Moradian Annie, Douglas D J
Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1, Canada.
Rapid Commun Mass Spectrom. 2007;21(20):3306-10. doi: 10.1002/rcm.3224.
We describe experimental investigations of mass analysis using an island of stability with a linear quadrupole with a 2.0% added octopole field. The island is formed by auxiliary quadrupole excitation. The experiments confirm the results of previous computer simulations (Konenkov et al., J. Am. Soc. Mass Spectrom. 2007; 18: 826-834). With the resolving direct current (dc) applied to the quadrupole so that the Mathieu parameter a > 0, conventional mass analysis with applied radio-frequency (rf) and dc and no auxiliary excitation is possible. In this case, use of an island of stability yields similar peak shape and resolution. However, with the polarity of the resolving dc reversed, so that a < 0, only very low resolution can be obtained; the added octopole prevents conventional mass analysis. By using a stability island when a < 0, the resolution is substantially improved. In this case the use of an island allows mass analysis under conditions where the added octopole field severely degrades conventional analysis. The experiments also confirm the position of the island predicted by the simulations.
我们描述了利用带有2.0%附加八极场的线性四极杆的稳定岛进行质量分析的实验研究。该稳定岛由辅助四极杆激发形成。实验证实了先前计算机模拟的结果（科年科夫等人，《美国质谱学会杂志》，2007年；18: 826 - 834）。当向四极杆施加分辨直流电压以使马修参数a > 0时，施加射频（rf）和直流电压且无辅助激发的传统质量分析是可行的。在这种情况下，使用稳定岛会产生相似的峰形和分辨率。然而，当分辨直流电压的极性反转，使得a < 0时，只能获得非常低的分辨率；附加的八极场会阻碍传统质量分析。当a < 0时通过使用稳定岛，分辨率会显著提高。在这种情况下，使用稳定岛能够在附加八极场严重降低传统分析性能的条件下进行质量分析。实验还证实了模拟预测的稳定岛的位置。
