GC-MS测定番茄及土壤中二甲基二硫醚残留含量的分析方法

Analytical Method for Determination of Dimethyl Disulfide Residues in Tomato and Soil by GC-MS

[目的]建立GC-MS测定二甲基二硫醚在番茄果实及土壤中的残留量分析方法。[方法]样品经甲醇提取,用正己烷液液分配净化后采用气相色谱-质谱联用仪(GC-MS)进行测定。[结果]二甲基二硫醚标准曲线的线性范围为0.002~1mg/L,相关系数为0.9999。二甲基二硫醚在番茄中的平均回收率为76.4%~82.1%相对标准偏差为3.1%~8.9%;在土壤中的平均回收率为71.5%~84.0%,相对标准偏差为1.5%~5.7%。方法的检出限(LOD)为1.5×10^(-3)ng,定量限(LOQ)为5.0×10^(-3)ng,符合农药残留分析要求。[结论]建立了一个简便、快捷、准确的二甲基二硫醚农药残留分析方法。

[Aims] An analytical method for determination of dimethyl disulfide （DMDS） residues in tomato and soil by gas chromatography-mass spectrometry （GC-MS） was established. [Methods] The samples were extracted with methanol, cleaned up with n-hexane, and analyzed by GC-MS. [Results] The results showed that the linear range of calibration curve was 0.002-1 mg/L, and the linear correlation coefficient was 0.9999. The average recoveries of DMDS were 76.4-82.1% in tomato and 71.5-84.0% in soil, the RSDs were 3.1-8.9% in tomato and 1.5-6.7% in soil. The limit of quantitation （LOD） of the method was 1.5 × 10^-3 ng, and the limit of determination （LOQ） was 5.0 ×10^-3 ng, which conforms to requirements of pesticide residue analysis. [Conclusions] A simple, fast and sensitive method was developed for determination of DMDS residues in tomato and soil.