牛羊奶中环丙氨嗪残留检测的液相色谱-三重四极杆/线性离子阱复合质谱技术研究

The Research of Cyromazine Residues in Milk and Goat Milk by Liquid Chromatography-Quadruple/Linear Ion Trap Mass Spectrometry

关键词:  牛奶  羊奶  环丙氨嗪  残留  液相色谱-三重四极杆/线性离子阱

Key words:  milk  goat milk  cyromazine  residues  LC-Qtrap MS

摘要:

建立了一种可准确定性定量检测牛奶和羊奶中环丙氨嗪残留检测的液相色谱-三重四极杆/线性离子阱（LC-Qtrap）复合质谱技术。牛奶和羊奶样品经3%三氯乙酸水溶液提取，MCX固相萃取柱净化。以20 mM乙酸铵水溶液和乙腈溶液为流动相进行梯度洗脱，在HILIC色谱柱上分离，在电喷雾正离子（ESI+）模式下，用多反应监测联合信息依赖性采集与增强子离子扫描（MRM-IDA-EPI）模式检测，同位素内标法定量。结果表明：环丙氨嗪在0.5～20 ng/mL的浓度范围内均呈现良好的线性关系，相关系数（R2）均大于0.990；在牛奶和羊奶中环丙氨嗪的检测限均为0.2 μg/kg，定量限均为0.5 μg/kg。环丙氨嗪在牛奶和羊奶0.5～5 μg/kg添加浓度水平上的回收率在98.4～106%范围内；批内RSD在0.795~2.45%之间，批间RSD在4.86~5.68％之间。该方法具有简便快速、灵敏度高、定性准确，重复性好等特点，可以满足牛羊奶中环丙氨嗪残留检测的要求。

Abstract:

A liquid chromatography-quadruple/linear ion trap mass spectrometry (LC-Qtrap MS） method with good accuracy was established for the determination of cyromazine residues in milk and goat milk. Cyromazine was extracted with 3% trichloroacetic acid water solution. Then the sample solutions were purified with MCX SPE column. The mobile phase were water (20 mM ammonium acetate) and acetonitrile, and the samples were separated by HILIC column. LC-Q-trap MS analysis was performed by positive ion electrospray ionization (ESI+) applying the detection mode of MRM-IDA-EPI. The method was quantified by isotopic internal standard curves. Good linearities of the calibration curves were obtained with the range of 0.5~20 ng/mL, the correlation coefficient R2＞0.990. The limit of detection of cyromazine was 0.2 μg/kg, and the limit of quantification of cyromazine was 0.5 μg/kg. The recoveries of cyromazine residues were 98.4～106%%, for milk and goat milk at the concentrations of 0.5～5 μg/kg. The intra- batch variation coefficients were 0.795~2.45%, and inter-batch variation coefficients were 4.86~5.68%. With high sensitivity, good accuracy and repeatability, the method can be applied for the determination of cyromazine residues in milk and goat milk.