异构体化多双基的气相反应性
Emma H Palm1,2, Josefin Engelhardt3, Sofja Tshepelevitsh4
1Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16, 114 18 Stockholm, Sweden.
Journal of the American Society for Mass Spectrometry
|April 19, 2024
概括
二维离子移动性光谱 (2D-IMS) 成功区分了化多二 (OH-PCB) 异构体. 这种方法揭示了异构体碎片及其独特的碎片化途径,增强了OH-PCB的识别.
科学领域:
- 分析化学 分析化学
- 环境科学 环境科学
- 质谱测量质量谱测量
背景情况:
- 使用传统的高分辨率质谱法 (HRMS) 区分氧化多二 (OH-PCB) 的立体和定位异构体是具有挑战性的.
- 几乎相同的碎片谱 (MS2),保留时间和碰撞截面 (CCS) 值阻碍了异构体的分化.
研究的目的:
- 使用二维离子移动性谱法 (2D-IMS) 来区分OH-PCB异构体.
- 通过与HRMS (IMS-HRMS) 结合的离子流动性光谱学来研究OH-PCB碎片结构和碎片化机制.
主要方法:
- 使用循环IMS-HRMS进行18个OH-PCB的流量注入.
- 测量了MS2光谱和CCS值,用于去质子化分子和碎片离子.
- 计算了基布斯自由能量和CCS值,以阐明碎片离子结构.
主要成果:
- 离子流动性成功地分离了碎片离子,表明异构体碎片的形成.
- 不同的原始OH-PCB异构体产生了不同数量的异构体片段峰值.
- 计算的吉布斯自由能量和CCS值有助于将结构分配给像[M-H-HCl]−这样的同位素碎片.
- 异构体碎片的进一步碎片化揭示了异构体特定的碎片化途径.
结论:
- 2D-IMS为区分OH-PCB异构体提供了一个强大的工具.
- 这项研究为OH-PCB碎片化机制和异构体识别提供了新的见解.
- 这种方法提高了对复杂环境污染物的准确识别能力.
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