1D NOESY的基本准确性与使用氨基和酸标准溶液的预和方法
1Center for Environmental Standards and Measurement, Health and Environmental Risk Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan. saito-naoki@nies.go.jp.
Analytical and bioanalytical chemistry
|August 23, 2024
概括
通过预和 (NOESY-presat) 优化核过重效应光谱 (NOESY) 对于精确的度测量至关重要. 调整混合时间和频率偏差可以显著减少偏差,从而改善定量分析.
科学领域:
- 分析化学 分析化学
- 生物物理化学 生物物理化学
- 频谱学是一种光谱学.
背景情况:
- 1D NOESY与预和 (NOESY-presat) 是一种在NMR光谱学中广泛使用的抑制水的技术.
- 使用NOESY-presat的定量分析可能会受到度偏差的影响,特别是在不同的实验参数下.
研究的目的:
- 为了调查和最小化定量核过量效应光谱 (NOESY) 实验中的度偏差.
- 评估标准NOESY-presat和一种新的NOESY-双presat方法的性能.
主要方法:
- 用NOESY-presat.使用L-氨酸和L-氨酸的D2O溶液进行测量.
- 评估了混合和演化时间对度偏差的影响.
- 通过调整频率偏移来解决异共振效应.
- 提出了一种新的NOESY双预制方法,并与NOESY预制方法进行了比较.
主要成果:
- 在NOESY-presat中,绝对度偏差随着混合/演化时间的延长而增加,高达54%.
- 在0ms混合和0μs演变时间下,偏差减少到<3%.
- 在H2O/D2O溶液中,NOESY-presat显示了26% (甘氨酸) 和11% (酸) 的偏差.
- NOESY-双预设方法将偏差降低到<4%,尽管最初的水抑制不足.
结论:
- 精心优化混合时间和频率偏移对于使用NOESY-presat. 精确的定量分析至关重要.
- NOESY-双预测方法提供了更好的准确性,但需要优化压水.
- 了解和减轻非共振效应对于可靠的基于NOESY的度测量至关重要.
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