在LC-ESI-HRMS的分析过程中揭示Per-和Polyfluoroalkyl物质的来源碎片化模式
Ke Wang1,2, Runyun Wang1,2, Wenyu Shan1,2
1College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
Environmental science & technology
|December 13, 2024
概括
在喷电离子质谱中的源内碎片化 (ISF) 影响了对和多醇基物质 (PFAS) 的分析. 碳氧酸盐头组驱动ISF路径,影响准确的PFAS识别和量化.
科学领域:
- 环境化学环境化学
- 分析化学 分析化学
- 质谱测量质量谱测量
背景情况:
- 在电喷气电离 (ESI) 过程中,对和多基物质 (PFAS) 的源内碎片化 (ISF) 复杂化了液态染色体质谱法 (LC-MS) 分析.
- ISF导致分子离子反应减少和质谱 (MS) 特征的错误注释,阻碍了准确的PFAS检测和识别.
- 了解ISF机制对于改进PFAS的分析方法至关重要.
研究的目的:
- 系统地识别易患ISF的PFAS结构.
- 阐明PFAS的ISF所涉及的碎片化途径.
- 为准确识别PFAS及其降解产品提供洞察力.
主要方法:
- 使用LC-MS对12个类的82个PFAS进行分析.
- 系统地识别展示ISF的结构.
- 调查碎片化路径,包括债券裂变和消除.
主要成果:
- 观察到38种含有碳酸盐头组的PFAS的ISF高达100%.
- 确定了七种ISF通路,通常由CO2损失启动,涉及C-CO2-,C-O和C-C键裂解以及HF/CO2HF消除.
- 增加的MS温度显著加剧了大多数PFAS的ISF.
结论:
- 碳酸基组是PFAS中ISF的一个关键决定因素.
- 了解ISF路径,特别是二氧化碳损失,对于准确的PFAS分析至关重要.
- 应优化分析条件,如MS温度,以最大限度地减少ISF,以改善PFAS识别.
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