Simultaneous determination of fluoroquinolones in feed by liquid chromatography with fluorescence detection

An H PLC method with fluorescence detection (HPLC-FLD) was developed for the simultaneous quantitative determination of enrofloxacin, ciprofloksacin, sarafloxacin, and difloxacin in feed. The samples were extracted with 0.25% formic acid in ultrasonic bath and purified by solid phase extraction (SPE) on Strata-X cartridges. The samples were analysed on Luna C8 liquid chromatography column with gradient programme by acetonitrile and 0.025 M phosphoric acid with 0.0025 M sodium 1- heptanesulfonate monohydrate. The method was successfully validated according to the requirements of the European Decision 2002/657/EC. Recoveries of the components from spiked feed samples ranged from 55%- 70%. Repeatability was <7%. The method presented here proved to be efficient, rapid, and a selective approach for determination of fluoroquinolones in feed.