UPGRADE OF VARIABLE FREQUENCY PULSED EPR FACILITY

变频脉冲 EPR 设施升级

基本信息

批准号：
6877479
负责人：
JOHN H ENEMARK
金额：
$ 20.45万
依托单位：
UNIVERSITY OF ARIZONA
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-03-01 至 2007-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6877479
关键词：
biomedical equipment purchase cryostat electron spin resonance spectroscopy protein protein interaction

项目摘要

DESCRIPTION (provided by applicant): This proposal requests funding to substantially upgrade the variable frequency pulsed EPR Facility in the Department of Chemistry at the University of Arizona by acquiring a high field (1.99 Tesla) magnet system, including power supply, liquid helium cryostat with accessories and temperature controller, and a timing/ data acquistion module. Presently, a single 1.4 Tesla magnet system that is an integral part of the Bruker ESP300E X-band CW EPR spectrometer must also serve the requirements for the three unique broadband-pulsed EPR spectrometers that operate over the 2-8, 8-18 and 26-40 GHz ranges. This arrangement greatly limits the research output of the EPR Facility because only one type of EPR experiment can be running at any one time. In addition, the frequent changing among the spectrometers for the single available magnet system usurps valuable instrument time that could be used for productive research. Moreover, the 1.4 Tesla field of the existing magnet is too low to enable EPR signals with g < 2.0 to be studied by high resolution pulsed EPR techniques near 40 GHz. This high frequency range is essential for pulsed EPR studies of several of the biomolecules of the investigators of this proposal, including investigation of 14N, 15N interactions in heme proteins and Rieske proteins and 17-O in molybdenum enzymes, all of which have g-values spread below g=2. The requested 1.99 Tesla magnet system with power supply, liquid helium cryostat with accessories and temperature controller, and a timing/data acquisition module, will handle the ever increasing demands for experiments on metallobiomolecules using the existing 8-18 and 26-40 GHz pulsed broadband EPR spectrometers as well as provide increased access of users to the CW X-band and pulsed S/C band (2-8 GHz) spectrometers.

描述（由申请人提供）：该提案要求提供资金，通过购买高场（1.99 特斯拉）磁体系统，大幅升级亚利桑那大学化学系的变频脉冲 EPR 设施，包括电源、带有配件和温度控制器的液氦低温恒温器以及一个计时/数据采集模块。目前，作为布鲁克 ESP300E X 波段 CW EPR 光谱仪不可或缺的一部分的单个 1.4 特斯拉磁体系统还必须满足在 2-8、8-18 和 26 上运行的三种独特的宽带脉冲 EPR 光谱仪的要求。 -40 GHz 范围。这种安排极大地限制了 EPR 设施的研究成果，因为同一时间只能运行一种类型的 EPR 实验。此外，单个可用磁体系统的光谱仪之间的频繁更换占用了可用于富有成效的研究的宝贵仪器时间。此外，现有磁体的 1.4 特斯拉磁场太低，无法通过 40 GHz 附近的高分辨率脉冲 EPR 技术研究 g < 2.0 的 EPR 信号。这个高频范围对于本提案研究人员的几种生物分子的脉冲 EPR 研究至关重要，包括研究血红素蛋白和 Rieske 蛋白中的 14N、15N 相互作用以及钼酶中的 17-O，所有这些都具有 g 值分布低于 g=2。所要求的 1.99 特斯拉磁体系统（带电源）、液氦低温恒温器（带附件和温度控制器）以及定时/数据采集模块，将满足使用现有 8-18 和 26-40 GHz 脉冲宽带进行金属生物分子实验不断增长的需求EPR 光谱仪还增加了用户对 CW X 波段和脉冲 S/C 波段 (2-8 GHz) 光谱仪的访问。