固相萃取-气相色谱-质谱联用测定水体中拟除虫菊酯残留

DETERMINATION OF PYRETHROID PESTICIDE RESIDUES IN WATER BY GAS CHROMATOGRAPHY—MASS SPECTROMETRY WITH SOLID PHASE EXTRACTION.

建立了水中多种拟除虫菊酯类农药残留的固相萃取-气相色谱-质谱(GC/MS)联用检测方法。水样用C18固相萃取碟富集吸附水样中待测组分,以石油醚+乙酸乙酯(95 +5 )洗脱;DB - 5MS毛细管柱分离,全扫描scan定性确认,选择离子监测SIM模式进行定量 结果表明,该方法能同时分离测定水体中6种拟除虫菊酯类农药。6种农残组分的基体加标平均回收率为79 37%～10 3 4 % ,方法的相对标准偏差为5 6 6 %～13 2 % ,水样浓缩2 5 0 0倍的最低检测限为0 0 0 16～0 0 0 5 5 μg/L 该方法与《生活饮用水卫生规范》2 0 0 1年版执行的国标法相比,有机溶剂用量少,样品萃取容量大,极大地提高了方法的灵敏度和准确性。

A Gas Chromatography-Mass Spectrometry method for the determination of pyrethroids in water using solid phase extraction has been established. Wate sample was extracted with 5% ethyl acetate-petroleum ether, and then separated by GC with an DB-5MS capillary column. Pyrethroid qualitative component were achieved by scan mode and quantitation by SIM mode. The results showed that six analytes of pyrethroid were simultaneously identified and quantified. The average recoveries of six pyrethroids ranged from 79.37% to 103.4% and their relative standard deviation varied between 5.66% and 13.2%. Detection limit of each component diluted 2500 times were 0.0016～0.0055 μg/L. Compared with Sanitary Standard for Drinking Water in 2001 annually, the method enormously enhances analytical sensitivity and accuracy, which is satisfied with Allowance Limits of pyrethroids for water in China and European with less usage of organic solvent and great content of extraction.