气相色谱-质谱法测定蔬菜和水果中193种农药的残留量

Determination of 193 pesticide residues in vegetables and fruits by gas chromatography-mass spectrometry

在系统优化固相萃取吸附剂填料类型、洗脱溶剂种类及体积的基础上,建立了蔬菜和水果中193种农药残留的气相色谱-质谱(GC-MS)检测方法。样品经乙腈均质提取,C18/PSA固相萃取柱净化,乙腈洗脱,GC-MS选择离子监测(SIM)模式检测,以磷酸三苯酯内标法定量。结果表明,130种农药在10～1 000μg/L、34种农药在20～1 000μg/L、26种农药在50～1 000μg/L、3种农药在100～1 000μg/L范围内线性关系良好,相关系数为0.996 7～1.000 0,方法检出限(以信噪比为3计)为0.04～8.26μg/kg,添加回收率为71.6%～117.9%,相对标准偏差为3.0%～11.8%。该方法样品处理简单快速,相比其他多残留分析方法净化效果好,其灵敏度和选择性明显提高,适用于日常检测工作。

On the basis of optimization of solid phase extraction adsorbent, eluting solvent types and amounts, a gas chromatography-mass spectrometric method was developed for the determination of 193 pesticide residues in vegetables and fruits. The analytes were extracted from the samples using acetonitrile. The extract was cleaned-up with a CIJPSA solid-phase extractor, eluted by acetonitrile and analyzed by GC-MS under selected ion monitoring （SIM） mode using triphenyl phosphate （TPP） as internal standard. The linear range was from l0 to 1 000 g/L for 130 pesticides, from 20 to l 000 g/L for 34 pesticides, from 50 to 1 000 g/L for 25 pesticides, from 100 to l 000 g/L for the other 3 pesticides with the good correlation coefficients （r〉0. 995 7）. The limits of detection were 0.04 -8.26 g/kg. The mean recoveries of the pesticides were 71.6% -llT. 9%. The relative standard deviations were 3.0% - 11. 8%. This method is simple, rapid, sensitive and specific. It is appropriate for the simultaneous identification and quantification of the multi-residues in fruits and vegetables.