高效液相色谱-串联质谱法测定奶粉中的双氰胺与三聚氰胺

Determination of dicyandiamide and melamine in powder milk by high performance liquid chromatography tandem mass spectrometry

建立了同时测定奶粉中双氰胺与三聚氰胺含量的高效液相色谱-串联质谱法。采用CAPCELLPAKCR1：4色谱柱（2．0inlni．d×150mm，5IJ．na），V（乙腈）：y（CH3COONH4溶液，2mmol／L，用乙酸调pH=4）=95：5为流动相，流速0．3mL／min，柱温35℃，质谱检测器进行检测，外标法定量。在上述条件下，两种目标化合物在10～500ng／mL范围内，质量浓度与定量离子峰面积呈良好的线性关系。对奶粉样品进行添加回收，双氰胺与三聚氰胺的平均回收率分别为93．4％-97．0％，92．7％～98．1％，相对标准偏差（RsD）分别为3．7％～5．8％，3．4％～5．7％。该方法可用于奶粉样品中双氰胺与三聚氰胺含量的分析。

A method for the determination of dicyandiamide and melamine in powder milk by high performance liquid chromatography-tandem mass spectrometry was developed. The samples were separated on a. CAPCELL PAK CR 1：4 column（2.0 mm i. d×150 mm,5 μm）with 95% acetonitrile ＋5% 2 mmol ammonium acetate（pH =4） as THE mobile phase at a flow rate of 0. 3 mL/min, and detected by mass spectrometry. The target compounds were successfully separated from relevant impurities under the conditions mentioned above. The calibration curve was linear in the range of 10 -500 ng/mL. The average recoveries of dicyandiamide and melamine were 93.4% -97.0% and 92.7 % - 98.1% , and the relative standard deviations （RSD） were 3.7 % - 5.8% and 3.4% - 5.7%, respectively. The method is simple, rapid and suitable for the determination of dicyandiamide and melamine in powder milk.