SCANNING TRANSMISSION ELECTRON MICROSCOPE +XRAY ANALYZER

扫描透射电子显微镜X射线分析仪

• 批准号: 3520574
• 负责人: Meredith Bond
• 金额: $ 27.5万
• 依托单位: CLEVELAND CLINIC FOUNDATION
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-05-10 至 1991-05-09
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3520574
• 关键词: biomedical equipment purchase; biomedical equipment resource; electron probe spectrometry; scanning electron microscopy

The Research Institute of the Cleveland Clinic Foundation is a rapidly expanding research center with a growing core of NIH-funded investigators. In order to fulfill the urgent instrumentation needs of the Institute, we are requesting an analytical scanning transmission electron microscope, the Philips CM12/STEM, interfaced with an X-ray microanalysis system, the LINK AN10000. The Philips microscope was chosen based on its excellent vacuum system, ability to interface with a horizontal X-ray detector with a 20o take-off angle, ease of use in both TEM and STEM modes and simplified operating consoles. The principle reason that the LINK system was chosen was the exceptionally high resolution of the X-ray detector as well as the suitability of the analytical programs for on-line elemental quantitation of biological samples. Three out of eight of the primary users are investigating subcellular distribution of Ca2+ and other elements: during the cardiac cycle in hamster heart in vivo (Dr Bond), in axonal preparations from sciatic nerve in response to parathyroid hormone stimulation (Dr Breuer) and following exposure to oxidized low density lipoprotein during the S phase of the cell cycle in cultured human fibroblasts (Dr Chisolm). Each of these investigators requires the use of the X-ray microanalysis system, as well as the extended capabilities of the STEM, which will provide the opportunity to carry out X-ray mapping, in addition to spectral collection with a stationary probe in TEM. Dr Harasaki is a fourth user of X-ray microanalysis who will investigate elemental localization on the surfaces of bioprosthetic heart valves. Drs Hoff and Cole are investigating receptor-mediated endocytosis of low density lipoproteins, using colloidal gold labelled specimens, in some instances on specimens of low contrast. These investigators, together with Dr Shainoff, who is studying the role of fibrinogen in platelet aggregation, will greatly benefit from the enhanced image contrast available in STEM. Dr Block uses colloidal-gold labelled markers to examine the subcellular localization of the hypothalamic Angiotensin II system and Dr Jacobsen investigates the role of cobalamin-binding proteins in the enterohepatic circulation, using colloidal gold tagged antibodies to cabalamin-binding proteins. These two investigators will primarily operate the microscope in conventional transmission mode, but may also benefit from the STEM and from the particle counting software provided by LINK. The projects of Drs Hoff and cole, as well as Dr Harasaki, will also require the increased resolution provided in secondary and backscattered images that can be obtained in STEM (compared with SEM). In this mode of operation, they will utilize the image mixing capabilities of the microscope. In summary, a versatile, state-of-the-art analytical scanning transmission electron microscope will greatly benefit a large number of users in the Research Institute and will fulfill a much needed role as an Institute-wide facility.

克利夫兰临床基金会研究所是一个迅速 扩大研究中心，NIH资助的研究人员的核心不断增加。 为了满足研究所的迫切仪器需求，我们 正在要求一种分析型扫描电子显微镜， 飞利浦CM12/STEM，与X射线显微分析系统接口，LINK 10000元。选择飞利浦显微镜是因为它具有极好的真空性能 系统，能够与具有200o的水平X射线探测器对接 起飞角度，在瞬变电磁模式和STEM模式下都易于使用，并简化了 操作控制台。选择联系制的主要原因 是X射线探测器异常高的分辨率，以及 在线元素定量分析程序的适用性 生物样本。八分之三的主要用户是 研究钙离子和其他元素的亚细胞分布： 活体仓鼠心脏的心动周期(邦德博士)，轴突 坐骨神经制剂对甲状旁腺激素的反应 刺激(Breuer博士)和暴露在氧化低密度下 培养的人细胞周期中S期脂蛋白的变化 成纤维细胞(Chsolm博士)。这些调查人员中的每一个都需要使用 X射线显微分析系统，以及 STEM，这将提供进行X射线测绘的机会，在 除了在透射电子显微镜中使用固定探头进行光谱采集。博士 原崎是第四位使用X射线显微分析的人，他将研究 生物瓣膜表面的元素定位。DRS 霍夫和科尔正在研究受体介导的LOW内吞作用 密度脂蛋白，使用胶体金标记的样品，在一些 对比度较低的样品上的实例。这些调查人员与 谢诺夫博士正在研究纤维蛋白原在血小板中的作用 聚合，将大大受益于增强的图像对比度 在STEM中可用。布洛克博士使用胶体金标记的标记物 下丘脑血管紧张素II的亚细胞定位研究 系统和雅各布森博士研究钴胺结合蛋白的作用 在肠-肝循环中，使用胶体金标记的抗体 卡巴拉明结合蛋白。这两名调查员将主要负责 显微镜在传统的传输模式下，但也可能受益于 STEM和LINK提供的颗粒计数软件。这个 霍夫博士和科尔博士以及原崎博士的项目也将需要 在二次和反向散射图像中提供的更高分辨率 这是在扫描电子显微镜(STEM)中可以获得的(与扫描电子显微镜相比)。在此模式下， 操作，他们将利用图像混合功能 显微镜。总而言之，一种多功能的、最先进的分析扫描 透射电子显微镜将极大地造福于大量 研究所的用户，并将履行急需的角色，如 学院范围内的设施。