对H NMR光谱量化自动分析软件的评估. 信号扩展和EDTA添加的影响
Circe C Hernández-Espino1, Martha E García-Aguilera1, Alan Emmanuel Aguilar Valeriano1
1Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico.
Magnetic resonance in chemistry : MRC
|December 9, 2024
概括
自动化的NMR分析可以错误量化因信号扩展而带有宽信号的葡萄酒化合物. 添加EDTA等合剂或使用无视信号宽度的软件可以提高这些复杂化化合物的精度.
科学领域:
- 分析化学 分析化学
- 食品化学 食品化学
- 频谱学是一种光谱学.
背景情况:
- 核磁共振 (NMR) 对于识别和量化复杂混合物中的化合物至关重要.
- 自动化NMR分析使用光谱库,信号线宽度是关键参数.
- 信号线宽度可以为具有宽信号的复杂化化合物引入度偏差.
研究的目的:
- 用不同的自动化NMR软件评估具有复合活性的七种葡萄酒化合物的量化准确性.
- 评估和化剂 (EDTA) 对量化准确性的影响.
- 为了比较自动化方法与手动解卷.
主要方法:
- 用四个自动化NMR程序和手动解卷方法量化混合物中的七种葡萄酒化合物.
- 分析是在有和没有阳离子存在的情况下进行的.
- 乙二胺四酸盐 (EDTA) 被添加为结合剂,以评估其效果.
- 在葡萄酒样本中使用标准添加剂,有或没有EDTA,量化马拉酸盐.
主要成果:
- 三个使用信号线宽度的自动化程序低估了由于信号扩大而存在子的化合物度.
- 添加EDTA可以减轻由信号扩大引起的低估误差.
- 无需利用信号线宽度的自动化软件,无论有没有阴子存在,都能提供一致的量化.
- 与自动化方法相比,手动解卷结果没有明确详细说明.
结论:
- 复杂化化合物的自动化NMR量化可以因在子存在时的信号扩展而被偏差.
- 像EDTA这样的化剂可以纠正信号扩展引起的错误.
- 算法选择和样本准备对于精确的复杂化化合物的自动分析至关重要.
- 未来的NMR软件应该允许灵活调整信号线宽度,以提高准确性.
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