Highly Sensitive Planar Anapole Microresonators for Electron Paramagnetic Resonance Spectroscopy of Submicroliter/Submicromolar Samples

用于亚微升/亚微摩尔样品电子顺磁共振波谱分析的高灵敏度平面 Anapole 微谐振器

• 批准号: 9978253
• 负责人: PHYLLIS R ROBINSON
• 金额: $ 21.13万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE COUNTY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-08 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9978253
• 关键词: Affect; Biological; Biomedical Research; Coupled; Coupling; Crystallization; Detection; Devices; Dimensions; Disease; Drug Design; Drug Targeting; Electron Spin Resonance Spectroscopy; Elements; Film; Frequencies; G-Protein-Coupled Receptors; GTP-Binding Protein alpha Subunits, Gs; Geometry; Goals; Home environment; Laboratory Research; Lead; Magnetism; Membrane Proteins; Methodology; Microfluidic Microchips; Microfluidics; Miniaturization; Modeling; Molecular Conformation; NMR Spectroscopy; Peptides; Performance; Pharmaceutical Preparations; Physiologic pulse; Physiological; Polymers; Proteins; Radiation; Reporting; Sampling; Series; Site; Source; Spin Labels; Structure; Structure-Activity Relationship; System; Techniques; Temperature; Thinness; aqueous; base; biomacromolecule; cold temperature; cryogenics; design; experimental study; improved; innovation; instrument; instrumentation; magnetic field; melanopsin; microwave electromagnetic radiation; nanofabrication; nanolitre; nanolitre scale; nitroxyl; novel; operation; performance tests; protein folding; public health relevance; receptor; simulation; structural biology

Abstract: Electron paramagnetic resonance (EPR) spectroscopy can provide information about the structure and dynamics of biomacromolecules in physiologically relevant conditions. Its inherently high sensitivity is still inadequate for some mass-limited samples -- for example, membrane proteins -- which are notoriously difficult to express, purify, and crystallize. This project aims to decrease the limit of detection for inductive-detection EPR spectroscopy at room temperature, so that low-yield biomacromolecular samples can be studied under physiologically relevant conditions. To achieve this objective, we will use a novel resonator design that bridges the gap between planar microresonators and conventional cavity resonators. Our novel planar inverse anapole microresonator design provides nanoliter active volumes combined with high quality factors, providing a projected improvement of two orders of magnitude in sensitivity at room temperature. Our first aim is to design and fabricate microresonators for operation at 9 GHz and 34 GHz. First, we will carry out finite element simulations of the field distributions and reflection coefficients for resonators coupled to waveguides. Based on these results, we will optimize the device geometry and dimensions to obtain nanoliter magnetic-field hotspots and high quality-factors. We will fabricate these optimized resonators at the NIST Nanofabrication facility. Next, we will characterize the microresonators and integrate them into a commercial 9 GHz and home-built 34 GHz EPR spectrometer. Our second aim is to demonstrate the viability of these resonators for structural biology EPR spectroscopy experiments. To do this, we will first design and fabricate microfluidic devices capable of localizing nanoliter sample volumes in the magnetic hotspot volume of the microresonator. To validate the device performance, we will use a concentration series of spin-labeled peptides. Finally, to demonstrate applicability to a biomacromolecular sample, we will study the Gprotein coupled receptor melanopsin. If successfully implemented, this resonator design will achieve an unprecedented sensitivity for EPR spectroscopy, broadening its applicability to low-yield biomacromolecular samples whose structures are currently poorly understood.

摘要：电子顺磁共振（EPR）光谱可以提供有关 生物学与生理相关条件下的生物大分子的结构和动力学。它固有的高 对于某些质量有限的样品（例如，膜蛋白），灵敏度仍然不足 众所周知，很难表达，净化和结晶。该项目旨在降低 在室温下检测电感检测EPR光谱的检测，因此低收益 可以在生理上相关的条件下研究生物焦分子样品。实现这一目标 目的，我们将使用一种新颖的谐振器设计，该设计弥合了平面微孔子和 常规的空腔谐振器。我们新颖的平面逆氨基烷微孔子设计提供 纳米仪的主动量与高质量的因素相结合，预计改善了两个 在室温下灵敏度的数量级。我们的第一个目的是设计和制造 在9 GHz和34 GHz的操作微孔子。首先，我们将进行有限元模拟 谐振器的场分布和反射系数与波导结合。基于这些 结果，我们将优化设备的几何形状和尺寸以获得纳米级磁场热点 和高质量的因子。我们将在NIST纳米制造中制造这些优化的谐振器 设施。接下来，我们将描述微孔子并将其集成到商业9 GHz中，并将其集成 家庭建造的34 GHz EPR光谱仪。我们的第二个目的是证明这些谐振器的生存能力 用于结构生物学EPR光谱实验。为此，我们将首先设计和制造 微流体设备能够在磁性热点体积中定位纳米尺量的微流体设备 微孔子。为了验证设备性能，我们将使用一系列旋转标签的浓度系列 肽。最后，为了证明适用于生物分子样品，我们将研究GPROTEIN 耦合受体黑素蛋白。如果成功实施，此谐振器设计将实现 对EPR光谱的空前灵敏度，扩大了其对低收益的适用性 目前结构较少了解的生物焦分子样品。