固相支持液-液萃取GC-PFPD法测定武昌鱼中的毒死蜱残留

Determination of chlorpyrifos residues in Wuchang fish by GC-PFPD with solid phase extraction and liquid-liquid extraction

目的将液-液萃取与固相萃取相结合,建立武昌鱼中毒死蜱残留的检测方法,能快速、准确检测毒死蜱残留。方法样品经过丙酮-水-石油醚萃取后,将有机相过无水硫酸钠转移到蒸发瓶中,旋蒸近干,加淋洗液溶解后过CARB/NH2柱进行净化,然后用GC-PFPD检测,外标法定量。结果根据GC-PFPD检测武昌鱼中毒死蜱残留的实验条件,当毒死蜱浓度为0.013 mg/kg^30.00 mg/kg时,A=138848ρ+126.3(r=0.9991),检出限为0.008 mg/kg,回收率为90.30%~103.80%。结论该方法填补了单独使用液-液萃取或固相萃取的不足,经过两种前处理方法的结合,并使用先进的火焰脉冲检测器,使该方法灵敏度和回收率高、检出限低、重现性好,适用于鱼中毒死蜱检测工作的需要,值得推广使用。

Objective To establish an accurate and quick method for chlorpyrifos residue detection in Wuchang fish based on combination of liquid-liquid extraction and solid phase extraction. Methods Sample was extracted with acetone-water-petroleum ether. Then the organic phase was transferred over anhydrous sodium sulfate to an evaporating flask for drying,dissolved in elution solution and cleaned up with CARB / NH2column,and finally determined by GC-PFPD,using external standard method for quantification. Results Under the experimental conditions of GC-PFPD for detection of chlorpyrifos residue in Wuchang fish,when the concentration of chlorpyrifos was 0. 013 mg / kg ~ 30. 00 mg / kg,A = 138848ρ ＋ 126. 3（ r = 0. 9991）, the detection limit was 0. 008 mg / kg,and the recovery was 90. 30% ~ 103. 80%. Conclusion Combination of solid phase extraction and liquid-liquid extraction can make up the defficiency of single use of ethier of them. Advanced pulse flame detector,combined with solid phase extraction and liquid-liquid extraction,had merits of the high sensitivity and recovery rate,low detection limit and good reproducibility,it is suitable for chlorpyrifos residue detection in fish and worth promoting.