A comprehensive study into the effects of mobile phase composition and column temperature on enantiomer elution order was conducted with a set of chiral rod-like liquid crystalline materials. The analytes were structurally similar and comprised variances such as length of terminal alkyl chain, presence of chlorine, number of phenyl rings, and type of chiral center. Experiments were carried out in polar organic and reversed-phase modes using amylose tris(3-chloro-5-methylphenylcarbamate) immobilized on silica gel as the chiral stationary phase. For all liquid crystals, reversal of elution order of enantiomers was observed based on type of used cosolvent and/or its content in the mobile phase; for some of the liquid crystals a temperature-induced reversal was also observed. Both linear and nonlinear dependencies of natural logarithm of enantioselectivity on temperature were found. Tested mobile phases comprised pure organic solvents and binary and tertiary mixtures of acetonitrile with organic solvents and/or water. Effect of acidic/basic mobile phase additives was also tested. Effect of structure of chiral selector is briefly discussed.

中文翻译：

---

流动相组成和柱温如何影响作为手性选择剂的直链淀粉三（3-氯-5-甲基苯基氨基甲酸酯）液晶的对映体洗脱顺序

使用一组手性棒状液晶材料对流动相组成和柱温对对映体洗脱顺序的影响进行了综合研究。分析物在结构上相似，并且包含差异，例如末端烷基链的长度、氯的存在、苯环的数量和手性中心的类型。使用固定在硅胶上的直链淀粉三（3-氯-5-甲基苯基氨基甲酸酯）作为手性固定相，以极性有机和反相模式进行实验。对于所有液晶，根据所用助溶剂的类型和/或其在流动相中的含量，观察到对映异构体的洗脱顺序颠倒；对于一些液晶，还观察到温度引起的反转。发现了对映选择性的自然对数对温度的线性和非线性依赖性。测试的流动相包括纯有机溶剂和乙腈与有机溶剂和/或水的二元和三元混合物。还测试了酸性/碱性流动相添加剂的影响。简要讨论了手性选择器结构的影响。