使用GC-APCI-HRMS发现线性和碳化合物的燃烧式源氧化
Lindsay P Brown1, Wesley B Seaton1, Joshua B Powers1
1Department of Chemistry, University of Tennessee, Knoxville, Tennessee, USA.
Journal of mass spectrometry : JMS
|September 26, 2024
概括
大气压化学电离 (APCI) 可以导致线性和碳化合物 (LSHs) 的源氧化. 这项研究揭示了氧化离子形成的类似燃烧的机制,这对于分析石化物质至关重要.
科学领域:
- 分析化学 分析化学
- 质谱测量质量谱测量
- 有机化学 有机化学
背景情况:
- 大气压化学电离 (APCI) 是线性和碳化合物 (LSH) 分析的常见方法,通常产生[M-H]+离子.
- 在APCI和其他大气压源中的源氧化复杂化了LSH分析,因为它产生了各种离子产物.
- 了解LSH氧化机制对于描述复杂的碳化合物混合物至关重要,特别是在石化行业.
研究的目的:
- 通过使用气体染色学与高分辨率质谱学 (GC-HRMS) 结合自定义APCI接口来研究LSHs的源氧化.
- 阐明氧化LSH离子的形成机制及其与大气中的水和反应物种的关系.
- 提出GC-APCI-HRMS中观察到的LSH氧化产品的机制,并与燃烧过程进行并行.
主要方法:
- 使用气体染色学与高分辨率质谱学 (GC-HRMS) 相结合.
- 采用一个定制的大气压化学电离 (APCI) 接口.
- 用稳定同位素标记水和LSH标准进行实验,以追踪氧化途径和碎片化模式.
主要成果:
- 观察到氧化离子丰富度和大气中的水之间的正相关性,尽管实验排除了基于水的氧气.
- 确定了多个氧化LSH离子,其氧化位点位于初级和二级碳上,通过标记标准的碎片化分析揭示出来.
- 证明了APCI接口促进了等离子体辅助的,类似于燃烧的过程,导致激素介导的LSH氧化.
结论:
- 建议在GC-APCI-HRMS中形成LSH氧化产物的一种类似燃烧机制.
- 已识别的氧化离子在石化产品中始终产生,使其能够进行表征.
- 这些发现对于精确分析工业应用中的复杂碳化合物混合物至关重要.
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