超高效液相色谱质谱联用测定饲料、牛乳及乳制品中双氰胺

Determination of Dicyandiamide in Feed, Milk and Dairy Products by UPLC-MS-MS

建立超高效液相色谱质谱联用法检测饲料、牛乳及乳制品中双氰胺的方法。研宄适用于检测饲料、牛乳及乳制品的前处理方法，并对色谱柱进行了选择。样品经乙腈提取、C18固相萃取填料净化后，低温冷冻离心除掉杂质，含0．1％甲酸的乙腈溶液和含0．1％甲酸的10mmol／L甲酸铵水溶液梯度洗脱，通过Acquity BEH Amide色谱柱分离，电喷雾正离子多反应监测模式进行检测。结果表明：该方法在1～1000μg／L范围内线性良好，相关系数r大于0．995，饲料定量限最高40μg／kg。不同添加质量浓度的回收率为80．5％～108．4％，相对标准偏差小于7．0％。该方法具有简单方便、检测周期短，适用于饲料、牛乳及乳制品检测等特点。

An ultra performance liquid chromatography-tandem mass spectrometry （UPLC-MS-MS） method for simultaneous determination of dicyandiamide in feed, milk and dairy products was developed. The extraction methods for feed, milk and dairy products were studied, and this was followed by selection of an appropriate chromatographic column. Samples were extracted with acetonitrile and the extract was then cleaned up on a C18 solid-phase extraction column, frozen and certrifuged to remove protein impurities, and separated on an Acquity BEH Amide column using a mobile phase composed of acetonitrile containing 0.1% formic acid and 10 mmol/L ammonium formate solution by gradient elution. Detection was performed by positive ion electrospray ionization （ESI） in multiple reaction monitoring （MRM） mode. The proposed method had good linearity in the concentration range of 1-1000 μg/L with correlation coefficients more than 0.995. The quantification limit for feed was the highest, 40μg/kg. Recoveries at different spiked concentrations were 80.5%- 108.4%, with RSD less than 7.0%. This method proved to be simple, rapid and suitable for the determination of feed, milk and dairy products.