Separation of ofloxacin enantiomers by CE with fluorescence detection using DNA oligonucleotides as chiral selectors

This study used CE with fluorescence detection- and partial-filling mode-based method for chiral separation of ofloxacin. The DNA oligonucleotides with different base sequences were studied as potential chiral selectors including DNA tetrahedron, G-quadruplex, and G-riched double-strand DNA. Under the optimized conditions, all the DNA chiral selectors exhibited excellent chiral separation capabilities with a resolution higher than 1.5. The electrophoretic behavior of the ofloxacin enantiomer might result from the intermediate conjugate with different stabilities between chiral selectors and analytes by a combination of the hydrogen bond and spatial recognition structure. Moreover, satisfactory repeatability regarding run-to-run and interday repeatability was obtained, and all the RSD values of migration times and resolutions were below 4% (n = 6). Conclusively, both spatial structure and arrangement of the G bases potentiated the chiral separation capability of DNA for ofloxacin enantiomer. This work offered a stepping stone for enantioseparation using DNA as chiral selectors. This article is protected by copyright. All rights reserved.