Development of Single Particle Analyzer of Mass and Mobility (SPAMM)

单粒子质量和迁移率分析仪（SPAMM）的开发

• 批准号: 8290324
• 负责人: Evan R Williams
• 金额: $ 22.92万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8290324
• 关键词: Buffers; Cell Mobility; Cell physiology; Charge; Chemistry; Complex; Coupled; Data; Detection; Development; Devices; Dissociation; Electrospray Ionization; Electrostatics; Elements; Fourier Transform; Gases; Helium; Heterogeneity; Individual; Ions; Lifting; Macromolecular Complexes; Mass Spectrum Analysis; Measurement; Measures; Methods; Modification; Molecular; Molecular Weight; Nitrogen; Particle Size; Phase; Photons; Play; Relative (related person); Reporting; Resolution; Role; Sampling; Services; Shapes; Solutions; Structure; System; Techniques; Therapeutic Agents; Time; Travel; Vacuum; austin; base; dalton; density; design; electric field; experience; improved; instrument; instrumentation; ion mobility; ionization; mass analyzer; mass spectrometer; molecular assembly/self assembly; molecular size; nanoscale; particle; pressure; programs; research study; stoichiometry; tandem mass spectrometry; theories

DESCRIPTION (provided by applicant): Mass spectrometry is rapidly becoming a powerful method for the structural elucidation of macromolecular complexes, and can provide complimentary information to conventional biophysical methods. Intact complexes can be lifted out of solution with electrospray ionization, which adds many charges to these molecular assemblies. Experiments have shown that in numerous cases, these gas-phase ions retain many elements of their solution-phase structure. A direct mass measurement provides a rapid measure of the stoichiometry of complexes, even for heterogeneous mixtures. Fragmentation of complexes can yield information about the connectivity of subunits within the complex. Additionally, ion mobility-based approaches are beginning to provide cross-sectional measurements of complexes, making it possible to obtain complementary shape information. A challenge in applying mass spectrometry to even larger complexes is sample heterogeneity, which can result in unresolved charge-state distributions. An additional challenge is that the sensitivity of many mass spectrometers decreases with increasing mass-to-charge ratio (m/z), which makes it more difficult to detect complexes with molecular weights of several mega Daltons and higher with high sensitivity. One aspect of electrospray ionization is that the degree of charging generally increases with molecular size. This makes charge detection mass spectrometry an attractive means of analyzing large macromolecular complexes, because it has the advantage that individual ions possessing multiple charges can be readily detected. Because charge will increase with size, the sensitivity of this technique actually improves with increasing molecular weight. The heterogeneity of the sample does not interfere with mass or mobility measurements, because each ion is analyzed individually. We plan to develop a Single Particle Analyzer of Mass and Mobility (SPAMM), which will incorporate m/z and charge detection measurements so that the masses of individual ions can be rapidly measured. Tandem mass spectrometry capabilities will be incorporated into this dual electrostatic ion trap instrument which will make it possible to measure a fragmentation spectrum of an individual ion of known mass (initial studies will focus on infrared multiple photon dissociation, although other methods could also be incorporated). Finally, ion mobility capabilities will be integrated into this device to make it possible to measure the mass of an ion, and subsequently obtain its absolute collision cross section, which provides information about the shape of the complex. Cross sections can also be obtained for fragments generated by the dissociation of a complex, providing information about the contribution of subunit connectivity to the overall structure of the complex. Because the induced current in this device is directly proportional to the number of charges on the macromolecular complex, sensitivity should increase with increasing particle size making this method applicable too much larger heterogeneous complexes than can be currently analyzed with commercially available mass spectrometers.

描述（由申请人提供）：质谱法正在迅速成为大分子复合物结构阐明的强大方法，并可以为常规生物物理方法提供免费信息。完整的复合物可以通过电喷雾电离从溶液中提取，从而为这些分子组件增加了许多电荷。实验表明，在许多情况下，这些气相离子保留了其溶液相结构的许多元素。直接的质量测量可以快速衡量复合物的化学计量法，即使对于异质混合物也是如此。复合物的碎片可以产生有关复合物中亚基的连通性的信息。此外，基于离子的移动性方法开始提供对复合物的横截面测量结果，从而使获得互补的形状信息成为可能。样品异质性是将质谱施加到更大复合物上的挑战，这可能导致未解决的电荷状态分布。另一个挑战是，许多质谱仪的敏感性随着质谱量的增加（M/z）降低，这使得检测几个巨型达尔顿的分子量的复合物变得更加困难，并且具有高灵敏度。电喷雾电离的一个方面是，充电程度通常随分子大小而增加。这使电荷检测质谱法成为分析大型大分子复合物的有吸引力方法，因为它具有很容易检测到具有多个电荷的个体离子的优势。因为电荷会随大小的增加而增加，所以该技术的灵敏度实际上会随着分子量的增加而提高。样品的异质性不会干扰质量或迁移率测量值，因为每个离子都会单独分析。我们计划开发质量和迁移率（SPAMM）的单个粒子分析仪，该分析仪将结合M/Z并进行电荷检测测量值，以便可以快速测量单个离子的质量。串联质谱能力将纳入该双静电离子陷阱仪器中，这将使可以测量已知质量的个体离子的碎片化光谱（初步研究将集中在红外多个光子分离上，尽管其他方法也可以纳入其他方法） 。最后，离子迁移率能力将集成到该设备中，以使离子的质量成为可能，并随后获得其绝对碰撞横截面，该截面提供了有关复合物形状的信息。也可以通过复合物解离产生的片段获得横截面，从而提供了有关亚基连接对复合物的整体结构的贡献的信息。由于该设备中的诱导电流与大分子复合物上的电荷数直接成正比，因此敏感性应随着粒径的增加而增加，这使得该方法适用于目前可以分析过过多的异质复合物，而不是通过市售的质谱仪进行分析。