Electrohydrodynamics of Gas-Assisted Electrospray Ionization Mass Spectrometry.
Electrohydrodynamics of Gas-Assisted Electrospray Ionization Mass Spectrometry.
复制标题
气体辅助电喷雾电离质谱的电流体动力学。
DOI：
10.1021/jasms.0c00197
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发表时间：
2020
影响因子：
3.2
通讯作者：
Fedorov,AndreiG
中科院分区：
文献类型：
--
作者：
Lee,JungY;Kottke,PeterA;Fedorov,AndreiG
气流辅助通常用于ESI- ms中，以改善输运和脱溶，对潜在现象的基本理解对于改善ESI源和ms耦合的气动界面至关重要。为此，考虑带电气溶胶羽流内部的空间电荷相互作用，建立了一个电流体动力学模型，用于模拟气流和电场联合作用下的带电液滴动力学。该模型在COMSOL中实现，利用一种形式化的方法，将液滴轨迹建立为以电喷雾电流定义的频率喷射的连续液滴序列。该模型用于评估两种不同流动配置的效果，并与无辅助气体的电喷雾的基线护理进行比较。模拟的气流是与ESI喷雾同轴的射流，有或没有施加涡量（旋流）。由大初级液滴和小子代液滴组成的双峰液滴群的液滴轨迹模拟表明，由于惯性分离，涡旋辅助射流有选择地将较小的液滴传输到MS中，具有独特的能力。不同气体流动条件下氟化磷hazines的ESI-MS分析支持模型预测。在这项工作中开发的电流体动力学模型提供了一个通用的工具来分析和设计气动ESI界面，严格结合阻力，惯性和空间电荷排斥，可以用作优化带电液滴传输的强大模拟方法，并最终提高气辅助ESI- ms工作流程的分析性能。
Gas-flow assistance is commonly used in ESI-MS for improved transport and desolvation, and fundamental understanding of the underlying phenomena is essential for improvement of aerodynamic interfaces that couple ESI sources and MS. For this purpose, an electrohydrodynamic model is developed for simulation of charged droplet dynamics under the combined effects of gas flow and electric fields with consideration of space charge interactions within the charged aerosol plume. The model is implemented in COMSOL by exploiting a formalism for establishing the droplet trajectories as a sequence of successive droplets ejected at a frequency defined by the electrospray current. The model is used to assess the effect of two distinct flow configurations and compared to the baseline care of electrospray without assist gas. The simulated flows are jet flows oriented coaxially with the ESI spray, with and without imposed vorticity (swirling). Droplet trajectory simulations of a bimodal droplet population consisting of large primary droplets and small progeny droplets reveal a unique capability for vortical assist jet flow to selectively transmit smaller droplets into the MS due to inertial separation. ESI-MS analysis of fluorinated phosphazines subjected to the different gas flow conditions supports the model predictions. The electrohydrodynamic model developed in this work provides a versatile tool to analyze and design aerodynamic ESI interfaces with rigorous incorporation of drag, inertia, and space-charge repulsion and can be used as a powerful simulation methodology for optimizing charged droplet transmission and ultimately improved analytical performance of gas-assisted ESI-MS workflows.