摘要本实验采用超高效液相色谱仪,建立并优化了检测小麦籽粒中吡虫啉残留量的方法。其方法是先用超纯水浸润小麦籽粒,以乙腈作为提取剂用振荡提取的方法从小麦籽粒样品中提取吡虫啉。其次通过氨基柱净化并过0.45 μm的微孔滤膜。最后使用配有紫外检测器的超高效液相色谱仪在270 nm条件下进行测定,其方法是在流动相为甲醇+水=30+70的混合液等度洗脱。从液相色谱图中可辨别出是否有吡虫啉残留。实验进行了三个添加水平测试,分别为0.025 mg/kg、0.05 mg/kg和0.1 mg/kg,得到平均添加回收率为100.7 %~104.0 %,相对标准偏差为2.0 %~3.8 %。仪器能测得的最低检出限为0.006 mg/kg,能测定的最低定量限为0.020 mg/kg。该方法的准确性、精确性以及灵敏度符合农药残留分析测定的要求。7302
关键字 小麦籽粒;吡虫啉;残留分析;液相色谱;
The experiment of imidacloprid in wheat and soil
Abstract:The research established a method of the determination of imidacloprid residues in wheat grain by an Ultra Performance Liquid Chromatography (UPLC). Sample preparation consisted of wetting wheat grain with ultra-pure water and acetonitrile extraction of imidacloprid from the wheat grain by the way of oscillation extraction, followed by purification of the obtained wheat grain on an amino column, and filtered with 0.45 μm filter membrane before use. And then detect the imidacloprid by the UPLC system which equipped with PDA detector at 270 nm. The UPLC method has been developed on reversed phase for separation of imidacloprid with isocratic elution with the mixture of methanol and ultra-pure water (30:70, v:v). The chromatogram data allow the identification of imidacloprid residue. The precision and accuracy were determined by analyzing the recovery of standard imidacloprid in wheat grain samples at three different concentration levels (0.025 mg/kg, 0.05 mg/kg, 0.1 mg/kg) and the results showed that the recoveries for imidacloprid were in a range of 100.7 %~104.0 % with the RED 2.0 %~3.8 %. The limits of detection were 0.006 mg/kg and the limits of determination were 0.020 mg/kg. This indicated that the proposed method could be used for the analysis of imidacloprid in wheat grain with good accuracy and sensitivity.
keywords:wheat grain;imidacloprid;determination of residue;UPLC;
目 录
1 前言 1
1.1 开题依据 1
1.2 农药的发展历程 1
1.3 新烟碱类杀虫剂的发展历程 2
1.4 新烟碱类杀虫剂的抗性及治理 4
1.5 新烟碱类杀虫剂的发展趋势 5
1.6 文献综述 5
1.6.1 吡虫啉的理化性质 5
1.6.2 吡虫啉的剂型 5
1.6.3 吡虫啉剂型的发展趋势 7
1.6.4 吡虫啉杀虫剂的作用机理 8
1.6.5 应用状况 9
1.6.6 动物毒性 9
1.6.7 环境影响 11
1.6.8 分析方法及限量标准 12
1.7 现代农药残留检测仪器分析方法 13
1.7.1 气相色谱法(GC) 13
1.7.2 高效液相色谱法(HPLC) 13
1.7.3 超临界流体色谱(SFC)技术 13
1.7.4 液相色谱-质谱联用技术(LC/MS) 14
1.7.5 毛细管电泳(CE) 14
1.8 超高效液相色谱的认识 14
1.8.1 高效液相色谱仪的原理 14
1.8.2 高效液相色谱仪的应用 15
1.8.3 超高效液相色谱仪的特点 15
1.9 研究目的和意义 16
2 实验准备 17
2.1 试剂与材料 17