Micellar LC Determination of Melamine in Dairy Products

Melamine in dairy products was determined by micellar liquid chromatography. The influence of kinds of surfactants and their concentrations,kinds of denaturants and the amounts required,column temperature and pH value of the mobile phase on the retention time of melamine was studied. As shown by the experimental results the capacity factor (k′) of melamine decreased obviously with the increase of organic modifier,concentration of SDS and pH value of the mobile phase. The high separation efficiency of melamine from other components was attained under the selected chromatographic conditions. The linearity range was found in the range 0.1-100 mg·L-1 of melamine. The limit of detection (3S/N) and lower limit of determination (10S/N) for melamine was found to be 0.02 and 0.07 mg·kg-1 respectively. Precision was tested with a same sample for 9 determination,value of RSD found was 1.28%. Recovery was tested by standard addition method,giving results in the range of 97.64%-99.91%.