Determination of Cyromazine and Melamine in Soils by High-performance Liquid Chromatographic Method

An analytic method with HPLC was developed to determine the residues of cyromazine and melamine in soils. Soil samples were extracted thrice with ammonia/methanol (5/95,v/v) by ultrasonic and concentrated, and then analyzed by HPLC. The calibration curves for cyromazine and melamine were linear in concentration range of 0.1-15.0 μg/ml (R2=1.0000 and 0.9998, respectively). In the concentration of 0.5-5 mg/kg, the average recoveries of cyromazine and melamine were 87.2%-101.1% and 75.3%-101.6% with the variation coefficient of 3.3%-8.1% and 1.6%-9.9% respectively. The limit of detection was 0.05 mg/kg and 0.07 mg/kg, respectively.