相关实验视频

Updated: Jan 16, 2026

Pure Shift Nuclear Magnetic Resonance: a New Tool for Plant Metabolomics

Pure Shift Nuclear Magnetic Resonance: a New Tool for Plant Metabolomics

Published on: July 31, 2021

黑茶的H NMR纯转移代谢分析

Han Wang¹, Laura Castañar^1,2, Ralph W Adams¹

¹Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.

Analytical chemistry

|September 26, 2025

概括

纯转移NMR增强了代谢分析的分辨率,尽管灵敏度较低,但提供了与传统方法相比的黑茶品种歧视. 结合技术有助于复杂样本中的信号分配.

科学领域:

分析化学分析化学
代谢学代谢学代谢学
核磁共振 (NMR) 光谱学核磁共振 (NMR) 光谱学

背景情况:

纯转移NMR通过抑制同核标尺合来提高光谱分辨率.
与传统的NMR相比,这种增强是以降低灵敏度为代价的.
非定位代谢分析依赖于高分辨率光谱来准确识别和区分化合物.

研究的目的:

为了比较不同纯转移NMR方法与传统的1D¹H和2DJ解析NMR的有效性,进行非目标代谢分析.
评估增强光谱分辨率对黑茶品种与不同品种的歧视的影响.
评估将纯转移NMR技术与2D J解析实验相结合的实用性,以简化复杂代谢数据集中的信号分配.

主要方法:

使用各种纯转移核磁共振技术 (包括PSYCHE) 和常规1D¹H和2DJ解析核磁共振技术获得的非目标代谢组数据的比较.
来自两个不同的品种的黑茶样本的分析.
将多变量统计分析应用于用于样本歧视的光谱数据.

主要成果:

纯转移核磁共振实验,尽管灵敏度较低,但黑茶品种的歧视与传统的1D1H核磁共振相提并论.
多变量分析证实了纯转移NMR在区分茶叶品种方面的稳定性.
2DJ解析和PSYCHE光谱的组合显著简化了信号分配,这是代谢学中的关键步骤.

结论:

增强分辨率纯转移NMR是一种可行的和有效的技术,用于非目标代谢分析,提供有价值的歧视能力.
纯轮换NMR中灵敏度和分辨率之间的权衡对于某些应用,如品种歧视,是可以管理的.
整合互补的NMR技术,如2D J-resolved和PSYCHE,可以增强数据解释,加快新陈代谢工作流.

更多相关视频

Author Spotlight: Exploring Tea Aroma Using Solvent-Assisted Flavor Evaporation Technique

Author Spotlight: Exploring Tea Aroma Using Solvent-Assisted Flavor Evaporation Technique

Published on: May 26, 2023

Quantitative 31P NMR Analysis of Lignins and Tannins

Quantitative 31P NMR Analysis of Lignins and Tannins

Published on: August 2, 2021

相关概念视频

NMR Spectroscopy: Chemical Shift Overview

NMR Spectroscopy: Chemical Shift Overview

The position of the absorption signal of a sample is reported relative to the position of the signal of tetramethylsilane (TMS), which is added as an internal reference while recording spectra. The difference between the absorption frequencies of the sample and TMS (in Hz) is divided by the spectrometer operating frequency (in MHz) to obtain a dimensionless quantity called the chemical shift. It is reported on the δ (delta) scale and expressed in parts per million.
For instance, the proton...

Proton (¹H) NMR: Chemical Shift

Proton (¹H) NMR: Chemical Shift

Organic molecules primarily contain carbon and hydrogen atoms. While all the hydrogen isotopes are NMR-active, protium or hydrogen-1 is the most abundant. It has a significant energy separation between its nuclear spin states due to its large gyromagnetic ratio. As per Boltzmann's distribution, an increase in the energy separation implies a greater excess population of nuclei available for excitation, resulting in a strong NMR absorption signal.
Absorption signals of all the protium nuclei...

¹H NMR Chemical Shift Equivalence: Enantiotopic and Diastereotopic Protons

¹H NMR Chemical Shift Equivalence: Enantiotopic and Diastereotopic Protons

Replacing each alpha-hydrogen in chloroethane by bromine (or a different functional group) yields a pair of enantiomers. Such protons are called prochiral or enantiotopic and are related by a mirror plane. Enantiotopic protons are chemically equivalent in an achiral environment. Because most proton NMR spectra are recorded using achiral solvents, enantiotopic hydrogens yield a single signal.
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...

¹H NMR of Labile Protons: Temporal Resolution

¹H NMR of Labile Protons: Temporal Resolution

Protons bonded to heteroatoms such as nitrogen and oxygen exhibit a range of chemical shift values. This is due to the varying degree of hydrogen bonding between the proton and the heteroatom in other molecules. The extent of hydrogen bonding affects the electron density around the proton, thereby giving different chemical shift values for the protons in the proton NMR spectrum.
The –OH proton in alcohols typically appears in the range of δ 2 to 5 ppm but can vary depending on the specific...

Carbon-13 (¹³C) NMR: Overview

Carbon-13 (¹³C) NMR: Overview

Carbon-13 is a naturally occurring NMR-active isotope of carbon with a low natural abundance of 1.1%. In contrast, carbon-12 is the most abundant isotope of carbon with zero nuclear spin. Therefore, it is NMR inactive. The gyromagnetic ratio of carbon-13 is smaller than that of protons. As a result, carbon-13 resonance is about 6000 times weaker than proton resonance. For a given magnetic field strength, the resonance frequency of carbon-13 is about one-fourth of the resonance frequency for...

¹H NMR: Interpreting Distorted and Overlapping Signals

¹H NMR: Interpreting Distorted and Overlapping Signals

Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...