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Updated: Jun 30, 2025

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Synthesis and Mass Spectrometry Analysis of Oligo-peptoids
Published on: February 21, 2018
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盐桥离子气态结构使有效的负离子电子捕获解离成为可能
Ning Wang1, Sugyan M Dixit1, Teresa Lee1
1Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States.
Journal of the American Society for Mass Spectrometry
|March 15, 2024
概括
负离子电子捕获解离 (niECD) 需要在气态离子中采用zwitterionic结构和紧的盐桥结构,以实现高效的碎片化. 修改来促进zwitterions拯救niECD的能力,确认zwitterion机制和结构要求.
科学领域:
- 质谱测量质量谱测量
- 分析化学 分析化学
- 生物化学 生物化学
背景情况:
- 电子附着在气态离子上使得新的双重质谱 (MS/MS) 技术成为可能.
- 建议负离子电子捕获解离 (niECD) 需要有气态的zwitterionic结构.
- 电子捕获必须发生在正电荷位置或由正电荷位置指导.
研究的目的:
- 为了进一步评估niECD的zwitterion机制.
- 调查有效的niECD的结构要求.
- 评估zwitterionic结构和盐桥形成在niECD效率中的作用.
主要方法:
- 在旨在改变zwitterionic结构形成的衍生上执行niECD.
- 合成的系统研究,具有不同的zwitterion倾向.
- 旅行波离子运动质谱 (TWIMS-MS) 用于分析气相结构.
主要成果:
- 引入固定正电荷,瓜尼迪诺或硫酸盐组在耐火中拯救了niECD的能力.
- 在五个基组中,niECD的效率随着zwitterion倾向的下降而下降.
- TWIMS-MS揭示了碰撞横截面与niECD效率之间的反向相关性,表明需要紧的盐桥结构.
结论:
- 这种zwitterion机制得到了强有力的支持,通过衍生来挽救niECD能力.
- 有效的niECD需要在气相中既有zwitterionic结构,也需要紧的盐桥形状.
- 这些发现为分析中niECD的结构先决条件提供了关键的见解.
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