Characterizing functionalized electrode surfaces with unique spectroelectrochemical methods for biosensor development

使用独特的光谱电化学方法表征功能化电极表面，用于生物传感器的开发

• 批准号: RGPIN-2016-05528
• 负责人: Bizzotto, Dan
• 金额: $ 3.35万
• 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: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=615750
• 关键词: Characterizing; functionalized; electrode; surfaces; unique

Electrochemical processes form the basis of many new technologies (eg. batteries, fuel cells, solar cells) as well as approaches to bioanalytical sensing. The portability and small footprint of these sensors & their integration into smart phones will facilitate point of care analytical determinations, for which sensitive, specific and robust sensor development is required. Achieving this goal will require characterizing and controlling the functionalization of these surfaces which is at the core of this research program. We develop new methods to investigate these complex interfaces during electrochemical processes (in-situ). Electrochemical based biosensors rely on the modification of the electrode surface with biologically active species (eg lipids, nucleic acids or enzymes) that can specifically interact with compounds of interest in the sample, and then transduce this interaction into a signal that can be measured accurately. This requires a high level of control over the preparation of the sensor surface. A biosensor must have a sufficient number of probes on the surface which are accessible by the targets in solution so that when specifically interacting, will create a change in the measured signal. Controlling the probe density, probe distribution, reducing the non-specific interactions (noise) by controlling the surface structures will enable improvement of the functionalized surfaces with extension to development of new biosensor transduction motifs. Characterizing the electrochemical interface has been the focus of our research efforts for many years. We have developed a unique in-situ fluorescence microscopic method for analyzing these interfaces while controlling the electrochemical potential. This is accomplished by using a fluorophore labelled adsorbate. The fluorescence measured depends on the separation of the fluorophore from the electrode surface with fluorescence quenched when closer than 5nm. Our method enables a detailed understanding of the structure of these modified surfaces, from large scales (sub mm) to molecular sized regimes (10s of nm) and how this depends on the surface crystallography and the functionalization method (multiple step adsorption, co-adsorption, potential-controlled adsorption, chemical modification of the functionalized surface). We continue to advance our in-situ characterization method to include confocal microscopy with fluorescence lifetime imaging. These new analysis methods will be used in creating complex surfaces; from multi-component surfaces, to quantum dot decorated surfaces. Our long term goal is to devise methods for creating biosensor surfaces which are optimally functional guided by the use of advanced in-situ characterization techniques. This is the foundational principle which we will use to influence the creation of well defined biosensors and, more broadly all types of functionalized surfaces.

电化学过程构成了许多新技术的基础（例如，电池、燃料电池、太阳能电池）以及生物分析传感的方法。这些传感器的便携性和小尺寸以及它们与智能手机的集成将促进护理点分析测定，这需要灵敏、特异和强大的传感器开发。实现这一目标将需要表征和控制这些表面的功能化，这是本研究计划的核心。我们开发了新的方法来研究这些复杂的界面在电化学过程中（原位）。 基于电化学的生物传感器依赖于用生物活性物质（例如脂质、核酸或酶）修饰电极表面，所述生物活性物质可以与样品中的感兴趣的化合物特异性地相互作用，然后将这种相互作用转化为可以精确测量的信号。这需要对传感器表面的制备进行高度控制。生物传感器必须在表面上具有足够数量的探针，这些探针可被溶液中的靶接近，使得当特异性相互作用时，将在测量信号中产生变化。通过控制表面结构来控制探针密度、探针分布、减少非特异性相互作用（噪声）将能够改进功能化表面，并扩展到开发新的生物传感器转导基序。 表征电化学界面一直是我们多年来研究工作的重点。我们已经开发出一种独特的原位荧光显微镜方法来分析这些接口，同时控制的电化学电位。这是通过使用荧光团标记的吸附物来实现的。所测量的荧光取决于荧光团与电极表面的分离，当接近5 nm时荧光淬灭。我们的方法能够详细了解这些改性表面的结构，从大尺度（亚毫米）到分子大小的制度（10纳米），以及这如何取决于表面晶体学和功能化方法（多步吸附，共吸附，电位控制吸附，功能化表面的化学改性）。我们继续推进我们的原位表征方法，包括共聚焦显微镜与荧光寿命成像。这些新的分析方法将用于创建复杂的表面;从多组分表面到量子点装饰表面。我们的长期目标是设计方法，用于创建生物传感器表面的最佳功能的指导下使用先进的原位表征技术。这是我们将用来影响良好定义的生物传感器的创建，更广泛地说，所有类型的功能化表面的基本原则。