HIGH ENERGY COLLISIONAL ACTIVATION

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。 在许多情况下，使用高能 CAD 就无需进行多级 MS/MS。对于现在使用的低能量激活方法，可能需要一个或多个额外的 MS/MS 阶段，因为低离子内部能量会导致对一种不提供信息的碎片途径进行采样。 对于我们的 12-T Bruker FTMS 仪器，经计算，多电荷蛋白质离子的实验室框架能量为 10 KeV 量级或更高。 高能 CAD 产生的内部能量的广泛分布导致对多个碎片路径的采样和信息丰富的产物离子谱。除了对目标分子进行定量等情况外，使用多级 MS/MS 提取信息在时间和样品方面都非常昂贵。 陷阱设计的最新进展已经融入了补偿的思想，以提高检测性能。所有这些努力都试图通过重塑捕获电场来消除捕获电场对检测性能的不利影响。这些有害影响之一是高能 CAD 导致的高半径分布离子的检测性能降低。补偿方面的进步提供了一种方法来消除阻碍在 FTMS 实验中使用高能 CAD 的这一限制。

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. In many cases, the need to do multiple stages of MS/MS is removed by the use of high-energy CAD. With low energy activation methods now in use, one or more additional stages of MS/MS may be required because the low ion internal energy results in the sampling of one fragmentation pathway that is non informative. The laboratory frame energies of multiply charged protein ions are calculated to be the order of 10 KeV or more for our 12-T Bruker FTMS instrument. The broad distribution of internal energies that are produced by high-energy CAD result in the sampling of multiple fragmentation pathways and an information rich product ion spectrum. Except in cases such as the quantitation of a targeted molecule, the use of multiple stages of MS/MS to extract information is costly in terms of time and sample. Recent advances in trap design have incorporated the ideas of compensation to improve the detection peformance. All of these efforts seek to remove the detrimental effects of the trapping electric field on detection performance by reshaping the trapping electric field. One of these detrimental effects is the reduction of detection performance for ions that are distributed at high radius that would result from high-energy CAD. Advances in compensation provide a means to remove this limitation that impedes the use of high-energy CAD in the FTMS experiment.