Analysis of danofloxacin, difloxacin, ciprofloxacin and sarafloxacin in honey using micellar liquid chromatography and validation according to the 2002/657/EC decision

Abstract

A reliable and sensitive method based on micellar liquid chromatography was optimized for the analysis of the fluoroquinolones danofloxacin, difloxacin, ciprofloxacin and sarafloxacin in honey. The sample was 1 : 1 diluted in a 0.05 M sodium dodecyl sulfate solution buffered at pH = 3, thus avoiding an extraction step and the use of toxic chemicals. The fluoroquinolones were resolved in less than 25 min using a C18 column, without interference from the matrix. The mobile phase was a solution of 0.05 M sodium dodecyl sulfate, 1% 1-butanol and 0.5% triethylamine buffered at pH = 3, running under isocratic mode at 1 mL min⁻¹. The excitation and emission wavelengths were 280 and 455 nm, respectively. The method was validated in accordance with the European Union Decision 2002/657/EC in terms of selectivity, sensitivity (limits of detection and quantification, 4 and 10 μg kg⁻¹, respectively), calibration range (10–200 μg kg⁻¹), linearity (r² > 0.9990), decision limit (4 μg kg⁻¹), detection capability (4.7–6.2 μg kg⁻¹), intra- and interday accuracy and precision (81.0–103.4% and <12.3%, respectively), and robustness (<8.5%). The method was applied to commercial honey samples purchased from a local supermarket.