Liquid-chromatographic determination of sulfadimidine in milk and eggs

A method for the determination/identification of residual sulfadimidine (SDD) in milk and eggs by highperformance liquid chromatography (HPLC) with a photodiode array detector was developed. The sample preparation was performed by shaking with a mixture of 20% (w/v) trichloroacetic acid-methanol (4:1,v/v) followed by ultra-filtration using Molcut II(R). A LiChrospher(R) 100 RP-S (e) column and a mobile phase of 4% (v/v) acetic acid solution-acetonitrile (6:4, v/v) were used. The average recoveries from spiked SDD samples were 80.8-88.0% with coefficients of variation of 2.8-5.5%. The limits of detection in milk and eggs were 0.01 mu g/mL and 0.01 mu g/g, respectively. The total time required for the analysis of one sample was less than 20 min.