Evaluation of Binding Interactions of Ions Generated by Electrospray Ionization

该项目属于分析和表面化学领域以及质谱分析领域。 在为期三年的持续资助期间，德克萨斯大学奥斯汀分校的Brodbelt教授和她的学生将对通过碰撞诱导解离（CID）和化学电离（CI）阳离子化形成的离子复合物进行系统的比较研究，并直接通过电喷雾电离（ESI）形成类似物。 这些研究旨在确定影响离子形成的化学过程，并提供对分子相互作用的深入了解，这些分子相互作用导致在ESI和更软的电离过程（如CID和CI）之间观察到的离子碎裂模式存在显著差异。 此外，相对阳离子-底物结合强度将与底物结构特征相关，包括特定官能团和空间特征的存在。 除了为离子形成过程提供新的基本见解外，这项研究还有望改善基于ESI的质谱分析的分析实用性。 电喷雾离子化是分析质谱中发展最快的离子化技术。 这是一种可靠的电离技术，所需设备简单且相对便宜。 然而，用ESI（一种“苛刻”电离方法）获得的离子碎裂模式与用“较软”电离方法（如CID和CI）观察到的离子碎裂模式显著不同。 这项研究的目的是了解伴随着离子形成事件的化学过程，从而扩大范围和灵敏度的ESI为基础的质谱作为一种分析工具。

This project is in the area of analytical and surface chemistry and in the subfield of mass spectrometry. During the tenure of this three-year continuing grant, Professor Brodbelt and her students at the University of Texas at Austin will carry out a systematic comparative examination of ion complexes formed by collisionally induced dissociation (CID) and cationization by chemical ionization (CI) with their analogues formed directly by electrospray ionization (ESI). These studies are designed to identify the chemical processes that impact ion formation and to provide insights into the molecular interactions that give rise to the significant differences in ion fragmentation patterns observed between ESI and softer ionization processes such as CID and CI. Additionally, the relative cation-substrate binding strengths will be correlated with substrate structural characteristics, including the presence of specific functional groups and steric features. In addition to providing new fundamental insights into ion formation processes, this research is expected to lead to improvements in the analytical utility of ESI-based mass spectrometry. Electrospray ionization is the most rapidly growing ionization technique in analytical mass spectrometry. It is a robust ionization technique and the requisite equipment is simple and relatively inexpensive. However, ion fragmentation patterns obtained with ESI, a "harsh" ionization method, differ significantly from those observed with "softer" ionization methods such as CID and CI. This research is aimed at understanding the chemical processes attendant to the ion formation event and thereby extend the scope and sensitivity of ESI-based mass spectrometry as an analytical tool.