QuEChERS-气相色谱-质谱法测定3种食品中11种农药残留

Determination of 11 pesticide residues in three foods by QuEChERS method coupled with gas chromatography-mass spectrometry

目的 建立气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)结合基质匹配标准系列测定3种食品中11种农药残留的分析方法 .方法样品采用QuEChERS(Quick,Easy,Cheap,Effective,Rugged,Safty)方法,用乙腈溶液进行提取,经N-丙基乙二胺(primary secondary amine,PSA)、十八烷基硅烷键合硅胶(C18)和无水硫酸镁固相分散净化,浓缩定容后用GC-MS在选择离子监测模式(select ion monitoring,SIM)下进行测定,外标法定量.结果 净化剂含量为200 mg PSA、2 g无水MgSO4时,11种农药残留均有较好的回收率,最终确立了采用优化后的QuEChERS(Quick,Easy,Cheap,Effective,Rugged,Safty)方法进行前处理,GC/MS检测样品的分析方法.该方法在3种基质、3个添加水平下的回收率在72.1%~112.4%之间,相对标准偏差均小于7.0%.结论 该方法操作简便、灵敏度高,能够满足日常检验工作的要求.

Objective To establish a method for simultaneous determination of 11 kinds of pesticide residues in 3 kinds of foods by QuEChERS pretreatment and gas chromatography-mass spectrometry(GC-MS) combined matrix matching standard series. Methods The samples were extracted with acetonitrile solution by QuEChERS(quick, easy, cheap, effective, rugged, safety) method, purified by n-propylethylenediamine(PSA), octadecylsilane bonded silica gel(C18) and anhydrous magnesium sulfate solid-phase dispersion, and determined by GC-MS under the selected ion monitoring mode(SIM) after concentration and constant volume, and quantified by external standard method. Results 200 mg of PSA, 2 g anhydrous MgSO4, 11 kinds of pesticide residues were good recovery. Finally, the optimized QuEChERS(Quick, Easy, being inexpensive, Effective, Rugged, Safty) method for pretreatment, GC/MS method for samples analysis was established. The recovery rate of the method was 72.1%-112.4% under three substrates and three addition levels, and the relative standard deviation was less than 7.0%. Conclusion This method is easy to operate, sensitive and can meet the requirements of daily inspection.