优化气相色谱法检测牛奶中双甲脒残留标志物

Optimation the method for determination of amitraz residues in milk by gas chromatography

目的改进国标中的气相色谱法测定牛乳中双甲脒残留标志物残留的前处理与色谱条件。方法样品使用1 mol/L的盐酸溶液提取,10000 r/min离心转速离心5 min,取上清液使用固相萃取(solid-phase extraction,SPE)小柱过滤净化。对气相色谱的色谱条件进行优化,使用外标法定量。结果通过使用优化处理条件,该方法的线性范围在10~400 ng/m L,线性关系良好。添加5、10、25?g/kg浓度水平,回收率均在90.5%~100.2%之间,相对标准偏差为1.4%~3.2%。结论改进后的方法回收率高、准确性高,对牛乳中双甲脒残留物的检测具有重要意义。

Objective To optimize the pretreatment and chromatographic conditions for determination of the residues of amitraz in milk by gas chromatography. Methods Samples were extracted with 1 mol/L of hydrochloric acid solution and centrifuged for 5 min under centrifugal speed of 10000 r/min. The supernatant was filtered by solid-phase extraction（SPE） column. The chromatographic conditions of gas chromatography were optimized and the external standard method was used for quantitative analysis. Results By using the optimal processing conditions, the linear relationship was good in range of 10~400 ng/m L. At the 3 spiked levels of 5, 10, 25 ？g/kg, the recoveries were 90.5%~100.2% and the relative standard deviation were 1.4%~3.2%. Conclusion The improved methods has high recovery rate and high accuracy, which is of great significance for the detection of amitraz residues in milk.