Comparison Of Three Detection Methods For Melamine In Milk And Dairy Products

Melamine,a widely used chemical,is inherently less toxic,but when added to food,it can cause kidney stones and other problems,especially in infants and young children,and even cause death.Early detection of related food,especially milk and dairy products,is an important step to prevent its harm.Much methods have developed for the detection of melamine,but only classical methods such as high performance liquid chromatography,gas chromatography-mass spectrometry,liquid chromatography-tandem mass spectrometry,enzyme-linked immunosorbent assay,and colloidal gold strip have been adopted by national or industry standards.The application of these methods are of great significance to control the harm of melamine.Therefore,it is necessary to compare and investigate these methods,and discuss their detection performance and application scope.In this study,the performance of colloidal gold test strip method,enzyme-linked immunosorbent assay,and liquid chromatography-tandem mass spectrometry for detecting melamine in milk and dairy products were discussed and compared.The main contents are as follows:The immunocolloid gold test strip method was used to detect melamine in pure milk,prepared milk,pasteurized milk,plain yoghurt,and fruit-containing yoghurt.The detection limit of melamine in pure milk,pasteurized milk,and plain yoghurt is 100 ?g/kg,in prepared milk and fruit-containing yoghurt is 150 ?g/kg,which has good repeatability,stability,and specificity.Compared with the high performance liquid chromatography method,the results of the two methods have a good consistency.The sensitivity,specificity,and precision of the detection of melamine in milk anddairy products by enzyme-linked immunosorbent assay were investigated.The results show that the detection limit of the method for melamine in milk and dairy products is 5 ?g/kg,and the linear range is 10 ?g/kg ? 810 ?g/kg,with good specificity and precision.Solid phase extraction and Qu ECh ERS(Quick,Easy,Cheap,Effective,Rugged,Safe)method were used for sample preparation,liquid chromatography-tandem mass spectrometry was used to detect melamine in dairy products,and the performances such as sensitivity,spike recovery,and precision were investigated.The results show that the Qu ECh ERS-based liquid chromatography-tandem mass spectrometry method has higher sensitivity,up to 1.0?g/kg;and the linear range is 5 ?g/kg ? 1000 ?g/kg,which is better than solid phase extraction based-liquid chromatography tandem mass spectrometry.Combined with the actual sample testing,the detection results of the three methods were visually analyzed.