Williams D Keith, McAlister Graeme C, Good David M, Coon Joshua J, Muddiman David C
W.M. Keck FT-ICR Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
Anal Chem. 2007 Oct 15;79(20):7916-9. doi: 10.1021/ac071444h. Epub 2007 Sep 15.
A dual electrospray ionization source (ESI) has been modified to simultaneously produce cations and anions, one from each emitter, for performing rapid electron-transfer dissociation (ETD) ion/ion reactions on a hybrid linear ion trap-orbitrap mass spectrometer. Unlike the pulsed dual ESI sources that were used to generate ETD reagent ions, this source separates the emitters in space, rather than time, by physically switching which one is in front of the atmospheric inlet. The new arrangement allows for substantially enhanced spray stability and decreased switching times (<or=30 ms), allowing for more tandem-MS spectra per unit time. Herein, we demonstrate the stability of the ETD anion population and the ability to identify several c- and z-type product ions from multiply protonated peptide cations.
一种双电喷雾电离源(ESI)已被改进,可同时产生阳离子和阴离子,每个发射器各产生一种,以便在混合线性离子阱-轨道阱质谱仪上进行快速电子转移解离(ETD)离子/离子反应。与用于产生ETD试剂离子的脉冲双ESI源不同,该源通过物理切换位于大气入口前方的发射器,在空间而非时间上分离发射器。这种新的布局可显著提高喷雾稳定性并缩短切换时间(≤30毫秒),从而在单位时间内获得更多串联质谱图。在此,我们展示了ETD阴离子群体的稳定性以及从多个质子化肽阳离子中识别几种c型和z型产物离子的能力。