Separation of fluoroquinolones in acidic buffer by capillary electrophoresis with contactless conductivity detection.

A method to determine five fluoroquinolones (FQs), namely, rufloxacin (RUF), ciprofloxacin (CIP), enrofloxacin (ENO), gatifloxacin (GAT) and moxifloxacin (MOX), in acidic buffer by capillary electrophoresis (CE)-capacitively coupled contactless conductivity detection (C(4)D) technique is presented. Separation was carried out in a fused-silica capillary (42 cm x 50 microm) using a buffer composed of 10 mM tartaric acid, 14 mM sodium acetate and 15% (v/v) methanol at pH 3.8. The RSDs of the migration times and peak areas were 0.65% and 12.3% (intraday), 1.28% and 8.8% (interday), respectively. CE-C(4)D in combination with liquid-liquid extraction (LLE) as clean-up and preconcentration procedure, allows detection of the FQs in fortified chicken muscle samples with detection limits of 6.8-11.7 ng/g. This method shows potential in rapid determination of FQs in samples with complex matrix.