在碰撞引起的解离过程中,去化酸是否会失去一氧化碳?
Yingying Liu1,2, Xue Wang1,2, Danyang Zhang1
1Tea Research Institute, Chinese Academy of Agricultural Sciences, Laboratory of Quality and Safety Risk Assessment for Tea Products (Hangzhou), Ministry of Agriculture and Rural Affairs, Hangzhou, China.
Journal of mass spectrometry : JMS
|December 26, 2023
概括
无质子酸的碰撞诱导解离 (CID) 意外产生了一种主要的m/z 93离子. 这是因为初始的m/z 77片段与氧气反应,形成氧化添加物,必须在MS/MS光谱分析中考虑.
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:
- 脱碳氧化是碰撞诱导解离 (CID) 中脱化碳酸的主要碎片化途径.
- 在CID质谱学中,去质子化酸的碎片化通常会产生一个m/z77离子.
研究的目的:
- 为了调查脱质酸CID质谱中意想不到的主导的m/z 93峰值.
- 为了阐明酸离子的碎片化机制,并确定氧化添加物的起源.
主要方法:
- 碰撞诱导解离 (CID) 质谱仪在Q轨道仪器上.
- 理论计算以建模碎片化路径.
- 18 O-同位素标记研究.
- MS3实验以确认离子结构.
主要成果:
- 脱质酸CID质谱中占主导的峰值为m/z 93,而不是预期的m/z 77.
- 在质量分析仪内,m/z 77化离子与微量分子氧 (O2) 反应.
- 这种反应形成m/z 93酸盐离子和其他含氧离子.
结论:
- 酸离子的碎片化始于脱碳化.
- 通过与微量O2反应形成的氧添加物至关重要,并且必须在MS/MS中考虑子酸的光谱注释.
- 这一发现影响了对相关化合物的质谱数据的解释.
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