Non-resonance Electron Spin Imaging

非共振电子自旋成像

• 批准号: 10303578
• 负责人: Mark Tseytlin
• 金额: $ 21.9万
• 依托单位: WEST VIRGINIA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-15 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10303578
• 关键词: Acidity; Address; Algorithms; Amplifiers; Biomedical Engineering; Blood capillaries; Cell Nucleus; Chemicals; Clinical; Clinical Research; Clinical Sciences; Clinical Trials; Collaborations; Computer software; Data; Detection; Development; Devices; Electron Spin Resonance Spectroscopy; Electrons; Elementary Particles; Engineering; Environment; Equilibrium; Fourier Series; Frequencies; Functional Imaging; Future; Geometry; Goals; Heating; Human; Hydrogels; Image; Imaging Device; Imaging Phantoms; Imaging technology; Individual; Institutes; Laboratories; Lithium; Location; Magnetic Resonance; Magnetic Resonance Imaging; Malignant Neoplasms; Mathematics; Measurement; Measures; Medicine; Methodology; Methods; Modeling; Molecular; Noise; Organ Model; Oxidation-Reduction; Oxygen; Partial Pressure; Particulate; Pattern; Penetration; Periodicity; Phase; Physiologic pulse; Polymers; Radiation; Radio Waves; Relaxation; Reporter; Reporting; Reproducibility; Resolution; Rotation; Sampling; Scanning; Signal Transduction; Source; Sum; System; Technology; Testing; Time; Tissue Model; Tissues; Translational Research; Tumor Oxygenation; Universities; University of Virginia Cancer Center; Water; West Virginia; base; bioimaging; clinical application; college; design; detection method; detection sensitivity; detector; electrical property; experimental study; human model; human tissue; image reconstruction; imaging modality; imaging system; improved; innovation; invention; magnetic field; mechanical properties; member; nanosecond; new technology; novel; particle; preclinical study; quantum; radio frequency; rate of change; response; stem; tumor; vector; voltage

Project Summary /Abstract Traditional magnetic resonance imaging methods, such as MRI, use radiofrequency (RF) waves to manipulate the spin, a quantum-mechanical property of subatomic particles. These particles include various types of nuclei and the electron. Constant magnetic fields are used in experiments, the strength of which must match the RF to observe resonance phenomena. The spins are very sensitive reporters of their local molecular environment. They can report the concentration, dynamics, and interactions of the surrounding molecules. However, the current resonance approach has its limitations that stem from the use of radio waves. When RF propagates through the sample, only an infinitesimally small amount of power contributes to the observable signals. Most of the energy is absorbed by the imaged object. RF energy dissipates as heat. Associated with this very inefficient use of power are multiple problems such as sample heating, limited penetration depth, power saturation of signal amplifiers, spin system saturation (distorts data), and increased noise. These problems are especially critical for electron-based paramagnetic resonance imaging. An alternative to traditional EPR, RF-free non-resonance electron spin imaging (NESI) method is proposed. This technology overcomes the limitations associated with the use of RF power. The key concept behind NESI is relatively simple. In the traditional methods, RF is used to rotate spin magnetization relative to the constant magnetic field. In NESI, the magnetic field is rotated with respect to the magnetization vector. Both experiments measure the precession of the magnetization vector around the constant magnetic field. Several innovative mathematical and engineering solutions are proposed to transform the described above concept into a fully functional imaging system. The NESI instrument will be built and rigorously tested using a wide range of samples (phantoms) with pre-determined geometry. A several-fold increase in sensitivity is expected compared to the standard EPR imaging method when traditional classical detection methods are used. Recent developments of quantum sensing promise unprecedented sensitivity for the detection of electron spin signals. These novel technologies are incompatible with the traditional EPR. Several standard types of spin probes will be used to image oxygen partial pressure (pO2) and acidity (pH) distribution in these phantoms. In future studies, NESI will be used in pre-clinical and clinical studies. Imaging of chemical microenvironment in bio-printed tissue and organ models is another important application of this technology.

项目概要/摘要 传统的磁共振成像方法（例如 MRI）使用射频 (RF) 波来操纵 自旋，亚原子粒子的量子力学特性。这些粒子包括各种类型的原子核 和电子。实验中使用恒定磁场，其强度必须与射频相匹配 观察共振现象。自旋是其局部分子环境的非常敏感的报告者。 它们可以报告周围分子的浓度、动态和相互作用。然而， 目前的共振方法由于无线电波的使用而存在局限性。当射频传播时 通过样本，只有极小量的功率对可观测信号有贡献。大部分 能量被成像物体吸收。射频能量以热量的形式消散。与此相关的效率非常低 功率的使用存在多种问题，例如样品加热、有限的穿透深度、信号的功率饱和 放大器、自旋系统饱和（数据失真）和噪声增加。这些问题对于 基于电子的顺磁共振成像。传统 EPR 的替代品，无射频非共振 提出了电子自旋成像（NESI）方法。该技术克服了相关的限制 使用射频功率。 NESI 背后的关键概念相对简单。在传统方法中，射频用于 相对于恒定磁场旋转自旋磁化强度。在 NESI 中，磁场随着旋转 相对于磁化矢量。两个实验都测量磁化矢量的进动 围绕恒定磁场。提出了几种创新的数学和工程解决方案 将上述概念转化为功能齐全的成像系统。 NESI仪器将建成 并使用具有预定几何形状的各种样本（模型）进行严格测试。几倍 与传统经典 EPR 成像方法相比，预计灵敏度会有所提高 使用检测方法。量子传感的最新发展有望为传感器提供前所未有的灵敏度 电子自旋信号的检测。这些新技术与传统的 EPR 不兼容。 几种标准类型的旋转探针将用于对氧分压 (pO2) 和酸度 (pH) 进行成像 分布在这些幻象中。在未来的研究中，NESI将用于临床前和临床研究。成像 生物打印组织和器官模型中的化学微环境是该技术的另一个重要应用 技术。