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.

项目摘要/摘要