摘要
目的建立固相萃取-气相色谱法测定水果中14种有机氯及拟除虫菊酯类农药残留的检测方法。方法样品用乙腈提取,提取液经无水硫酸钠脱水、氮气吹至近干,用2mL甲醇-二氯甲烷(1+99)溶液溶解,经NH_2基固相萃取柱净化后,淋洗液用氮气吹至近干,用丙酮溶解并定容至1mL。采用HP-5毛细管柱(30m×0.32mm×0.25μm)进行分离,μECD检测器检测,气相色谱法测定,外标法定量。结果在20~200μg/L范围内,14种农药的线性关系良好(r≥0.9977),方法检出限为0.00030mg/kg^0.00400mg/kg,三个添加浓度的平均加标回收率为70.4%~120.0%,相对标准偏差(n=6)为1.7%~15.0%。结论本方法灵敏度高,精密度和准确度好,适合于水果中14种有机氯及拟除虫菊酯类农药残留的测定。
Objective To establish a method for the determination of 14 organochlorine and pyrethroid pesticide residuesin fruits by using solid phase extraction coupled with gas chromatography（GC）. Methods The samples were extracted withacetonitrile, the extract liquor was dehydrated with anhydrous sodium sulfate and dried-up under nitrogen gas,redissolved inmethanol- dichloromethane solution and constanted volume to 2 mL. Then the obtained supernatant was cleaned up by NH_2 SPE, the eluent dried-up under nitrogen gas,and redissolved in acetone and constanted volume to 1 mL, and further separated on a HP-5 capillary column（30 m×0.32 mm×0.25 μm）. GC-μECD（electron capture detector） was used to collect signals. The target substances were determined by GC, and their quantification was determined by external standard method. Results Within the scope of 20-200 μg/L, a good linear result was attained for the 14 organochlorine and pyrethroid pesticide residuesin the range of determination（r ≥0.997 7）. The detection limit were 0.000 30-0.004 00 mg/kg. The average recovery rates of 3spiked levels ranged from 70.4% to 120.0%, with the relative standard deviations of 1.7%-15.0%（n =6）. Conclusion Ourmethod is of high sensitivity, good precision and sound accuracy, and suitable for determination of 14 organochlorine andpyrethroid pesticide residues in fruits.
作者
郭爱华
李晔
李建红
李小丽
王玮
郭蒙京
李敏
GUO Aihua LI Ye LI Jianhong LI Xiaoli WANG Wei GUO Mengjing LI Min Xicheng(District Center for Disease Control and Prevention, Beijing 100120, China)
出处
《中国热带医学》
CAS
2017年第1期50-54,共5页
China Tropical Medicine
