Wistuba D, Cabrera K, Schurig V
Institute for Organic Chemistry, University of Tübingen, Germany.
Electrophoresis. 2001 Aug;22(12):2600-5. doi: 10.1002/1522-2683(200107)22:12<2600::AID-ELPS2600>3.0.CO;2-H.
Native beta- and gamma-cyclodextrin bound to silica (ChiraDex-beta and ChiraDex-gamma) were packed into capillaries and used for enantiomer separation by capillary electrochromatography (CEC) under aqueous and nonaqueous conditions. Negatively charged analytes (dansyl-amino acids) were resolved into their enantiomers by nonaqueous CEC (NA-CEC). The addition of a small amount of water to the nonaqueous mobile phase enhanced the enantioselectivity but increased the elution time. The choice of the background electrolyte (BGE) determined the direction of the electroosmotic flow (EOF). With 2-(N-morpholino) ethanesulfonic acid (MES) or triethylammonium acetate (TEAA) as BGE an inverse EOF (anodic EOF) was observed while with phosphate a cathodic EOF was found. The apparent pH (pH*), the concentration of the BGE, and the nature of the mobile phase strongly influenced the elution time, the theoretical plate number and the chiral separation factor of racemic analytes.
将与硅胶结合的天然β-和γ-环糊精（ChiraDex-β和ChiraDex-γ）填充到毛细管中，并用于在水性和非水性条件下通过毛细管电色谱（CEC）进行对映体分离。带负电荷的分析物（丹磺酰氨基酸）通过非水CEC（NA-CEC）拆分为其对映体。向非水流动相中加入少量水可提高对映选择性，但会延长洗脱时间。背景电解质（BGE）的选择决定了电渗流（EOF）的方向。以2-（N-吗啉代）乙磺酸（MES）或三乙胺乙酸盐（TEAA）作为BGE时，观察到反向EOF（阳极EOF），而以磷酸盐作为BGE时，则发现阴极EOF。表观pH（pH*）、BGE的浓度以及流动相的性质强烈影响外消旋分析物的洗脱时间、理论塔板数和手性分离因子。
