逆流色谱溶质出峰顺序的预测

Prediction of Eluotropic Sequence of Solutes in Countercurrent Chromatography

根据逆流色谱保留方程可知,溶质的出峰顺序主要取决于其在互不混溶的两液相间分配系数的大小顺序。以饱和及不饱和脂肪酸乙酯、2,4 二硝基苯胺基脂肪醇和对硝基苯基葡萄糖甙等结构较为简单、极性差别较大的溶质系列为研究对象,应用修正的通用基团活度系数(UNIFAC)(Dortmund)模型,通过相平衡计算,预测了它们在含水或不含水的溶剂体系中分配系数的变化趋势,并与前人的工作进行了对比。结果表明,由该方法预测出的相似结构溶质分配系数的顺序基本上与实验值相同,其中对饱和脂肪酸乙酯在己烷 乙腈(体积比为1∶1)体系中分配系数的预测最好。这种预测方法的建立将对逆流色谱非电解质溶剂体系的选择具有较大的指导意义。

According to the retention equation of countercurrent chromatography (CCC), the eluotropic sequence of solutes depends mainly on the order of their partition coefficients between the two immiscible liquid phases. The varying tendencies of partition coefficients of some compounds in aqueous or nonaqueous solvent systems by calculating the phase equilibria with universal quasichemical functional group activity coefficient (UNIFAC) (Dortmund) model are predicted. These compounds included saturated and unsaturated fatty acids ethyl esters, N2,4dinitrophenylamino alcohols, pnitrophenyl glucosides and so on, with simple structures and much differences in polarity. It has been found that the predicted tendencies of partition coefficients of the analogues were consistent with the experimental ones reported in literature, and the best results were obtained for saturated fatty acid ethyl esters in hexaneacetonitrile (1∶1 in volume ratio) solvent system. The establishment of a method for prediction will be helpful for the selection of nonelectrolyte solvent systems in CCC. 