Stable compensation voltages in differential mobility spectra by separating neutral vapors from ions in sample flow
Stable compensation voltages in differential mobility spectra by separating neutral vapors from ions in sample flow
复制标题
通过将中性蒸气与样品流中的离子分离来稳定微分迁移谱中的补偿电压
DOI：
10.1007/s12127-020-00257-0
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发表时间：
2020
影响因子：
--
通讯作者：
Eiceman, G. A.
中科院分区：
文献类型：
--
作者：
Fowler, P. E.;Tarassov, A.;Lee, G-I.;Pasupuleti, D.;Ray, A.;Eiceman, G. A.
在具有环境压力离子源的小型平面差分迁移谱仪中，样品的离子和中性蒸气通常从离子源直接流入并穿过分析仪区域。虽然制造和操作简单方便，但在该设计中源自样品的产物离子可能与中性未反应样品或基质成分形成簇，特别是在 50 ppm 或更高的蒸气水平下。此类中性物质的不受控制和变化的水平会导致离子簇的浓度依赖性形成，并且 DMS 谱图的补偿电压发生变化。通过将离子提取到纯化气体的逆流中，排除中性蒸气（从 ppm 到百分比水平），获得了产物离子的稳定补偿电压。电场和净化空气的接口放置在离子源和分析仪区域之间，并通过同轴和正交离子提取进行操作。利用质子化单体和磷酸二甲酯质子结合二聚体的峰位置变化来确定中性物去除的有效性，显着避免了高蒸汽浓度的二氯甲烷、异丙醇、水和甲醇的电离化学的复杂性。使用 COMSOL 和 SIMION 进行的计算机模拟阐明了两种操作模式下离子和气体的流动。研究结果预示着多级 DMS 分析仪的发展，其中蒸汽可能会在一个阶段中有意添加作为改性剂，并在进入后续阶段之前被去除。
In small planar differential mobility spectrometers with ambient pressure ion sources, both ions and neutral vapors of sample commonly flow from the ion source directly into and through the analyzer region. Although simple and convenient both for fabrication and operation, product ions derived from sample in this design may form clusters with neutral unreacted sample or matrix constituents particularly at vapor levels of 50 ppm or greater. Uncontrolled and changing levels of such neutrals cause concentration dependent formation of ion clusters with variations in compensation voltages of DMS spectra. Stable compensation voltages were achieved for product ions by extracting ions into a counter flow of purified gas excluding neutral vapors from ppm to percent levels. An interface with electric fields and purified air was placed between ion source and analyzer region and operated with both on-axis and orthogonal extraction of ions. Effectiveness of removal of neutrals was determined using variations in peak position for protonated monomers and proton bound dimers of dimethylmethylphosphate, significantly avoiding complications of ionization chemistry with high vapor concentrations of methylene chloride, iso-propanol, water, and methanol.In-silicomodeling using COMSOL and SIMION clarified the flow of ions and gases in two modes of operation. Findings anticipate the development of multiple stages of DMS analyzers where vapors may be intentionally added as modifiers in one stage and removed before entering a subsequent stage.
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影响因子：
1.3
作者：
COHEN, MJ;KARASEK, FW
通讯作者：
KARASEK, FW
在环境压力和温度下，在空气中进行离子解离的串联差分迁移谱测定。
DOI：
--
发表时间：
2015
期刊：
In Analysis
影响因子：
--
作者：
M. Menlyadiev;A. Tarassov;A. M. Kielnecker;G. Eiceman
通讯作者：
G. Eiceman
纯化空气中的串联差分迁移光谱法，用于高速选择性蒸气检测。
影响因子：
7.4
作者：
M. Menlyadiev;G. Eiceman
通讯作者：
G. Eiceman
DOI：
10.1016/s1464-3456(00)x8001-5
发表时间：
2000
期刊：
--
影响因子：
--
作者：
S. Görög
通讯作者：
S. Görög
影响因子：
7.4
作者：
Schneider, Bradley B.;Covey, Thomas R.;Coy, Stephen L.;Krylov, Evgeny V.;Nazarov, Erkinjon G.
通讯作者：
Nazarov, Erkinjon G.