A simultaneous analytical method for testing the cyromazine and melamine residues in chicken excretion by HPLC

This paper is aimed to report a simultaneous analytical method for testing the cyromazine and melamine residues in chicken excretion by using HPLC.The sample for analysis has been extracted from the trichloroacetic acid solution for 30 min and ultrasonic shake for 10 min at a ratio of 1 % , and then was centrifuged.The solid residue under the centrifuged tube was extracted for more than one time.The extracted liquid, the sum total of the two limes was cleaned up and concentrated by HyperSep Retain-CX column solid-phase extraction (SPE).Elution materials were chosen purified with methanol and determined finally by using the high-performance liquid chromatography.Cyromazine and melamine adopted have been separated on a Hypersil NH2 column (Hypersil NH2, 5 μm ,4.6 mm× 250 mm) with 97% acetronitrile solution (97:3, by volume) as the mobile phase at a flow rate of 1.0 mL/m in and the detection wavelength of 214 nm.In so doing, we have made a perfect separation for cyromazine and melamine and decided the retention time respectively at about 10-11 min and 18-19 min at 214 nm.The standard curve was made linear in a concentration range of 0.1-5.0 μg/mL, with the correlation coefficient of 0.999 9 for the cyromazine and 0.999 5 for the melamine.In addition, we have found the recoveries of cyromazine and melamine at the fortified levels of 0.5 mg/kg, 1.0 mg/kg and 5.0 mg/kg, which ranges from 77.52%-87.56% and 68.95%-87.60% respectively with the relative standard deviation (RSD) of 5.54%-10.29%.The limit of detection was 0.1 μg/g for cyromazine and 0.1 μg/g for melamine.Thus, it can be concluded that what we have worked out is a HPLC method for determining cyromazine and melamine in chicken excretion, which can meet the requirements of the veterinary drug and contaminations analysis.