一种利用QuEChERS-GC/MS测定苹果种植土壤中5种常见菊酯类农药的方法研究

QuEChERS-GC/MS method for determination of 5 pyrethroid pesticide residues in planting soil of apple

实验建立利用QuEChERS提取苹果种植土壤中的5种菊酯类农药(甲氰菊酯、联苯菊酯、高效氯氟氰菊酯、氯菊酯、氰戊菊酯),气相色谱-质谱法定性定量检测的分析方法。苹果种植土壤样品用乙腈:冰乙酸(9:1,V/V)进行超声提取,QuEChERS方法进行净化处理,净化后的溶液用氮吹仪吹干,残渣用丙酮溶解定容至1 mL,0.45μm滤膜过滤,GC-MS仪定性定量检测。结果表明:5种菊酯类农药在0.1～50.0μg/mL范围内线性关系良好,r2均大于0.995;检出限在0.008～0.02 mg/kg之间,加标回收率范围为80.6%～106.7%;精密度相对标准偏差在1.8%～2.8%之间,重复性相对标准偏差在3.5%～4.6%之间。实验证明该方法具有前处理简单、检测速度快、灵敏度高、检测结果准确等优点。

A QuEChERS pr-treatment method for extracting 5 pyrethroid pesticide residues(fenpropathrin,bifenthrin,lambda-cyhalothrin,permethrin and fenvalerate)in planting soil of apple and GC/MS method for determination quantitatively was established.Planting soil of apple samples were ultrasoned and extracted by acetonitrile:glacial acetic acid(9:1,V/V),QuEChERS was used for sample purifying.Purification solution was firstly concentrated to dry under nitrogen,then the residue was dilute with acetone to 1 mL,filtered with 0.45μm filter membrane and detected qualitatively and quantitatively by GC/MS.It was showed that concentration of 5 pyrethroid pesticide showed good linear relationships in the range 0.1-50.0μg/mL,the correlation coefficients were all above 0.995.The detection limits were bewteen 0.008-0.02 mg/kg and the recoveries were ranged from 80.6%-106.7%.RSD of precision were ranged from 1.8%-2.8%,Repeatability of the relative standard deviation(RSD)of 6 pesticide residues were 3.5%-4.6%.This method was proved to be simple and quick pre-treated with high sensitivity and accuracy.