National Resources for Imaging Mass Spectrometry

这个“资源”的核心是一种新型的二次离子质谱仪，多同位素成像质谱仪（MIMS）。二次离子质谱法是基于从样品表面溅射几个原子层。在喷射过程中，一些原子和团簇自发电离。这些“二次离子”是被分析表面组成的一个特征。在二次离子质谱仪中，二次离子根据其质量被分离，并形成所选质量分布的定量图像。MIMS提供高质量分离（M/deltaM > 10,000），高空间分辨率（< 50 nm），并具有同时记录多个原子质量图像的独特能力。最重要的是，MINIS首次（在细胞内水平）可以同时成像和测量任何同位素标记的分子的分布和积累，特别是稳定同位素，例如15N。因此，MIMS允许人们研究细胞微域中蛋白质、脂肪、糖和外来分子的定位、积累和周转。该资源与研究人员合作，利用MIMS的独特优势，带来细胞生物学、生理学、生理病理学、生物化学、免疫学、移植、毒理学、干细胞和基因转移研究方面的原始信息。MINIS为研究细胞内和细胞外代谢途径、信号转导、RNA和DNA表达和分布、脂肪酸运输、供体-受体细胞运输、干细胞筑巢和药物定位提供了强大的定量新方法。最后，稳定同位素的使用提供了一个标记可能性的世界，这是自动放射照相不可能做到的。它将恢复并扩大对人类示踪剂的使用。仪器开发（更亮的铯一次离子源，碘负一次离子源，双极Cs+/Isource，用铯覆盖样品表面的预分析）将把分辨率提高到20nm，将允许钙，碱金属（Na， K），金属（金属酶）的敏感测量，并将允许分析细胞表面的第一个原子层。二次离子形成的研究、自动化和强大的数据简化软件的开发、标准的开发以及细胞长期标记方法的开发将增加资源的广度，并将使用户社区受益。每年都会组织一次讲习班。资源网站向萌芽中的用户社区展示了丰富的信息。安全服务器允许在资源和用户之间交换大量数据。正在为用户社区建立一个web服务器，并将由资源维护。

The core of this 'Resource' is a novel type of secondary ion mass spectrometer, the Multi-Isotope Imaging Mass Spectrometer (MIMS). Secondary ion mass spectrometry is based upon the sputtering of a few atomic layers from the surface of a sample. During the ejection process, some atoms and clusters are spontaneously ionized. These 'secondary ions' are a characteristic of the composition of the analyzed surface. In a secondary ion mass spectrometer, the secondary ions are separated according to their mass, and a quantitative image of the distribution of the selected mass is formed. MIMS provides high mass separation (M/deltaM > 10,000), high spatial resolution (< 50 nm) and has the unique capability of simultaneously recording several atomic mass images. Of the utmost importance, MINIS makes it possible for the first time (and at the intracellular level) to simultaneously image the distribution and measure the accumulation of molecules labeled with any isotopes, in particular with stable isotopes, for example with 15N. Thus, MIMS allows one to study the localization, the accumulation and the turnover of proteins, fats, sugars and foreign molecules in cellular microdomains. The Resource collaborates with researchers to use the unique advantages of MIMS to bring original information in cell biology, physiology, physiopathology, biochemistry, immunology, transplantation, toxicology, stem cell and gene transfer research. MINIS offers a powerful and quantitative new method for studying intra and transcellular metabolic pathways, signal transduction, RNA and DNA expression and distribution, fatty acid transport, donor-receiver cellular trafficking, stem cell nesting and localization of drugs. Finally, the use of stable isotopes offers a world of labeling possibilities that were impossible with auto-radiography. It will revive and expand the use of tracers in humans. Instrumental development (brighter cesium primary ion source, iodine negative primary ion source, bipolar Cs+/Isource, preanalysis covering of the sample surface with cesium) will increase the resolution to 20nm, will allow sensitive measurements of calcium, alkali metals (Na, K), metals (metalloenzymes) and will allow analysis of the very first atomic layers at the cell surface. Study of secondary ion formation, development of automation and powerful data reduction software, development of standards, and development of methods for long term labeling of cells will increase the breadth of the Resource and will benefit the community of users. A workshop has been and will be organized every year. A Resource website displays a wealth of information to the budding community of users. A secure server allows exchanges of large reams of data between the Resource and users. A webserver for the community of users is being built and will be maintained by the Resource.