蜂蜜中双甲脒及其代谢产物2,4-二甲基苯胺和氟胺氰菊酯的GC-MS残留检测

Residue determination of Amitraz 2,4-dimethyl aniline and Tau-fluvalinate by GC-MS

目的建立双甲脒及其代谢产物2,4-二甲基苯胺和氟胺氰菊酯在蜂蜜样品中同时在线残留检测的气质联用方法,简化分析步骤。方法用弱碱性氢氧化钠溶液溶解蜂蜜样品,正己烷同时提取3种化合物,提取液经浓缩后,GC-MS选择离子方式同时检测3种物质,并进行方法学论证。结果p H<10的弱碱环境下,双甲脒原体稳定,正己烷对其代谢产物2,4-二甲基苯胺的提取效率增大,氟胺氰菊酯的分解速度足够慢,可以保证残留分析的顺利进行。各化合物的浓度与GC-MS相应定量离子的响应峰面积呈良好的线性关系。以最低加标浓度作为方法检出限,3种化合物的最低检出浓度均为0.01 mg/kg,平均回收率为83.62%~109.75%,RSD最大为14.38%。结论本方法操作简便、灵敏度高、定量准确可靠,各项指标均符合农药残留检测的要求。

Objective To establish a GC-MS method for the simultaneous residual detection of Amitraz,2,4-dimethyl aniline and Tau-fluvalinate in honey samples.Analysis steps of the test had been greatly simplified.Methods The honey sample was dissolved in weak alkaline sodium hydroxide solution.Then three target compounds in solution were extracted with n-hexane.Finally,three target compounds were detected by GC-MS.Results In the weak alkaline environment with p H less than 10,Amitraz had certain stability,the extraction efficiency of n-hexane to 2,4-dimethylaniline increased,and the decomposition rate of Tau-fluvalinate was slow enough to ensure the smooth progress of residue analysis.There was a good linear relationship between the concentration of each compound and the response peak area of corresponding quantitative ion in GC-MS within a certain concentration range.The detection limit of the method was the lowest standard-added concentration.The detection limits of Amitraz,2,4-dimethyl aniline and Tau-fluvalinate were all 0.01 mg/kg.The average recovery ranges of three compounds were from 83.62%to 109.75%,and the maximum RSD was 14.38%.Conclusion The method was simple,sensitive,accurate and reliable in the determination of three pesticides’residues in honey samples.All indicators met the requirements of pesticide residue detection.