在电子喷射电离过程中揭示神经八度数集群形成的途径:实验和模拟
Vida Alinezhad1, Yuen Ki Ng1, Sanvid Mehta1
1Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada.
Journal of the American Chemical Society
|September 17, 2024
概括
在电喷离 (ESI) 过程中,Serine (Ser) 形成了一个稳定的魔数集群,Ser8H+. 这项研究揭示了Ser8H+在离子采样过程中通过集群解离而不是溶液中的形式,这解释了其独特的丰富性.
科学领域:
- 分析化学
- 物理化学
- 生物物理化学
背景情况:
- 电子喷射电离 (ESI) 通常会产生不特定的集群.
- 氨酸 (Ser) 独特地形成了大量的神奇数组,Ser8H+,但其形成机制和位置尚不清楚.
- 之前的研究已经讨论了Ser8H+是否在溶液中或ESI过程中形成.
研究的目的:
- 为了阐明神奇数组l-Ser8H+的形成路径.
- 研究离子采样条件在Ser8H+形成中的作用.
- 为了使观察到的Ser8H+的丰度与其低串联质谱 (MS/MS) 稳定性相协调.
主要方法:
- 血清溶液的电子喷射电离 (ESI).
- 在恶劣的离子采样条件下进行碰撞诱导解离 (CID) 实验.
- 移动质子分子动力学模拟.
- 离子运动实验.
主要成果:
- 在离子采样过程中发现了Ser8H+的形成,而不是溶液中.
- ESI滴蒸发,释放非特异性的Ser,在离子采样过程中分离.
- 这些集群的子群在八合体水平结束解离,形成Ser8H+.
- 模拟的Ser8H+结构与实验中的离子流动性数据相匹配,显示具有盐桥和H键的紧形式.
结论:
- 通过在离子采样过程中涉及集群解离的途径形成神奇数集群Ser8H+.
- ESI条件和集群分离动态决定了八位数级的终结.
- 这项研究通过跨相界的关联和离散反应的相互作用来阐明魔数集群的形成.
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