MRI: Acquisition of In-Situ Electron Microscopy Instrumentation to Monitor Kinetic Processes in Complex Materials and Molecules

MRI：获取原位电子显微镜仪器来监测复杂材料和分子的动力学过程

• 批准号: 1828628
• 负责人: Matthew Helgeson
• 金额: $ 70万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-10-01 至 2021-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1828628&HistoricalAwards=false
• 关键词: MRI; Acquisition; Situ; Electron; Microscopy

Although nanometer-scale kinetic and dynamic processes in liquids are a unifying feature of industrial chemistry, advanced materials and biology, our measurement capabilities to directly visualize and quantify these processes are usually limited to large objects and slow behavior. Recent technological advances in electron microscopy instrumentation, including ambient liquid sample holders and fast cameras that detect electrons directly, have overcome these limitations to provide a previously unobtainable feat - direct, high-frame rate and high-spatial-resolution video electron microscopy of fluids, soft materials and interfaces between different materials. This project involves the acquisition of these combined instrumental capabilities for incorporation with a state-of-the-art electron microscope at the University of California, Santa Barbara. Combined with advanced dynamic image analysis methods, these new capabilities provide a foundational tool for fundamental studies of kinetic and dynamic processes in liquids at the single-molecule and single-particle level and establish core expertise in dynamic liquid nanostructure visualization on the campus. The new capabilities also inspire a new generation of researchers to push the boundaries of liquid electron microscopy and the science it enables.This Major Research Instrumentation grant allows acquisition of an in-situ liquid cell holder with on-chip temperature, flow and electrochemical control, together with a third-generation direct electron detector. Combined with a newly installed state-of-the-art electron microscope, ThermoFisher/FEI Talos F200X G2, this acquisition allows for direct visualization of liquids with high spatial (0.2 nm) and temporal (above 1 kHz) resolution under a range of ambient conditions and applied electrical fields through on-chip high-field circuitry on the liquid cell. The ability to modify the sample-cell interface in the liquid cell and use flow to rapidly exchange fluids help realize unprecedented experiments to directly observe a wide range of physicochemical processes in unconfined, nano-confined and interfacial fluids including phase transformations, molecular motions and interactions, as well as chemical and electrochemical reactions. The large data sets from these experiments benefit from a suite of newly developed video microscopy analysis tools to resolve and quantify the complex and often subtle features of kinetic and dynamic processes in nanoscale liquids. These powerful new tools are deployed to address some of the most impenetrable and vexing scientific challenges in materials science and structural biology, including (i) metastable and unstable phase separation during nanoconfinement and nanomaterial synthesis, (ii) single-molecule electrochemical characterization of catalytic materials, and (iii) fundamental mechanisms of aggregation and coacervation in disordered biomolecules.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.

尽管纳米尺度的液体动力学和动力学过程是工业化学、先进材料和生物学的统一特征，但我们直接可视化和量化这些过程的测量能力通常仅限于大型物体和缓慢的行为。电子显微镜仪器的最新技术进步，包括环境液体样品夹和直接探测电子的快速照相机，已经克服了这些限制，提供了以前无法实现的壮举--对流体、软材料和不同材料之间的界面进行直接、高帧速率和高空间分辨率的视频电子显微镜。该项目涉及收购这些组合仪器能力，以便与加州大学圣巴巴拉分校最先进的电子显微镜相结合。与先进的动态图像分析方法相结合，这些新功能为单分子和单颗粒水平的液体动力学和动态过程的基础研究提供了基础工具，并在校园内建立了动态液体纳米结构可视化的核心专业知识。新的能力还激励新一代研究人员推动液体电子显微镜及其实现的科学的边界。这项重大研究仪器拨款允许获得具有芯片上温度、流量和电化学控制的现场液体电池支架，以及第三代直接电子检测器。与最新安装的最先进的电子显微镜ThermoFisher/FEI Talos F200X G2相结合，通过液池上的芯片上高场电路，可以在各种环境条件和施加电场的情况下，以高空间(0.2 nm)和时间(高于1 kHz)的分辨率直接显示液体。能够改变液池中的样品-细胞界面并利用流动快速交换流体的能力有助于实现前所未有的实验，以直接观察无限制、纳米限制和界面流体中的广泛物理化学过程，包括相变、分子运动和相互作用以及化学反应和电化学反应。这些实验的大型数据集得益于一套新开发的视频显微镜分析工具，用于解析和量化纳米级液体中动力学和动态过程的复杂且往往微妙的特征。这些强大的新工具被用于解决材料科学和结构生物学中一些最棘手和最棘手的科学挑战，包括(I)纳米限制和纳米材料合成过程中的亚稳态和不稳定相分离，(Ii)催化材料的单分子电化学表征，以及(Iii)无序生物分子中聚集和凝聚的基本机制。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。