RELAXATION TIME MEASUREMT OF NITROXIDE PROBES FOR SCANNED-PROBE MAGNETIC FORCE

扫描探针磁力氮氧化物探针弛豫时间测量

• 批准号: 8364049
• 负责人: PETER P BORBAT
• 金额: $ 0.14万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8364049
• 关键词: Caliber; Custom; Detection; Electron Spin Resonance Spectroscopy; Film; Frequencies; Funding; Grant; Image; Individual; Magnetic Resonance; Magnetism; National Center for Research Resources; Nickel; Phase; Principal Investigator; Relaxation; Research; Research Infrastructure; Resources; Sampling; Scanning; Source; Spin Labels; Technology; Time; United States National Institutes of Health; cantilever; cost; macromolecule; novel strategies; research study; theories

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. John Marohn has developed an approach that extends the applicability of ultrasensitive force gradient detection of magnetic resonance to samples with spin-lattice relaxation times (T1) as short as a single cantilever period. The generality of the approach, which relies on detecting either cantilever frequency or phase, was demonstrated by detecting electron spin resonance from a T1 = 1 ms nitroxide spin probe (TEMPAMINE) in a thin film at 4.2 K and 0.6 T. A custom fabricated cantilever with a 4 Mu m diameter nickel tip, was used to achieve a magnetic resonance sensitivity of 410 Bohr magnetons in a 1 Hz bandwidth. The theory underlying this experiment quantitatively predicts both the lineshape and the magnitude of the observed cantilever frequency shift as a function of field and cantilever-sample separation. The new approach has a number of advantages that make it well suited for magnetic resonance detection and imaging of nitroxide spin labels in an individual macromolecule at single-spin sensitivity

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的主要研究者可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 John Marohn 开发了一种方法，将磁共振超灵敏​​力梯度检测的适用性扩展到自旋晶格弛豫时间 (T1) 短至单个悬臂梁周期的样品。该方法的通用性依赖于检测悬臂梁频率或相位，通过在 4.2 K 和 0.6 T 下检测薄膜中 T1 = 1 ms 硝基氧自旋探针 (TEMPAMINE) 的电子自旋共振来证明。使用带有 4 μm 直径镍尖的定制悬臂梁，可在 1 Hz 频率下实现 410 个玻尔磁子的磁共振灵敏度 带宽。该实验的理论定量预测了观察到的悬臂频移的线形和幅度，作为场和悬臂样品分离的函数。新方法具有许多优点，使其非常适合在单自旋灵敏度下对单个大分子中的硝基氧自旋标记进行磁共振检测和成像