Doxycycline as a new chiral selector in capillary electrophoresis

- Doxycycline was evaluated as a chiral selector for enantioseparation by CE.
- Effects of separation conditions for acidic chiral analytes were investigated.
- Optimal conditions for chiral separation were found.

Doxycycline (DOX) is one of the tetracycline class of antibiotics and has not been examined for its enantioseparation abilities previously. The purpose of the present work was to evaluate DOX as a chiral selector (CS) using capillary electrophoresis (CE) in nonaqueous mode. Systematic experiments were performed to investigate the effects of concentration of CS, compositions of organic solvents and background electrolytes, applied voltage on chiral separation of a set of acidic chiral compounds. Excellent resolutions of enantiomers of acidic chiral compounds were attained in a background electrolytes composed of 50:50 acetonitrile/methanol + 214 mM acetic acid+ 63 mM triethylamine and 38 mM DOX. The results show that DOX is a viable chiral selector in CE for the enantioseparation of the type of chiral compounds investigated.