采用胶束液相色谱法直接测定乳制品中三聚氰胺.考察了表面活性剂的种类及浓度、有机改性剂种类及用量、柱温、流动相pH值等对三聚氰胺色谱保留时间的影响.结果表明:随着有机改性剂增加、十二烷基硫酸钠(SDS)浓度增大和流动相pH值增大,三聚氰胺的容量因子(k′)明显减小.在所选定的条件下,三聚氰胺与乳制品中其他组分之间具有较好的分离效果.三聚氰胺质量浓度在0.1~100 mg·L-1范围内呈线性关系,检出限(3S/N)和测定下限(10S/N)分别达0.02,0.07 mg·kg-1.对同一试样的9次平行测定结果的相对标准偏差为1.28%,平均加入回收率为97.64%~99.91%.

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%.