Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana, USA.
J Am Soc Mass Spectrom. 2010 Nov;21(11):1852-6. doi: 10.1016/j.jasms.2010.06.023. Epub 2010 Jul 8.
A novel high-frequency alternating current (AC) electrospray ionization (ESI) source has been developed for applications in mass spectrometry. The AC ESI source operates in a conical meniscus mode, analogous to the cone-jet mode of direct current (DC) electrosprays but with significant physical and mechanistic differences. In this stable conical-meniscus mode at frequencies greater than 50 kHz, the low mobility ions, which can either be cations or anions, are entrained within the liquid cone and ejected as droplets that eventually form molecular ions, thus making AC ESI a viable tool for both negative and positive mode mass spectrometry. The performance of the AC ESI source is qualitatively shown to be frequency-dependent and, for larger bio-molecules, the AC ESI source produced an ion signal intensity that is an order of magnitude higher than its DC counterpart.
一种新型高频交流（AC）电喷雾电离（ESI）源已被开发用于质谱应用。AC ESI 源在圆锥形弯月面模式下运行，类似于直流（DC）电喷雾的锥射流模式，但具有显着的物理和机械差异。在大于 50 kHz 的频率下，处于这种稳定的圆锥形弯月面模式下，低迁移率离子（可以是阳离子或阴离子）被夹带在液体圆锥体内，并以液滴形式喷出，最终形成分子离子，从而使 AC ESI 成为正、负离子模式质谱的可行工具。AC ESI 源的性能被定性地证明是频率依赖性的，对于较大的生物分子，AC ESI 源产生的离子信号强度比其 DC 对应物高一个数量级。
