超高效液相色谱-串联质谱法测定牛奶中三氮脒残留

Determination of diminazene in milk by ultra performance liquid chromatography-tandem mass spectrometry

中文关键词:  三氮脒  牛奶  超高效液相色谱－串联质谱法

英文关键词:diminazene  milk  ultra performance liquid chromatography-tandem mass spectrometry

中文摘要:

      目的 建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)检测牛奶中痕量三氮脒残留的分析方法。方法 样品采用1%乙酸乙腈溶液振荡提取后, 在–4℃条件下高速离心, 取上清液旋转蒸干, 以10%乙腈水溶液复溶, 用UPLC-MS/MS检测。采用BEH C18色谱柱(100 mm×2.1 mm, 1.7 μm)分离, 以乙腈-0.1%甲酸水溶液作为流动相梯度洗脱, 流速为0.2 mL/min, 在正离子扫描及多反应监测(multiple reaction monitoring, MRM)模式下分析, 外标法定量。结果 牛奶中三氮脒的检出限(limit of detection, LOD)为5 μg/kg, 定量限(limit of quantification, LOQ)为15 μg/kg, 在20~1000 μg/L质量浓度范围内线性良好, 相关系数(r)为0.9993。将所研究的方法应用于实际牛奶样本中, 其日内加标回收率在81.67%~85.49%, 日内精密度在4.5%~5.5%, 日间加标回收率在81.07%~85.12%, 日间精密度在5.9%~8.2%。结论 本方法采用振荡提取加低温高速离心净化的前处理方法, 简单快速, 结合UPLC-MS/MS, 可实现痕量水平残留的高灵敏度检测, 适用于牛奶中的三氮脒残留的快速检测, 为动物源性食品中三氮脒残留的定性与定量分析提供技术参考。

英文摘要:

      Objective To establish a method for the determination of trace diminazene residues in milk by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods Samples were extracted by oscillation with 1% acetic acid-acetonitrile, after high-speed centrifugation at –4℃, the liquid supernatant was dried by rotary evaporation and dissolved with 10% acetonitrile aqueous solution, and determined by UPLC-MS/MS. A BEH C18 column (100 mm×2.1 mm, 1.7 μm) was used for separation, and acetonitrile-0.1% formic acid aqueous solution was used as mobile phase for gradient elution, the elution flow rate was 0.2 mL/min. The positive ion scanning mode and multiple reaction monitoring (MRM) was used, and the external standardization method was used for the quantitative analysis. Results The limit of detection (LOD) and limit of quantification (LOQ) of diminazene in milk were 5 μg/kg and 15 μg/kg, respectively. In the mass concentration range of 20–1000 μg/L, the linearity was good, with a correlation coefficient (r) of 0.9993. The recoveries ranged from 81.67% to 85.49% (intra-day) and 81.07% to 85.12% (inter-day) when applied in milk detection, with intra-day precisions of 4.5%–5.5% and inter-day precisions of 5.9%–8.2%. Conclusion This method adopts a pretreatment method of oscillation extraction and low-temperature high-speed centrifugation purification, which is simple and fast. By incorporating UPLC-MS/MS, high sensitivity detection of trace residues can be attained, making it suitable for the rapid detection of triazamidine residues in milk, providing technical reference for the qualitative and quantitative analysis of diminazene residues in animal derived foods.