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AC Electrokinetic Phenomena Generated by Microelectrode Structures
Published on: July 28, 2008
在电喷离子化中充电和超充电分子的机制
Anthony T Iavarone1, Evan R Williams
1Contribution from the Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|February 20, 2003
概括
电子喷雾液滴的表面张力显著影响分析物电荷. 这项研究支持电喷离子化中多重电荷离子形成的带电残留机制.
科学领域:
- 分析化学 分析化学
- 物理化学 物理化学
- 质谱测量质量谱测量
背景情况:
- 电喷电离 (ESI) 中多重电荷离子的形成机制是一个长期的辩论.
- 影响ESI中分析离子电荷状态的因素是复杂的,并未完全理解.
研究的目的:
- 研究溶剂表面张力的作用,以确定ESI中各种分析物的充电程度.
- 提供支持或反驳ESI中现有的离子形成机制的证据.
主要方法:
- 从不同组成的溶液中,电压喷射电离聚烯胺树脂体,细胞染色体c,聚乙烯糖醇和1,n-氨基.
- 通过使用单元溶液和混合物,包括m-nitrobenzyl alcohol (m-NBA),系统地改变溶剂表面张力.
- 分析剂电荷状态和溶剂表面张力之间的相关性分析,并与雷利限制电荷进行比较.
主要成果:
- 分析物电荷状态与溶解过程中晚期的电喷液滴的表面张力有显著的相关性.
- 根据初始溶液与m-NBA相对的表面张力添加了m-NBA改变的分析物充电.
- 观察到树状体和1,n-氨基的电荷状态与它们计算的雷利限制电荷之间存在强烈的相关性.
结论:
- 结果强烈支持充电残留机制作为ESI中多重电荷有机离子形成的主要途径.
- 离子蒸发机制似乎扮演的角色不那么重要,特别是在树状体和1,n-diaminoalkanes.
- 溶剂表面张力是一个关键的,可量化的因素,影响电喷离子化中的离子充电.
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