Determination of Melamine in Milk and Milk Products by High Performance Liquid Chromatography

Objective To develop a analytical method for melamine in milk and milk products.Method The melamine was extracted with 0.1 mol/L HCl,and the protein were precipitated by sulfosalicylic acid(60 g/L).The samples were determined by high performance liquid chromatography with a column of Kromasil KR100-5C8 at the wavelength of 200-400 nm.The mobile phase were buffer-acetonitrile(85+15,V/V).The buffer was the mixed solution of 10 mmol/L citric acid and 10 mmol/L sodium octanesulfonate.Results The fortified recoveries of melamine in milk and milk products were from 80% to 105%.The relative standard deviation was less than 10%,and the limit of quantification(LOQ) was 1.0 mg/kg.Conclusion The method could be fast,accurate,simple,convenient,and could meet the needs of determination of Melamine in milk and milk products.