Extending the mass range of the quadrupole ion trap using axial modulation
Extending the mass range of the quadrupole ion trap using axial modulation
复制标题
使用轴向调制扩展四极离子阱的质量范围
DOI：
10.1002/rcm.1290030706
复制
发表时间：
1989
影响因子：
2
通讯作者：
D. Hunt
中科院分区：
文献类型：
--
作者：
R. Kaiser;J. N. Louris;J. Amy;R. Cooks;D. Hunt
利用Cs+离子轰击固体和液体基质，在四极离子陷阱上实现了二次离子质谱仪。四烷基铵阳离子和质子化多肽是在外部源中使用脉冲初级离子束产生的，它们被注入离子陷阱，在那里它们在与氦浴气体碰撞的过程中减速并被捕获。然后，通过使用质量选择性不稳定性扫描记录质谱图来检查陷阱的内容物。为了提高对这些俘获离子的检测性能，在质量分析步骤中使用了轴向调制技术来引起离子从陷阱中的共振抛射。施加到端盖上的附加交流电压会在低于正常稳定极限的QZ值处引起离子的共振喷射。这将使商用离子陷阱的质量极限从650 Da提高到约1300 Da而不损失分辨率和灵敏度，并在灵敏度降低的情况下提高到20000 Da以上。
Secondary-ion mass spectrometry, using Cs+ ion bombardment of solid and liquid matrices, has been implemented on a quadrupole ion trap. Tetraalkylammonium cations and protonated peptides, generated in an external source using a pulsed primary-ion beam, are injected into the ion trap where they are decelerated and trapped in the course of collisions with the helium bath gas. The contents of the trap are then examined by recording a mass spectrum using the mass-selective instability scan. To improve performance in the examination of these trapped ions, the technique of axial modulation is used to cause resonance ejection of ions from the trap during the mass-analysis step. The supplementary AC voltage applied to the end-caps causes resonant ejection of ions at qz values below those which correspond to the normal stability limit. This is demonstrated to increase the mass limit of a commercial ion trap from 650 Da to approximately 1300 Da with no loss in resolution or sensitivity, and to more than 20 000 Da at reduced sensitivity.