微镜和电化学的独特方法。事实证明，这种方法对于表征表面涂层的异质性非常有用，可以更详细地研究这些表面，从而提出一些重要的问题。 先进生物传感器的创建依赖于表面的修饰，以提供可以感知溶液中分析物的功能界面。已经开发出许多有趣的图案，这些图案依赖于传感器表面上吸附分子的方向。这些分子（例如DNA）可包括氧化还原活性部分，其提供可用于信号转导的简单电化学信号（电流）。在某些情况下，结合时电流会降低，这已在缓冲液和复杂介质中观察到。最近使用我们的原位荧光显微方法对 DNA 修饰的金表面进行的研究表明，按照当前文献程序创建的这些表面不是均质的，实际上是相当异质的。这一令人惊讶的结果引发了本研究计划旨在回答的许多问题。这些表面是简化漫画中所呈现的吗？我们的方法是否突出了这些缺陷，而使用当前的分析方法很难确定这些缺陷？我们能否改变制造这些传感器的程序，以消除或最大限度地减少这些不良特征？我们将与欧洲的两个电化学研究小组合作，扩大组装到电极表面的分子类型（适体、肽、DNA）。我们的目标是了解这些传感器表面，并利用我们独特的原位表征工具，确定导致这些异质区域的系统特征，并评估对传感器响应的影响。我们还打算使用这种方法继续研究创建电极支撑的生物膜模型，并研究控制电化学解吸分子运动的力的性质。