在不同电离模式下对类固醇和其他类固醇进行质谱分析:灵敏度和氧化人工物
Kevin D McCarty1, F Peter Guengerich1
1Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States.
Journal of the American Society for Mass Spectrometry
|June 27, 2025
概括
在对类固醇的质谱 (MS) 分析中,特别是在大气压化学电离 (APCI) 中,突出的2 amu损失往往通过遮蔽前体离子来复杂化结构赋值.
科学领域:
- 分析化学 分析化学
- 质谱测量质量谱测量
- 类固醇化学 类固醇化学
背景情况:
- 使用质谱法 (MS) 进行类固醇分析可能因意外的离子损失而复杂化.
- 在使用大气压化学电离 (APCI) 的氧类固醇分析中观察到显著的2和4 amu损失.
- 这些损失可能会导致结构性分配的混.
研究的目的:
- 通过MS通过氧类固醇分析调查2amu损失的性质和患病率.
- 为了比较APCI和加热电喷电离 (HESI) 之间的这些损失的发生,MS.
- 评估这些损失对类固醇检测灵敏度和结构阐释的影响.
主要方法:
- 使用APCI MS和HESI MS对44种类固醇和类固醇的分析.
- 研究了各种电离条件和移动相添加剂 (NH4F).
- 2n amu损失和前体离子强度的量化.
主要成果:
- 在44种类固醇中,36种类固醇在APCIMS中显示了2n amu损失,通常作为基峰.
- 在较少的病例中,HESI MS表现出较弱的2n amu损失.
- 根据离子化方法,类固醇敏感性有所不同,APCI偏好 Δ5 类固醇/类固醇,HESI偏好 Δ4 类固醇.
- 化 (NH4F) 添加剂在ESI+中提高了灵敏度.
结论:
- 在氧类固醇分析中观察到的突出的2n amu损失通常是APCI MS.的工件.
- 这些人工损失可以显著阻碍前体离子的检测,并使结构确定复杂化.
- 了解这些碎片化模式对于准确的类固醇分析至关重要.
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