Rapid Scan Biomedical EPR Spectroscopy and Imaging

描述(申请人提供)：将开发一种新的、创新的电子顺磁共振(EPR)方法，用于活体光谱学、成像和生物医学研究。一个由工程师、研究科学家、临床医生和产业界组成的合作伙伴计划设计和建造运行在250 MHz和L频段(约1.2GHz)的快速扫描电子顺磁共振系统。重点是精心设计光谱仪系统，包括磁铁、扫描线圈、谐振器和数据采集，以优化体内光谱和低频成像的生理EPR信号采集，这些低频被认为是体内动物研究中穿透深度和信噪比之间的最佳折衷。快速扫描EPR涵盖了磁场扫描相对于弛豫时间较快的区域，这是一种新开发的介于连续波和脉冲EPR之间的中间区域。直接探测快速扫描EPR信号直接提供吸收线形，不需要高入射功率就能揭示电子自旋弛豫时间，并在快速衰减信号中提供准确的峰相对幅度。具体目标是：(1)在L波段(约1.2千兆赫)建立一台专用的快速扫描光谱仪，扫描频率优化，用于生物医学、活体和成像实验。(2)在250 MHz频率下，搭建了改进的谐振器、快速扫描线圈和驱动器，并优化了快速扫描电桥。(3)在丹佛大学建造一个250 MHz快速扫描电桥、谐振器和磁场扫描线圈单元，并将其安装在芝加哥大学生理学活体成像中心，在那里它将用于对动物肿瘤中的氧浓度进行成像。将比较传统的连续波成像、脉冲EPR成像和快速扫描成像在血氧测定和肿瘤学方面的优势。(4)设计、建造和测试用于250 MHz和L波段的快扫描信号采集和光谱信息后处理的硬件/软件系统。

DESCRIPTION (provided by applicant): A new and innovative electron paramagnetic resonance (EPR) methodology will be developed for in vivo spectroscopy, imaging and biomedical research. A partnership of engineers, research scientists, clinicians, and industry propose to design and build rapid-scan EPR systems operating at 250 MHz and at L-band (ca. 1.2 GHz). The emphasis is on careful engineering of the spectrometer systems, including magnet, scan coils, resonator, and data acquisition to optimize physiological EPR signal acquisition for in vivo spectroscopy and imaging at the low RF frequencies that are accepted as the best compromises between penetration depth and signal to noise for in vivo animal studies. Rapid-scan EPR encompasses the regime in which the magnetic field sweep is fast relative to relaxation times, which is a newly developed intermediate regime between CW and pulsed EPR. Direct-detection rapid-scan EPR signals provide the absorption lineshape directly, reveal electron spin relaxation times without requiring high incident power, and provide accurate relative amplitudes of peaks in rapidly decaying signals. The Specific Aims are: (1) Build a dedicated rapid-scan spectrometer at L-band (ca. 1.2 GHz) with scan rates optimized for biomedical, in vivo, and imaging experiments. (2) At 250 MHz build improved resonators, rapid-scan coils and drivers, and optimize the rapid-scan bridge. (3) Build a 250 MHz rapid-scan bridge, resonator, and magnetic field scan coil unit at the University of Denver and install it at the University of Chicago Center for In Vivo Imaging of Physiology, where it will be used to image oxygen concentrations in animal tumors. The benefits of traditional CW imaging, pulsed EPR imaging, and rapid-scan imaging for oximetry and oncology will be compared. (4) Design, build and test hardware/software systems for acquisition of the rapid-scan signal and post-processing of spectral information that will be used at 250 MHz and at L-band.