Speir J P, Gorman G S, Pitsenberger C C, Turner C A, Wang P P, Amster I J
Department of Chemistry, University of Georgia, Athens 30602.
Anal Chem. 1993 Jul 1;65(13):1746-52. doi: 10.1021/ac00061a018.
Ions formed by a single laser desorption event can be remeasured more than 500 times in a Fourier transform ion cyclotron resonance spectrometer. Quadrupolar excitation and collisional axialization are used to move ions located in any region of the ICR cell to the center of the cell, where they can be effectively detected. With this method, the signal from ions formed by a single laser desorption event is averaged for 200 remeasurement cycles with an efficiency in excess of 99.5% per cycle. Collisions of ions with helium are found to give higher remeasurement efficiencies than collisions with methane, due to reduced scattering losses by the lighter collision gas. With this method, ions that are stored in the analyzer cell for more than 1 hour can be detected. This technique is shown to be compatible with high-resolution data acquisition. Ions formed by one laser desorption event are remeasured at eight bandwidths, demonstrating low-resolution, wide-mass-range analysis and high-resolution, narrow-mass-range analysis of the same group of ions.
在傅里叶变换离子回旋共振光谱仪中，单次激光解吸事件形成的离子可被重新测量500多次。利用四极激发和碰撞轴向化，可将位于离子回旋共振（ICR）池任何区域的离子移动到池中心，在那里它们能被有效检测。采用这种方法，单次激光解吸事件形成的离子信号在200次重新测量循环中进行平均，每次循环的效率超过99.5%。发现离子与氦的碰撞比与甲烷的碰撞具有更高的重新测量效率，这是因为较轻的碰撞气体导致散射损失减少。通过这种方法，可以检测在分析池中存储超过1小时的离子。该技术被证明与高分辨率数据采集兼容。单次激光解吸事件形成的离子在八个带宽下进行重新测量，展示了对同一组离子的低分辨率、宽质量范围分析和高分辨率、窄质量范围分析。
