低共熔溶剂固相萃取-高效液相色谱法同时测定粮谷中7种农药残留

Simultaneous determination of 7 kinds of pesticide residues in cereal grain by deep eutectic solvents solid phase extraction-high performance liquid chromatography

目的建立低共熔溶剂固相萃取-高效液相色谱-紫外可变波长(high performance liquid chromatography-ultraviolet variable wavelength detection, HPLC-UV)测定粮谷中7种农药(吡虫啉、啶虫脒、多菌灵、除虫脲、灭幼脲、辛硫磷、阿维菌素)残留的检测方法。方法 选用中性氧化铝作为分散剂,加入低共熔溶剂(deep eutectic solvents, DESs)对样品进行基质分散固相微萃取,充分研磨萃取后装入固相萃取小柱用6 mL乙腈洗脱,洗脱液吹干,用1 mL流动相定容后待测。采用高效液相色谱仪-紫外可变波长检测模式进行测定,流动相为甲醇+乙腈(7:3, V:V)混合溶液-水,色谱柱为ODS-C_(18)柱(250 mm×4.6 mm, 5μm)。结果 在0.05~5.00 mg/kg范围内7种农药残留均呈良好的线性关系,相关系数r^(2)均大于0.9990,方法检出限范围为0.01~0.05 mg/kg,定量限范围为0.03~0.15mg/kg,平均回收率范围为86.0%~99.1%,相对标准偏差(relative standard deviations,RSDs)范围为1.25%~4.65%。结论 本方法简单快捷、成本低廉,设备易满足,具有良好的准确性、精密度、灵敏度,可用于粮谷中7种农药残留的快速检测。

Objective To establish a method for the determination of 7 kinds of(imidacloprid,acetamiprid,carbendazim,diflubenzuron,chlorobenzuron,phoxim,avermectin) residues in cereal grain by deep eutectic solvents solid phase extraction-high performance liquid chromatography-ultraviolet variable wavelength detection(HPLC-UV).Methods Neutral alumina was used as the dispersant,and deep eutectic solvents(DESs) was added to carry out matrix dispersion solid phase microextraction on the sample,after the samples were fully ground and extracted,they were loaded into a solid-phase extraction column and eluted with 6 mL acetonitrile,the eluate was dried and allowed to volume with 1 mL mobile phase before being tested.The determination was performed using a high performance liquid chromatography with variable wavelength ultraviolet detection mode using a mobile phase consisting of a mixture of methanol and acetonitrile(7:3,V:V) in water on an ODS-Ccolumn(250 mm×4.6 mm,5 μm).Results The linear relationships of the 7 kinds of pesticide residues were good in the range of 0.05-5.00 mg/kg,with correlation coefficients r2>0.9990,the limits of detection were in the range of 0.01-0.05 mg/kg,the limits of quantitation were in the range of 0.03-0.15 mg/kg,the average recoveries were in the range of 86.0%-99.1%,and the relative standard deviations(RSDs) was in the range of 1.25%-4.65%.Conclusion This method is simple,rapid,low-cost,easy to meet the requirements of equipment,with good accuracy,precision and sensitivity,and can be used for rapid detection of 7 kinds of pesticide residues in cereal grain.