化学试剂

建立了核磁共振氢谱法(~1HNMR)测定6种香精化合物(香豆素、香兰素、甲基香兰素、乙基香兰素、麦芽酚、乙基麦芽酚)纯度的定值方法。选择合适的溶剂、内标，通过测定样品的定量信号的纵向弛豫时间(T₁)来计算准确定量所需的理论弛豫时间(D₁),比较样品在不同弛豫时间下测得的实际纯度来对D₁进行优化的数据，实验结果显示两种D₁优化方法结果一致。分析样品中每个合适的定量信号所得到的定值结果并找到定值结果差异的原因。最终6种样品的纯度结果分别为99.79%、99.80%、99.78%、99.82%、99.86%、99.53%,扩展不确定度(k=2)分别为0.16%、0.10%、0.22%、0.18%、0.14%、0.14%。其不仅适用于香豆素等香精化合物的含量测定，在弛豫时间及定量峰的确定方面也适用于其他化合物，以确保更精确的定值。

A method of ~1H nuclear magnetic resonance(~1HNMR) was established for the purity determination of six kinds of fragrance compounds(coumarin, vanillin, methyl vanillin, ethyl vanillin, maltol, and ethyl maltol).Suitable solvents and internal standards were selected, and the theoretical relaxation time(D₁) required for accurate quantification was calculated by measuring the longitudinal relaxation time(T₁) of the quantification signal of samples.Comparing the purity of samples at different relaxation times to optimize the data for D₁,the experimental results showed that the two methods of optimization of D1 were consistent.The fixation results obtained for each of the appropriate quantitative signals were analyzed to find the reasons for the differences.The final purity results of six samples were 99.79%,99.80%,99.78%,99.82%,99.86% and 99.53%,respectively, with extended uncertainty(k=2) of 0.16%,0.10%,0.22%,0.18%,0.14%,and 0.14%.The method not only is suitable for determining the content of fragrance compounds such as coumarin, but also for determining relaxation time and selecting suitable quantitative peaks for other compounds to ensure a more accurate purity determination.