Clindamycin phosphate-based deep eutectic solvent as a chiral selector for enantioseparation of amino alcohol drugs in nonaqueous capillary electrophoresis

Clindamycin phosphate (CP) exhibits good enantioselectivity for many basic drugs, but its separation effect for most amino alcohol drugs is not satisfactory. In this work, a deep eutectic solvent (DES) chiral selector based on CP was prepared for the first time and utilized as a single chiral selector in nonaqueous capillary electrophoresis (NACE) to separate twelve amino alcohol drugs. Compared with unmodified CP, the separations of model drugs in the DES chiral selector system were significantly improved. Most amino alcohol drugs could be completely separated, and the peak shapes were good. In addition, we used infrared spectroscopy and nuclear magnetic resonance method to study the specific separation mechanism and explored the reasons why DES chiral selector has better enantioselectivity. This work is the first to directly modify antibiotic chiral selector into DES, indicating a direction for us to develop novel chiral recognition materials.