Single Molecule Fluorescent Indicators for Gas-Phase Sensing of Metals

用于金属气相传感的单分子荧光指示剂

• 批准号: 2004111
• 负责人: Frank Foss
• 金额: $ 42万
• 依托单位: University of Texas at Arlington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2004111&HistoricalAwards=false
• 关键词: Single; Molecule; Fluorescent; Indicators; Gas

Heavy metals are continuously introduced into the atmosphere by natural and human activity, a process that endangers the health and well-being of the public and the environment. Current methods for measuring the presence of harmful metals in materials in the atmosphere require time-consuming processes to concentrate metal targets, as well as complicated sample preparation methods for the intricate analyses. A major limitation of these existing methods is that atmospheric materials have to be placed in water or other solvents to be analyzed. Significant advances in rapid, heavy metal detection could occur by direct light-based measurement of metals present in gases at the point of their generation (prior to entering the atmosphere). However, our understanding of how to detect heavy metals in gases using fluorescent light-based sensors is hindered by the inability to study molecular-level interactions between a metal of interest and fluorescent receptors that report metal presence. Single-molecule fluorescence imaging technologies may enhance the design of gas-phase sensors for heavy metal ions. These enabling technologies have the potential to offer early-stage detection of metal contamination to help prevent significant harm to human health and the environment. Recent advances in the single-entity fluorescence imaging of ions from gases have been made at the University of Texas at Arlington. This project brings together a unique combination of techniques to create sensitive gas-phase sensors that measure toxic heavy metals, with a focus on lead, mercury, and cadmium as some of the most harmful heavy metals. Graduate, undergraduate, and high school researchers in Dr. Frank Foss Jr.’s laboratory design and make sophisticated fluorescence imaging materials that are placed on optical surfaces. These materials can then be used to assess presence of metals in the atmosphere. The research and training environment allows for learning about fundamentals of molecule-metal chemistry, photophysics, and cutting-edge approaches to making molecules, as well as scientific literacy and teamwork skills that propel the careers of the scientists in training.With this award, the Chemical Measurement and Imaging Program is funding Dr. Frank Foss Jr. at the University of Texas at Arlington to synthesize and study hybrid materials that directly investigate the fundamentals of heavy metal ion capture, surface dynamics, and fluorescence at gas-solid interfaces. Fundamental kinetic and thermodynamic properties are complicated by the seemingly irreversible nature of analyte binding in solvent-less environments and limited by methods that investigate bulk properties of ions on surfaces, rather than molecular properties. Turn-on, single-molecule fluorescence imaging (SMFI) methods have revolutionized our understanding of biomolecular and catalytic events at the molecular level in solution. Preparation of new turn-on fluorescence sensors containing rigid ion-selective receptors with solid-state functioning fluorophores provide SMFI materials that can be incorporated into self-assembled monolayers at gas-solid interfaces. To enhance ion binding selectivity, SMFI-SAMs are modified with solid electrolyte-inspired ion transport materials. Ion sensing and mobility measurements in SMFI-SE-SAMs are studied by microscopy and supported by computational experiments to enhance gas-phase sensing technologies and provide new tools for investigating surface design and function. These studies provide the molecular scale insight necessary for attaining ultra-low levels of detection by rapid gas sensitive fluorescent measurements. This interdisciplinary collaborative project brings together new materials with recently developed microscopy techniques to evaluate the measurement and selectivity of these devices to detect toxic heavy metal ions directly from the gas phase.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

重金属通过自然和人类活动不断进入大气，这一过程危及公众和环境的健康和福祉。目前测量大气中有害金属的方法需要耗时的过程来浓缩金属目标，以及复杂的样品制备方法来进行复杂的分析。这些现有方法的一个主要限制是，大气物质必须放置在水或其他溶剂中进行分析。在气体产生时（进入大气之前），通过对气体中存在的金属进行直接的光基测量，可以在快速重金属检测方面取得重大进展。然而，我们对如何使用基于荧光的传感器检测气体中重金属的理解受到无法研究感兴趣的金属和报告金属存在的荧光受体之间分子水平相互作用的阻碍。单分子荧光成像技术可以提高重金属离子气相传感器的设计。这些使能技术有可能提供金属污染的早期检测，以帮助防止对人类健康和环境的重大危害。最近，在阿灵顿的得克萨斯大学，在气体离子的单实体荧光成像方面取得了进展。该项目汇集了独特的技术组合，以创建测量有毒重金属的灵敏气相传感器，重点关注铅，汞和镉等最有害的重金属。研究生，本科生和高中研究人员在博士弗兰克福斯小'。该实验室设计并制造放置在光学表面上的复杂荧光成像材料。 然后这些材料可用于评估大气中金属的存在。研究和培训环境允许学习分子-金属化学、电子物理学和尖端分子制造方法的基础知识，以及推动科学家职业生涯的科学素养和团队合作技能。通过该奖项，化学测量和成像计划资助Frank Foss Jr.博士。在得克萨斯大学阿灵顿的合成和研究混合材料，直接调查的重金属离子捕获，表面动力学，和荧光在气固界面的基本原理。基本的动力学和热力学性质是复杂的分析物结合在无溶剂的环境中的看似不可逆的性质和有限的方法，调查表面上的离子的本体性质，而不是分子性质。开启，单分子荧光成像（SMFI）方法已经彻底改变了我们对溶液中分子水平的生物分子和催化事件的理解。制备含有具有固态功能荧光团的刚性离子选择性受体的新的开启荧光传感器提供了可以在气-固界面处并入自组装单层的SMI材料。为了增强离子结合选择性，SMFI-SAM用固体电解质激发的离子传输材料改性。SMFI-SE-SAMs中的离子传感和迁移率测量通过显微镜进行研究，并通过计算实验来支持，以增强气相传感技术，并为研究表面设计和功能提供新的工具。这些研究提供了通过快速气敏荧光测量实现超低水平检测所需的分子尺度洞察力。这个跨学科的合作项目将新材料与最新开发的显微镜技术结合在一起，以评估这些设备的测量和选择性，从而直接从气相中检测有毒重金属离子。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。