Study on Analytical Method of Cyromazine and Melamine Residues in Egg,Milk and Pork with HPLC

A high-performance liquid chromatography(HPLC) with NH2 column and 97% acetonitrile-water as mobile phase to determine the cyromazine and melamine residues in egg,milk and pork was described in this paper. Samples were treated with NaOH,extracted with acetonitrile containing 20% NH4OH,and cleaned up by using C18 column solid-phase extraction(SPE). A perfect separation for cyromazine and melamine was achieved with their respective retention time 8 and 12 min. The calibration curves for cyromazine and melamine are linear in the concentration range of 0.01 to 1.0 μg/ml,with the correlation coefficients of 0.9999 and 0.9994,respectively. The detection limits of both the compounds is 0.02 mg/kg and the quantification limit is less than 0.05 mg/kg.