HIGH FREQUENCY EPR OF VIABLE BIOLOGICAL SYSTEMS

可行生物系统的高频 EPR

• 批准号: 6120643
• 负责人: ALEX I. SMIRNOV
• 金额: $ 2.16万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-04-15 至 1999-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6120643
• 关键词: animal tissue; biological products; biomedical resource

Over the past decade it has been shown that very high frequency (VHF) EPR offers great advantages in many types of experiments. However, to date we have seen no documented attempts to apply this technique to viable biological systems. The reasons for this are both technical and psychological: the sample volume at W-band (95 GHz) could be 1000-fold smaller than at conventional X-band, and microwave losses are somewhat higher. In the present work we demonstrate the prospects for VHF EPR in cellular studies. The VHF EPR has a better absolute point sensitivity, which is essentially needed in studies of small objects (like a single cell) or surfaces, including cellular membranes. The better g-value resolution offered by VHF EPR enables one to separate spectroscopically different kinds of nitroxide radicals within the same system, or radicals in different molecular environments (e.g. to distinguish more clearly between nitroxide molecules dissolved in lipids, membranes, and aqueous phase of the cell). Another possible application of VHF EPR spectroscopy and imaging is in cryobiology, where nitroxide spin probes could be used to follow redistribution processes in cells during freezing.

在过去的十年中，人们已经表明了很高的​​频率 （VHF）EPR在许多类型的实验中都具有很大的优势。 但是，到目前为止，我们已经看到没有记录在应用此应用的尝试 可行生物系统的技术。 原因是 技术和心理：W波段的样本量（95 GHz） 可能比常规X波段和微波炉小1000倍 损失更高。 在目前的工作中，我们证明了 VHF EPR在细胞研究中的前景。 VHF EPR更好 绝对点灵敏度，这在研究中基本上需要 小物体（如单个单元格）或表面，包括细胞 膜。 VHF EPR提供的更好的G值分辨率启用 一个分离光谱上不同种类的硝酸 同一系统内的自由基，或不同分子中的自由基 环境（例如，更清楚地区分氮氧化物 溶解在脂质，膜和水相中的分子 单元格）。 VHF EPR光谱和 成像是在冷冻生物学中，可以使用氮氧化物旋转探针 在冷冻过程中遵循细胞中的重新分布过程。