提出了超高效液相色谱-串联质谱法测定牛奶中黄曲霉毒素M1含量的方法。样品经免疫亲和柱净化,用乙腈洗脱下来。以ACQUITY UPLC BEH C18柱(2.1 mm×50 mm,1.7 μm)为分离柱,乙腈和水为流动相梯度淋洗,用串联质谱测定。采用电喷雾电离正离子模式进行多反应监测。黄曲霉毒素M1的质量浓度在0.1~16.0 μg·L-1范围内与其峰面积呈线性关系,检出限(3S/N)为0.001 5 μg·kg-1,测定下限(10S/N)为0.005 μg·kg-1。方法用于分析牛奶样品,测得回收率在89.5%~101.5%之间,测定值的相对标准偏差(n=6)在2.8%~9.5%之间。

UHPLC was applied to the determination of aflatoxin M1 in milk. Sample was purified by immune affinity column and eluted from the column with acetonitrile. The eluate was separated on ACQUITY UPLC BEH C18 column (2.1 mm×50 mm, 1.7 μm) by gradient elution with mixtures of acetonitrile and water in different ratios as mobile phase, and determined by MS/MS. The positive electrospray ionization as well as multiple reactions monitoring mode was used in the detection. Linear relationship between values of peak area and mass concentration of aflatoxin M1 was obtained in the range of 0.1-16.0 μg·L-1. Values of limit of detection (3S/N) and lower limit of determination (10S/N) found were 0.001 5 μg·kg-1 and 0.005 μg·kg-1 respectively. The proposed method was used in the analysis of milk for its content of aflatoxin M1, giving values of recovery in the range of 89.5%-101.5% with RSD′s (n=6) in the range of 2.8%-9.5%.