Determination of melamine residue in foods by ultra performance liquid chromatography-electrospray tandem mass spectrometry

Objective:To develop a UPLC-MS/MS method for the determination of melamine residue in foods.Methods:The melamine in samples was extracted with 1% acetocaustin and cleaned up with MCX SPE cartridge,the analyte was determined by UPLC-MS/MS,multi-reaction monitoring(MRM) mode was employed for the quantitative determination,and quantified by the external standard curve.The separation was performed on a UPLC BEH HILIC column with a system of water(containing 10mmol/L ammonium acetate buffer)-acetonitrile as mobile phase at a flow rate of 0.3 ml/min.Results:The limit of determination of this method was 50 μg/kg.The detection limits of 50~500 μg/kg proved to be much better than the previously reported ones.Average recoveries of melamine ranged from 76.6% to 103.9%,with relative standard deviations between 6.6% and 10.6%.Conclusion:The method is simple,accurate and suitable for the identification and quantification of melamine residue in foods.