牛奶及乳粉中黄曲霉毒素M_1的液相色谱-质谱检测比较研究

Comparative study on determination of aflatoxins M_1 in milk and its powder by liquid chromatography-mass spectrometry

目的:建立测定牛奶和乳粉中黄曲霉毒素M_1的液相色谱-质谱检测方法,并与国家标准方法比较。方法:采用ACQUITY UPLC HSS T3色谱柱(50 mm×2.1 mm,1.8μm),以0.1%甲酸水溶液-乙腈为流动相进行梯度洗脱,流速0.3mL·min^(-1);采用电喷雾离子源进行正离子模式监测,多反应监测模式(MRM)定量分析,毛细管电压3.2 k V,离子源温度150℃;结果:在均满足日常检测的情况下,本方法较国家标准方法回收率提高10%以上,检出值准确性提高5%以上。测定结果显示采集的市售牛奶和乳粉中均未检出黄曲霉毒素M_1,牛奶质控样品(3.03±0.70)μg·kg^(-1)测定结果为(3.05±0.08)μg·kg^(-1)(n=5),乳粉阳性样品(1.00±0.25)μg·kg^(-1)测定结果为(1.10±0.02)μg·kg^(-1)(n=5)。结论:牛奶及乳粉中黄曲霉毒素M_1的检测可以通过简单制备后进行测定,为日常检测提供了简便可行的方法。

Objective：To develop a method for the determination of alfatoxin M_1 in milk and its powder,and to compare it with current national standard method.Methods：The samples were separated on a n ACQUITY UPLC HSS T3 column（50 mm×2.1 mm,1.8 μm）with a mobile phase of acetonitrile and water containing 0.1% formic acid in a gradient elution at a flow rate of 0.3mL·min（-1）.Multiple-reaction monitoring（MRM）scanning was employed for quantification with switching electrospray ion source polarity in positive mode.The capillary voltage was set at 3.2 k V,and the ion source temperature was maintained at 150 ℃.Results：Both methods could cope with routine test,while the new developed method had by 10% higher recovery rate than the standard method,and the accuracy of target results was promoted by 5%.Aflatoxin M_1 was not detected in both commercially available milk and milk powder,while the results of the determination of quality controled samples in milk with（3.05±0.08）μg·kg（-1）（n=5）,and in milk powder with（1.10±0.02）μg·kg（-1）（n=5）were（3.03±0.70）μg·kg（-1）and（1.00±0.25）μg·kg（-1）,respectively.Conclusion：Alfatoxin M_1 in milk and its powder could be determined after simple treatment and the method provided a simple and easy way for routine tests.