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CPMG脉冲序列用于放松分散,可以取消独立于旋转状态的工件

Tsuyoshi Konuma¹, Jun-Ichi Kurita¹, Takahisa Ikegami¹

¹Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.

Journal of magnetic resonance (San Diego, Calif. : 1997)

|May 29, 2023

概括

一个新的核磁共振脉冲序列,AFTAC,有效地抑制了小分子放松分散实验中的工件. 这种方法通过准确捕捉两个磁化组件而改善了热力学和动力学分析,而不需要质子脱.

科学领域:

核磁共振光谱学核磁共振光谱学
化学动力学和热力学.

背景情况:

核磁共振 (NMR) 放松分散 (rd) 实验为交换分子构造提供了关键的热力学和动力学数据.
标准的Carr-Purcell-Meiboom-Gill (CPMG) 脉冲序列通常会在异核S旋转系统 (SI,SI3) 中引入人工物,原因是放松率的平均值不完整.
这些文物,特别是当CPMG被异质核单量子相关联 (HSQC) 之后出现问题时,会影响两个S-旋转双重磁化组件之一的信号检测.

研究的目的:

开发一种用于NMR放松分散的新型脉冲序列,克服现有CPMG方法的器件限制.
通过抑制两个磁化组件中的工件来实现小分子的精确热力学和动力学测量.

主要方法:

开发了一种新的脉冲序列,命名为AFTAC (无文物双组件获取).
通过计算模拟和实验测量对二甲基硫化物和N,N-二甲基三乙胺甲基组的验证.
应用于SI,SI2和SI3旋转系统.

主要成果:

AFTAC序列有效地抑制了S-旋转磁化组件中的两种器件的工件,即使与HSQC序列相结合.
模拟和实验数据证实了AFTAC.的文物抑制能力.
该方法在SI,SI2和SI3旋转系统中显示出一致的性能.

结论:

在NMR放松分散中,AFTAC为人工物抑制提供了强大的解决方案,特别是对于对TROSY不敏感的小,非化分子.
该序列消除了对1H连续波辐射的需求,减少了实验负载和探头负载,特别是对于长T_cpmg值.
AFTAC提高了从放松分散研究中获得的热力学和动力学数据的可靠性.

关键词:

卡尔 - 普塞尔 - 梅布姆 - 吉尔 (CPMG) 脉冲列车核磁共振 (NMR) 是一种核磁共振技术.非共振效应的效应脉冲不完美是因为脉冲不完美.放松分散的放松.

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