Development of a high-performance liquid chromatography method for the determination of florfenicol in animal feedstuffs

An effective thin layer chromatography (TLC) purification procedure coupled to high-performance liquid chromatography (HPLC) method was developed for the determination of florfenicol (FF) in pig, chicken and fish feedstuffs. The feedstuff samples were extracted with ethyl acetate, defatted with n-hexane saturated with acetonitrile, and further purified by TLC. The chromatographic separation was performed on a Waters Symmetry C18 column using an isocratic procedure with acetonitrile-water (35:65, v/v) at 0.6 mL/min. The ultraviolet (UV) detector was set at a wavelength of 225 nm. The FF concentrations in feedstuff samples were quantified using a standard curve. Good linear correlations (y = 159075 x − 15054, r > 0.9999) were achieved within the concentration range of 0.05-200 μg/mL. The recoveries of FF spiked at levels of 1, 100 and 1000 μg/g ranged from 80.6% to 105.3% with the intra-day and inter-day relative standard deviation (RSD) less than 9.3%. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.02 and 0.06 mg/kg for pig feedstuffs, 0.02 and 0.07 mg/kg for chicken feedstuffs, and 0.02 and 0.05 mg/kg for fish feedstuffs, respectively. This reliable, simple and cost-effective method could be applied to the routine monitoring of FF in animal feedstuffs.