Quick and Sensitive Determination of Fluoroquinolones by Capillary Electrophoresis–Potential Gradient Detection

Abstract

A rapid, capillary electrophoresis–potential gradient detection method was developed for determining three fluoroquinolones: rufloxacin, enoxacin, and moxifloxacin. The fluoroquinolones were baseline separated within 3.5 min with background electrolyte composed of 50 mM acetic acid and 6 mM potassium hydroxide at pH 3.7. For the first time, electrokinetic injection was applied in capillary electrophoretic separation of fluoroquinolones, and an average of ca. 10-fold improvement in detection limits was observed. The method was applied to a fortified chicken tissue sample with detection limits (S/N = 3) of 22–24 ng g⁻¹, suggesting the potential of the method for determining fluoroquinolone residues in real samples.

Keywords:

• Capillary electrophoresis
• chicken tissues
• electrokinetic injection
• fluoroquinolones
• potential gradient detection

Acknowledgments

This work was supported by the National Natural Science Foundation of China (Nos. 20575009 and 20775008), the Beijing Program Foundation for Excellent Talents (No. 20061D0503100307), and the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry.

Notes

^a LOD was defined as the signal-to-noise ratio of 3.

^b LOQ was defined as the signal-to-noise ratio of 10.