超高效液相色谱检测奶及奶制品中的M族黄曲霉毒素

Determination of M aflatoxins in milk and milk products by ultra high performance liquid chromatography

目的：建立一种免疫亲和柱净化-超高效液相色谱法同时测定奶及奶制品中M族黄曲霉毒素的方法。方法以乙腈为提取剂和蛋白沉淀剂,采用涡旋混合及超声提取,免疫亲和柱净化。结果经 Welch Ultimate XB-C18色谱柱(100 mm×2.1 mm,1.8μm)分离,应用大体积流通池荧光检测,流动相为水和乙腈/甲醇(1：1)。线性范围在0.01~5.00 ng/mL之间,线性系数均大于0.999,黄曲霉毒素M1、M2的检出限为0.003μg/kg。免疫亲和柱对黄曲霉毒素M1、M2的回收率均在80%以上,液态奶中添加0.05、0.2、1.0μg/kg的回收率在85.6%~106.4%之间,奶粉中添加0.5、2.0、10.0μg/kg的回收率在81.5%~93.4%之间。结论该方法可以适用于奶粉、液态奶中M族黄曲霉毒素检测。

Objectives To develop the method of simultaneous determination of M aflatoxins in milk and milk products by ultra high performance liquid chromatography (UPLC) coupled with immunoaffinity column (IAC) clean-up. Methods Samples were extracted with acetonitrile after vortex mixing and ul-trasound, meanwhile, acetonitrile was used as an protein precipitant, then extraction solution was clean-up with IAC. Results The analytes were separated on Welch Ultimate XB-C18 (100 mm×2.1 mm, 1.8 μm), and eluted with a mobile phase consisting of (a) waters and (b) acetonitrile: methanol (50: 50, v/v). The separated compounds were detected with fluorescence detection (FLD) equipped with a large volume flow cell. Meanwhile, high correlation coefficient (R2>0.999) was obtained within linear range from 0.01 to 5.0 ng/mL, and the limits of determination (LOD) of M aflatoxins were 0.003 μg/kg. Reasonable recove-ries (above 80%) were demonstrated for aflatoxin M1 and M2 with aflatoxin M1 immunoaffinity column, and recoveries (85.6%~106.4%) were in 3 spiked levels (0.05, 0.2, 1.0 μg/kg) for milk, and recoveries (81.5%~93.4%) were in 3 spiked levels (0.5, 2. 0, 10.0 μg/kg) for milk powder. Conclusion This quan-titative method can be applied to the determination and quantification of M aflatoxins in milk and milk products.