在液滴中快速交换
Erik T Jansson1,2, Yin-Hung Lai2, Juan G Santiago3
1Department of Chemistry-BMC, Uppsala University , SE-751 24 Uppsala, Sweden.
Journal of the American Chemical Society
|May 9, 2017
概括
这项研究使用质谱测量水滴中的-交换 (HDX) 速率,发现与散装溶液相比,水滴中的HDX显著加快. 这种技术为研究分子动力学提供了微秒分辨率.
科学领域:
- 分析化学
- 物理化学
- 生物物理化学
背景情况:
- -交换 (HDX) 是研究分子动力学和结构的关键技术.
- 对于快速交换过程,传统的方法如停止流动力学和NMR光谱学在时间分辨率上有局限性.
- 在微滴中研究HDX提供了一种新的方法来探测具有高时间分辨率的快速化学反应.
研究的目的:
- 为了确定-交换率 (HDX) 在乙的水滴中,时间分辨率小于毫秒.
- 研究滴滴封闭和微环境对HDX率的影响.
- 将液滴中的HDX率与散装溶液中测量的水平进行比较.
主要方法:
- 使用纳米电子喷雾电离与甲毛细血管产生水滴.
- 采用质谱测量以获得小于百万秒的时间分辨率.
- 使用微粒图像速度测量微粒速度.
- 使用普通微分方程系统建模的HDX动力学.
主要成果:
- 与批量测量相比,观察到水滴中的HDX速率加快.
- 乙胺HDX的确定速率常量为: -NH2D+形成的3660±290秒, -NH2+形成的3330±270秒.
- 在液滴和大量溶液中发现了7倍的HDX对血管素I的加速.
- 在运行时间内,已证明滴滴加速率约为30%.
结论:
- HDX在水滴中比在散装溶液中发生的速度要快得多,这表明受限效应会影响反应速度.
- 毛细胞方法使快速交换过程的快速混合和高吞吐量分析成为可能.
- 这种技术为研究分子动力学和动力学提供了强大的工具,
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