Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, USA.
Phytochem Anal. 2013 Nov-Dec;24(6):581-97. doi: 10.1002/pca.2436. Epub 2013 Jun 5.
Nuclear magnetic resonance (NMR) spectroscopy is increasingly employed in the quantitative analysis and quality control (QC) of natural products (NP) including botanical dietary supplements (BDS). The establishment of QC protocols based on quantitative (1) H NMR (qHNMR) requires method validation.
Develop and validate a generic qHNMR method. Optimize acquisition and processing parameters, with specific attention to the requirements for the analysis of complex NP samples, including botanicals and purity assessment of NP isolates.
In order to establish the validated qHNMR method, samples containing two highly pure reference materials were used. The influence of acquisition and processing parameters on the method validation was examined, and general aspects of method validation of qHNMR methods discussed. Subsequently, the method established was applied to the analysis of two NP samples: a purified reference compound and a crude mixture.
The accuracy and precision of qHNMR using internal or external calibration were compared, using a validated method suitable for complex samples. The impact of post-acquisition processing on method validation was examined using three software packages: TopSpin, Mnova and NUTS. The dynamic range of the qHNMR method developed was 5000:1 with a limit of detection (LOD) of better than 10 µm. The limit of quantification (LOQ) depends on the desired level of accuracy and experiment time spent.
This study revealed that acquisition parameters, processing parameters and processing software all contribute to qHNMR method validation. A validated method with a high dynamic range and general workflow for qHNMR analysis of NP is proposed.
核磁共振（NMR）光谱技术在天然产物（NP）的定量分析和质量控制（QC）中应用越来越广泛，包括植物性膳食补充剂（BDS）。基于定量（1）H NMR（qHNMR）的 QC 协议的建立需要方法验证。
开发和验证一种通用的 qHNMR 方法。优化采集和处理参数，特别注意分析复杂 NP 样品的要求，包括植物药和 NP 分离物的纯度评估。
为了建立经过验证的 qHNMR 方法，使用了两种高纯度参考物质的样品。考察了采集和处理参数对方法验证的影响，并讨论了 qHNMR 方法验证的一般方面。随后，将建立的方法应用于两种 NP 样品的分析：一种纯化的参考化合物和一种粗混合物。
使用内部或外部校准比较了 qHNMR 的准确性和精密度，使用适合复杂样品的经过验证的方法。使用三个软件包（TopSpin、Mnova 和 NUTS）考察了采集后处理对方法验证的影响。所开发的 qHNMR 方法的动态范围为 5000:1，检测限（LOD）优于 10 µm。定量限（LOQ）取决于所需的准确度水平和实验时间。
本研究表明，采集参数、处理参数和处理软件都有助于 qHNMR 方法验证。提出了一种经过验证的、具有高动态范围和一般 NP qHNMR 分析工作流程的方法。
