Determination of Sulfonamide Residues in Milk by On‐Line Microdialysis and HPLC

Abstract

A technique for the simultaneous determination of sulfonamides in milk was studied by using a home‐made microdialysis system on‐line to high‐performance liquid chromatography. Six sulfonamides (sulfadiazine, sulfamerazine, sulfamethazine, sulfamonomethoxine, sulfadimethoxine, and sulfamethoxazole) in milk were isolated by a hollow dialysis fiber prior to chromatographic determination. The results shows 2–5 fold enrichments and the detection limits in sub‐µg L−1 levels. As the milk sample was spiked with the six sulfonamides, in the concentration ranges between 0.005 and 10 mg L−1, recoveries ranging from 97.8% to 100.4% were obtained, and the regression coefficients >0.995. The proposed method provides a simple, fast, and eco‐friendly procedure for isolating and determining sulfonamides in milk samples.