CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory of Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory of Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
J Chromatogr A. 2022 Aug 16;1677:463319. doi: 10.1016/j.chroma.2022.463319. Epub 2022 Jul 9.
The three-phase solvent system of counter-current chromatography can separate compounds with a wide range of polarity, but there is no study of its separation regularity. Therefore, in this work, the separation regularity of the three-phase solvent system was initially investigated from the perspective of solvent polarities and compound polarities. The standard compounds covering a wide polarity range were selected, and three-phase solvent systems, n-hexane/methyl acetate/acetonitrile/water, and n-hexane/methyl tert-butyl ether/acetonitrile/water were used for modeling. The results showed that in the three-phase solvent system, the partition coefficient for the middle and lower phases (lgK) increased with increasing logP values in three intervals logP < 0, 0 < logP < 4, and logP > 4. In addition, the partition coefficient for the upper and middle phases (lgK) between the upper and middle phases of the small polarity compounds increases with increasing logP values. LogP vs lgK of 7 solvent systems were employed for the smoothing spline fit through a predictive model design of the curve fitting toolbox in MATLAB software, and good results were achieved. LogP versus lgK for n-hexane/methyl tert-butyl ether/acetonitrile/water solvent systems were used for the second-order power fit, and satisfactory results were obtained. The relationship between polarity parameters and separation case parameters was explored using a heat map approach. The separation regularity of the three-phase solvent system was preliminarily investigated. This regularity study gives hope of assistance to the chemists studying three-phase solvents and counter-current chromatography.
逆流色谱三相溶剂系统可以分离具有广泛极性范围的化合物，但目前尚未研究其分离规律。因此，在这项工作中，从溶剂极性和化合物极性的角度初步研究了三相溶剂系统的分离规律。选择了涵盖广泛极性范围的标准化合物，并使用正己烷/乙酸甲酯/乙腈/水和正己烷/叔丁基甲基醚/乙腈/水三相溶剂系统进行建模。结果表明，在三相溶剂系统中，中间相和下相的分配系数（lgK）随三个间隔的logP 值增加而增加：logP<0、0<logP<4 和 logP>4。此外，对于低极性化合物，上相和中间相之间的分配系数（lgK）随 logP 值的增加而增加。使用 7 种溶剂系统的 LogP 与 lgK 通过 MATLAB 软件中曲线拟合工具箱的预测模型设计进行平滑样条拟合，取得了良好的效果。对正己烷/叔丁基甲基醚/乙腈/水溶剂系统的 LogP 与 lgK 进行二次幂拟合，得到了满意的结果。使用热图方法探索了极性参数与分离案例参数之间的关系。初步研究了三相溶剂系统的分离规律。这项规律研究为研究三相溶剂和逆流色谱的化学家提供了帮助的希望。
