Abstract A new method for the determination of three different classes of secondary metabolites (flavonoids, iridoids and phenylpropanoids) present in extracts of Lippia alba leaves based on CE is described. The capillary electrophoretic separation of these compounds was possible employing a 50 mM borax buffer containing 75 mM SDS and 5% isopropanol as organic modifier. The analytes could be well resolved in 25 min and accurately determined in different chemotypes of Lippia alba specimens. Method validation assured the compliance of the assay to International Conference on Harmonization standards (ICH) (correlation coefficients ≥0.9944, LOD 23.0–65.0 μg ml−1 and LOQ 38.0–119.0 μg ml−1, recovery rates from 97 to 101%, intermediate precision ≤2.1%, and repeatability ≤5.0%). The proposed method was compared with a previously validated HPLC method using eight samples as well as by statistical means (t-test). In all the samples, T calculated was less than T critical with a significance level of 5%, thus demonstrating that CE is a good alternative for the separation and quantification of polar compounds in plant extracts.

中文翻译：

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胶束电动毛细管色谱法同时测定白杨树提取物中环烯醚萜、苯丙烷和黄酮类化合物

摘要 描述了一种基于 CE 测定白杨叶提取物中存在的三种不同类别次生代谢物（黄酮类、环烯醚萜类和苯丙烷类）的新方法。使用含有 75 mM SDS 和 5% 异丙醇的 50 mM 硼砂缓冲液作为有机改性剂，可以对这些化合物进行毛细管电泳分离。分析物可以在 25 分钟内得到很好的分离，并在不同化学类型的 Lippia alba 标本中准确测定。方法验证确保检测符合国际协调标准 (ICH)（相关系数 ≥ 0.9944，LOD 23.0–65.0 μg ml-1 和 LOQ 38.0–119.0 μg ml-1，回收率从 97% 到 101%，中等精度≤2.1%，重复性≤5.0%）。所提出的方法与使用八个样品以及通过统计方法（t 检验）的先前验证的 HPLC 方法进行了比较。在所有样品中，计算的 T 均小于 T 临界值，显着性水平为 5%，因此证明 CE 是分离和定量植物提取物中极性化合物的良好替代方案。