MRI: Development of an Optical Super-resolution Instrument for Measuring Concentration Profiles and Diffusion Dynamics in Thin Films

这是一个开发一种仪器的项目，它将使材料界面的新发现成为可能。大量科学和技术上重要的过程发生在固体和液体之间的界面上。例如，一种材料与另一种材料的粘附，医院表面的清洁和消毒，电池的充电以及油的回收都是发生在固体和液体之间的界面上的过程。该项目将开发一种新型显微镜，以比以前更快的速度更详细地揭示这些界面的微观细节。这种显微镜可以在百万分之一秒内观察到结构的变化。如此高的速度需要帮助研究人员了解和工程师改进工业和医疗流程，从而提高国家的生产力和福祉。这个项目的一个组成部分是培养下一代的科学家和工程师。该项目将提供以下方面的培训：(1)女高中生，(2)本科生，(3)攻读博士学位的学生。这些学生将继续为高科技行业的工作以及未来一代的研究人员提供训练有素的劳动力。本项目开发的仪器将实现一种RESOLFT（可逆饱和光学荧光转换）光学超分辨率显微镜技术，适用于研究固体-液体界面荧光标记物种的分布和动力学。具体来说，该仪器将通过聚焦在界面上的两束反向传播光束的干涉来优化轴向分辨率，并利用基态损耗（GSD）模式。它将使轴向分辨率高达10纳米，同时研究过程的时间演变低至0.25微秒，同时保持标准共聚焦显微镜的横向分辨率。高分辨率分析和快速时间分辨率的结合使仪器能够解决材料科学，表面科学，电化学，聚合物科学和邻近领域的一系列未满足的表征需求。可以用该仪器研究的系统示例包括聚合物和离子的空间分布，这对抗菌性能至关重要；生物分子和界面之间的相互作用，如聚合物与细胞膜之间的相互作用；纳米粒子在表面上自组装的动力学，必须理解它才能在实际应用中利用自组装；以及电极附近离子传输的动力学。这对电池和其他电化学系统非常有意义。该奖项反映了美国国家科学基金会的法定使命，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。

This is a project to develop an instrument that will enable new discoveries about material interfaces. A vast range of scientifically and technologically important processes occur at interfaces between solids and liquids. For example, the adhesion of one material to another, the cleaning and disinfection of hospital surfaces, the charging of batteries, and the recovery of oil are all processes that occur at interfaces between solids and liquids. The project will develop a new type of microscopy that will reveal the microscopic details of these interfaces in greater detail and at much greater speed than previously obtainable. The microscope will make it possible to observe changes in structure as quickly as one-millionth of a second. Such high speeds are required to help researchers understand and engineers improve industrial and medical processes that increase the nation’s productivity and well-being. An integral part of the project will be to train future generations of scientists and engineers. The project will provide training in the following areas (1) female high school students, (2) undergraduate students, and (3) students studying to complete Ph.D. programs. Such students go on to provide the workforce that is trained for work in high-tech industries as well as the future generation of researchers. The instrument developed in this project will implement a RESOLFT (Reversible Saturable Optical Fluorescence Transitions) optical super-resolution microscopy technique adapted to study the distribution and dynamics of fluorescently labelled species at solid–liquid interfaces. Specifically, the instrument will be optimized for the highest possible axial resolution through the interference of two counterpropagating beams focused at the interface, and make use of the Ground State Depletion (GSD) modality. It will enable axial resolution as high as 10 nm while studying time-evolution of processes down to 0.25 microseconds, all while maintaining lateral resolution of a standard confocal microscope. The combination of high-resolution profiling and fast time resolution allows the instrument to address a range of unmet characterization needs in materials science, surface science, electrochemistry, polymer science, and adjacent fields. Examples of systems that could be studied with the instrument include spatial distribution of polymers and ions, which is crucial for antimicrobial performance, interactions between biomolecules and interfaces, such as polymers with cell membranes, the dynamics of nanoparticle self-assembly on surfaces, which must be understood to harness self-assembly for practical applications, and dynamics of ion transport near electrodes, which is of great interest in batteries and other electrochemical systems.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.