GC-MS/MS法检测水果中双甲脒及其水解产物的2,4-二甲基苯胺残留量

Determination of 2,4-Dimethylaniline Residue in Fruit by GC-MS/MS

目的:建立一种气相色谱串联质谱法检测水果中双甲脒及其水解产物2,4-二甲基苯胺残留量的分析方法。方法:使用酸水解法将样品中双甲脒水解为2,4-二甲基苯胺,再在碱性环境下使用正己烷萃取,不分流进样,外标法定量。结果:双甲脒及其水解产物2,4-二甲基苯胺在0.02~0.50μg·mL^(-1)线性关系良好,相关系数(R^(2))均大于0.990,双甲脒的定量限为15.0 ng·mL^(-1),2,4-二甲基苯胺的定量限为7.5 ng·mL^(-1)。结论:该方法前处理操作简单,成本低廉,试剂毒性小,可以满足大多数实验室检测水果中双甲脒及其水解产物2,4-二甲基苯胺残留量的需求。

Objective:To establish a gas chromatography-tandem mass spectrometry method for the determination of dimethylamidine and its hydrolysate 2,4-dimethylaniline residues in fruit.Method:Dimethylamidine was hydrolyzed to 2,4-dimethylaniline by acid hydrolysis,and then n-hexane extraction was used in alkaline environment.Result:The linear relationship between diformamidine and its hydrolysate 2,4-dimethylaniline was good in the range of 0.02 to 0.50μg·mL^(-1),and the correlation coefficients(R^(2))were all greater than 0.990.The limit of quantification of diformamidine was 15.0 ng·mL^(-1),2,4-dimethylaniline was 7.5 ng·mL^(-1).Conclusion:The pretreatment method is simple,low cost and less toxic,which can meet the requirements of most laboratories for the determination of diformamidine and its hydrolysate 2,4-dimethylaniline residues in fruits.