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通过放松工程和信号对噪声效率指标,优化了对复杂混合物的C qNMR

Qi Tang^1,2,3, Sinan Wang¹, Jun Li⁴

¹Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.

Analytical chemistry

|November 18, 2025

概括

这项研究通过减少采集时间和提高灵敏度来优化碳-13定量NMR (C qNMR). 新方法为复杂混合物提供可靠的量化,改善分析化学应用.

科学领域:

分析化学分析化学
频谱学是一种光谱学.
自然产品分析自然产品分析

背景情况:

复杂混合物的定量分析由于当前方法的局限性而具有挑战性.
碳-13定量NMR (C qNMR) 具有较长的采集时间和较低的灵敏度.

研究的目的:

开发一个优化的C qNMR方法,以应对长时间的采集时间和低灵敏度.
为合理的参数选择引入信号对噪声效率系数 (η).
建立一个强大的,独立于参考材料的C qNMR平台.

主要方法:

添加一个偏磁性放松剂,以减少13C纵向放松时间 (T1).
开发和应用一个信号对噪声效率系数 (η = SNR2/T) 进行优化.
使用 η.的样本度和扫描次数 (NS) 的因数评估.

主要成果:

在C T1放松时间中实现了高达95%的减少,导致总获取时间减少65%.
建立了优化的采集条件,最大限度地减少样品消耗,最大限度地提高效率.
在分析Panax notoginseng提取物中的氨酸时,证明了出色的定量可靠性 (<1%的偏差与HPLC-UV相比).

结论:

优化的C qNMR方法大大提高了速度和灵敏度.
新的e因子为平衡NMR实验持续时间和灵敏度提供了定量指标.
这种先进的C qNMR平台是分析复杂的自然,生物和环境混合物的通用工具.

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