Separation and determination of nitrofuran antibiotics in turbot fish by microemulsion electrokinetic chromatography

A microemulsion electrokinetic chromatography (MEEKC) method has been developed for the determination of four nitrofuran antibiotics (furazolidone (FZD), furaltadone (FTD), nitrofurazone (NFZ) and nitrofurantoin (NFT)) in turbot fish. The effect of buffer the pH, the concentration of SDS and the concentrations of octane and butan-1-ol were studied systematically. With the optimized experimental conditions (octane, 0.82% (w/w); SDS, 3.48% (w/w); butan-1-ol, 6.48% (w/w); and 10 mM sodium tetraborate buffer (pH 9.70), with 30 kV as the applied voltage) all four analytes were baseline-separated within 8 min. Regression equations revealed a good linear relationship between the peak area of each compound and its concentration. The correlation coefficients of the four analytes were from 0.9945 to 0.9999. The relative standard deviations of the migration times and the peak areas were <1.84 and 5.16% (intra-day). The obtained recovery ranged between 97 and 104%. Moreover, the method was successfully validated and applied to the determination of nitrofuran antibiotics in contaminated fish.