Mazzeo J R, Grover E R, Swartz M E, Petersen J S
Waters Chromatography, Milford, MA 01757.
J Chromatogr A. 1994 Sep 30;680(1):125-35. doi: 10.1016/0021-9673(94)80060-X.
A novel chiral surfactant was prepared as both enantiomeric forms, (R)- and (S)-N-dodecoxycarbonylvaline, and employed for the separation of enantiomeric mixtures by micellar electrokinetic capillary chromatography (MECC). The enantioselectivities (alpha) obtained for twelve typical pharmaceutical amines using the (S)-surfactant were compared to those obtained with (S)-N-dodecanoylvaline, a chiral surfactant described in the literature. Higher enantioselectivities were seen for ten of the twelve compounds using (S)-N-dodecoxycarbonylvaline. Furthermore, (S)-N-dodecoxycarbonylvaline had significantly less background absorbance in the low UV. It is shown that exact enantiomer migration order reversal can be obtained by individually employing both enantiomeric forms of the surfactant. For ionizable compounds like the amines examined here, enantioselectivity can be optimized by changing the pH of the MECC buffer. Partitioning is optimized through surfactant concentration, organic additives and pH. The ability to achieve fast chiral separations is shown. A separation of ephedrine enantiomers in urine is shown, with the only sample preparation being filtration.
制备了一种新型手性表面活性剂，即对映体形式的（R）-和（S）-N-十二烷氧基羰基缬氨酸，并将其用于通过胶束电动毛细管色谱法（MECC）分离对映体混合物。将使用（S）-表面活性剂对十二种典型药物胺获得的对映体选择性（α）与文献中描述的手性表面活性剂（S）-N-十二烷酰缬氨酸获得的对映体选择性进行了比较。使用（S）-N-十二烷氧基羰基缬氨酸时，十二种化合物中的十种表现出更高的对映体选择性。此外，（S）-N-十二烷氧基羰基缬氨酸在低紫外光下的背景吸光度明显更低。结果表明，分别使用表面活性剂的两种对映体形式可以实现对映体迁移顺序的精确反转。对于此处研究的胺类等可电离化合物，可以通过改变MECC缓冲液的pH值来优化对映体选择性。通过表面活性剂浓度、有机添加剂和pH值优化分配。展示了实现快速手性分离的能力。展示了尿液中麻黄碱对映体的分离，唯一的样品制备步骤是过滤。
