烯草酮在马铃薯和土壤上分布研究
时间:2017-05-21 09:04 来源:毕业论文 作者:毕业论文 点击:次
摘要:本实验采用三级四级杆液质联用仪,建立并优化了马铃薯和土壤中烯草酮的残留分析的方法。经优化后的方法为:在锥形瓶中称取样品5.00 g,加入20.0 mL超纯水,2.0 mL乙酸铅,加入20.0 mL乙腈,在摇床上摇晃2 h后抽滤,盐析,静置分层。取上层清液1 mL,用30 mgC18分散固相萃取填料进行净化,净化后的溶液用0.22 μm微孔滤膜过滤,装入进样小瓶上机。流动相为乙腈-水-甲酸(体积比60∶40∶0.1),流速0.3 mL/min;柱温为35 ℃;进样量4 μL。离子对360.1/164.1为定量离子,对烯草酮残留进行定量分析。实验进行了三个添加水平测试,分别为0.05 mg•kg-1、0.1 mg•kg-1和0.2 mg•kg-1,得到的平均回收率为85.3%~86.8%,相对平均偏差(RSD)小于5%。烯草酮在马铃薯上的最大残留限量为0.1 mg•kg-1,该方法的检出限为0.010 mg•kg-1,定量限为0.020 mg•kg-1,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。8930 关键字:烯草酮,残留分析,液质联用,马铃薯 Distribution of Clethodim in potato and soil Abstract:In this study,we use the three quadrupole LC-MS instrument,the analysis method of clethodim residues in potato and soil is established and optimized.The method after optimization is: weigh 5.00 g sample in the conical flask,add 20.0 mL ultrapure water,2.0 mL lead acetate,20.0 mL acetonitrile, shaking 2 h in a shaker,filtration, salting rested,stratification.Take the supernatant fluid 1 mL,With 30 mgC18 dispersive solid-phase extraction packing for purificatio,after purification, the solution with 0.22 um microporous membrane filter, load the sample vial and Ready to machine.Mobile phase is acetonitrile - water - formic acid (volume ratio 60:40:0.1), the flow rate of 0.3 mL/min; Column temperature of 35 ℃; Sample quantity 4 uL.Ion on 360.1/164.1 is quantitative ion,ion pair 360.1/164.1 as a quantitative ion,analysis residues of clethodim.Experiment was carried out three add level test,respectively are 0.05 mg•kg-1,0.1 mg•kg-1,0.2 mg•kg-1.The average recovery was 85.3% ~ 85.3%, average relative deviation (RSD) is less than 5%.The method detection limit is 0.010 mg•kg-1, quantitative limit is 0.020 mg•kg-1, accuracy, precision and sensitivity of this method meets the requirement of pesticide residue analysis determination. Keywords: Clethodim, residue analysis, LC-MS, potato 目录 1 前言 1.1烯草酮的理化性质..1 1.2烯草酮的生物活性..1 1.3烯草酮的环境影响与动物毒性1 1.4 烯草酮的残留分析方法..2 1.4.1 液相色谱串联质谱法分析..2 1.4.2 近红外光谱法分析..3 1.4.3核磁共振氢谱法分析..3 1.5烯草酮的最大残限度.4 1.6 立题依据..5 2 实验部分 2.1 主要的试剂和仪器设备6 2.1.1 试剂与材料.6 2.1.2 仪器设备..6 2.2 分析步骤6 2.2.1 提取.6 2.2.2 净化.7 2.2.3 测定.7 2.2.3.1 仪器条件.7 2.2.3.2 结果的计算和表达7 2.3标准曲线与检出限度..8 2.3.1标准曲线8 2.3.2检出限与定量限9 3 烯草酮残留分析方法的优化 3.1提取剂对于回收率的影响11 3.2提取方式对于回收率的影响..11 3.3提取剂量对于回收率的影响..12 3.4加水对于回收率的影响.13 3.5加水量对于回收率的影响13 3.6氨基柱和Florisil柱对于回收率的影响14 3.7分散固相萃取填料对标准品的吸附15 3.8C18量对于回收率的影响.15 3.9添加乙酸铅对于回收率的影响..16 4 结论 4.1对马铃薯和土壤样品进行添加回收实验.18 4.2不同添加量的添加回收..19 5 总结..20 6 致谢..21 参考文献22 (责任编辑:qin) |