固相萃取-气相色谱法测定猪肉中敌敌畏残留

Determination of dichlorvos in pork by solid phase extraction-gas chromatography

中文关键词:  固相萃取-气相色谱法  猪肉样品  敌敌畏

英文关键词:solid phase extraction-gas chromatography  poke  dichlorvos

中文摘要:

      目的 建立固相萃取-气相色谱法(gas chromatography, GC)测定猪肉中敌敌畏残留量的方法。方法 猪肉样品中残留敌敌畏经过丙酮和二氯甲烷(4:3, V:V)提取后, 经过水浴30 ℃旋转蒸发浓缩。浓缩液由丙酮和二氯甲烷(1:1, V:V)复溶后再由石墨化碳黑/氨基Carbon/NH2(500 mg/500 mg/6 mL)双层固相萃取小柱进行净化处理, 收集净化液再次经过30 ℃旋转蒸发浓缩, 最后浓缩液经由岛津弱极性毛细管柱SH-RTX-5分离, 通过磷滤光片的火焰光度检测器检测, 采用外标法定量。结果 敌敌畏在11 min内完全出峰, 在0.2~1 μg/mL范围内线性关系良好, 相关系数r2为0.9997, 在20、50、100 μg/kg加标水平下, 回收率为100%~120%, 相对标准偏差(relative standard deviation, RSD)为2.60%。结论 该方法准确、灵敏、快速, 具有稳定性强、重现性好等优点, 并且能有效消除基质效应, 适合猪肉样品中的敌敌畏残留量的测定。

英文摘要:

      Objective To establish a method for determination of dichlorvos in pork by solid phase extraction-gas chromatography (GC). Method Dichlorvos residues in pork were extracted by acetone and dichloromethane (4:3, V:V) and then concentrated by rotary evaporation with 30 ℃ water bath. The concentrated solution was reconstituted with acetone and dichloromethane (1:1, V:V) and then purified by graphitized carbon black/amino (500 mg/500 mg/6 mL) double-layer solid-phase extraction cartridge. The purified solution was reconcentrated by rotary evaporation at 30 ℃. The concentrated solution was separated by shimadzu SH-RTX-5 weak polar capillary column, detected by a flame photometric detector of a phosphorus filter, and quantified by external standard method. Result The dichlorvos could be detected within 11 min and had good linearity in the range of 0.2-1 μg/mL, and the correlation coefficient r2 was 0.9997. The recoveries were 100%-120% with 3 spiked levels of 20, 50, and 100 μg/kg. The relative standard deviation (RSD) was 2.60% (n=6). Conclusion This method is accurate, sensitive, rapid, stable, reproducible, and can effectively eliminate the matrix effect, which is suitable for the determination of dichlorvos residues in pork samples.