Polyamidoamine dendrimers as off-column binding agent and in-column pseudostationary phase for efficient and sensitive capillary electrophoretic analysis of fluoroquinolones in chicken muscles

• Polyamidoamine generation 0.5 as binding agent in fluoroquinolone sample solution.
• Polyamidoamine generation 0 in mild alkaline buffer as pseudostationary phase.
• The hyphenated strategy provided 10–32 folds improvement in detection sensitivity.
• The approach is applicable for quick assaying fluoroquinolones in real samples.

A capillary electrophoresis method based on polyamidoamine dendrimers has been developed for quick and sensitive detection of moxifloxacin, gatifloxacin, lomefloxacin, enoxacin, ofloxacin and pazufloxacin. Increasing buffer alkalinity led to enhanced sensitivity, whereas the polyamidoamine–fluoroquinolone interactions, i.e., in-cavity hydrogen bonding/hydrophobic interaction and electrostatic interaction, contributed to the improvement in both separation efficiency and detection sensitivity. By using 1 mM polyamidoamine generation 0.5 as binding agent in sample solution and 0.1 μM polyamidoamine generation zero as pseudostationary phase to the running buffer of 5 mM sodium tetraborate at pH 9.3, the six fluoroquinolones were baseline separated in <10 min with detection limits at ng/mL level. Coupled with liquid–liquid extraction, the proposed method was successfully applied in the determination of fluoroquinolones in chicken muscle samples.