Izumoto S, Nishi H
Tanabe Seiyaku Co., Ltd., Analytical Research Laboratory, Osaka, Japan.
Electrophoresis. 1999 Jan;20(1):189-97. doi: 10.1002/(SICI)1522-2683(19990101)20:1<189::AID-ELPS189>3.0.CO;2-7.
Direct separation of enantiomers of drugs was investigated by capillary electrophoresis employing mixtures of charged cyclodextrin derivatives (CDs) and electrically neutral CDs (i.e., dual CD system). Among various charged CDs employed, it was found that beta-CD sulfate showed relatively wide enantioselectivity for a wide variety of drugs under acidic conditions. Then separation of enantiomers was performed by employing beta-CD sulfate and the effect of the addition of electrically neutral CDs to the buffers containing beta-CD sulfate was investigated. Through the addition of electrically neutral CDs to the buffers containing the charged CD, resolution of most of the enantiomers was improved, compared with those with the charged CD alone. It was also found that the ring size (alpha, beta, gamma,), the substitution groups and the concentration of the additional electrically neutral CDs affected the enantioselectivity. For example, alpha-CD addition was effective for the separation of enantiomers of chlorpheniramine and hydroxypropyl-beta-CD was effective for the enantiomer separation of trimetoquinol isomer. The application of the method in optical purity testing is also briefly mentioned.
采用带电荷的环糊精衍生物（CDs）和电中性CDs的混合物（即双CD体系），通过毛细管电泳研究了药物对映体的直接分离。在所使用的各种带电荷的CDs中，发现硫酸β-CD在酸性条件下对多种药物表现出相对较宽的对映体选择性。然后采用硫酸β-CD进行对映体分离，并研究了向含有硫酸β-CD的缓冲液中添加电中性CDs的效果。通过向含有带电荷CD的缓冲液中添加电中性CDs，与单独使用带电荷CD相比，大多数对映体的拆分效果得到了改善。还发现环糊精的环大小（α、β、γ）、取代基以及添加的电中性CDs的浓度会影响对映体选择性。例如，添加α-CD对氯苯那敏对映体的分离有效，添加羟丙基-β-CD对曲美喹诺异构体的对映体分离有效。还简要提及了该方法在光学纯度检测中的应用。
