分散液液微萃

发布时间：2018-12-20 21:20

【摘要】：食品中农药残留的积累严重影响了人类的身心健康,建立简单有效的检测方法至关重要。分散液液微萃取是一种新型的前处理方式,具有有机溶剂用量少、操作简单、富集倍数高、灵敏度高等优点,本文采用分散液液微萃取的前处理方式结合气质联用、液质联用的多反应监测模式,检测食品中酰胺类除草剂、有机磷及新型杀虫剂的残留,有效地降低了基质的影响。主要的研究内容及结果如下:1.采用盐析-涡旋辅助分散液液微萃取-气质联用快速测定食品中的8种酰胺类除草剂的残留,多反应监测模式,外标法定量分析。探究分散液液微萃取-气相色谱-质谱的最佳条件,对萃取剂和分散剂的种类、体积,涡旋时间、离子强度及离心时间进行了优化。最佳条件:分散剂为9.5 m L乙腈,萃取剂为30μL溴苯,涡旋5 s,4000 r/min离心6 min。8种酰胺类农药的检出限范围为0.03~0.6 ng/L,定量限为1.0ng/L,相关系数0.992,富集倍数为3480~3920,日内、日间相对标准偏差9.6%,加标250 ng/L、750 ng/L,样品回收率为87~103%,萃取效率高,方法重复性好,适合蔬菜茶叶等农药残留分析。2.采用盐析-涡旋辅助分散液液微萃取-液质联用测定茶叶、果汁中6种有机磷农药残留,以甲醇-水为流动相(含0.1%甲酸),质谱正离子多反应监测模式,外标法定量分析。实验对分散液液微萃取方法中的萃取剂、分散剂的种类和体积,前后涡旋时间、离子强度等条件进行了优化,最佳条件:7.5 mL正丙醇为分散剂,30μL 1-溴-3-甲基丁烷为萃取剂,离子强度加NaCl 0.5 g,前涡旋时间2 min,后涡旋时间为50 s。6种有机磷检出限范围是10~25 ng/L,定量限为50.0 ng/L,相关系数0.990,富集倍数约为3640~4120,日内、日间相对标准偏差10.6%,加标200 ng/L、800 ng/L进行回收实验,回收率为85~107%。是一种简便、快速的农药多残留分析方法。3.建立一种微固相萃取-分散液液微萃取-液质联用的检测茶叶、果汁中4种杀虫剂的农药残留的分析方法,以乙腈-水为流动相(含0.1%甲酸),质谱采用正离子多反应监测模式,外标法定量分析。采用金属有机骨架纳米材料做固相萃取吸附剂,减少了基质的影响,极大程度上提高了灵敏度。实验主要从纳米材料的种类、用量、萃取剂和分散剂的种类和用量、涡旋时间等方面优化实验条件,最佳条件:150 mg MIL-100(Fe),乙腈为洗脱剂和分散剂,1.3 mL/次,洗脱3次,40μL溴苯为萃取剂,涡旋时间50 s,4种合成类杀虫剂检出限范围是0.3~0.6 ng/L,定量限为1.0 ng/L,相关系数0.993,富集倍数约为890~990,日内、日间相对标准偏差9.3%,加标250 ng/L、750 ng/L进行回收实验,回收率为88~103%。该方法有机溶剂用量少,基质影响小,富集倍数和灵敏度高,适用于食品中较复杂基质的农药残留检测。
[Abstract]:The accumulation of pesticide residues in food seriously affects the physical and mental health of human beings. It is very important to establish a simple and effective method for the determination of pesticide residues. Dispersion liquid microextraction is a new pretreatment method, which has the advantages of less organic solvent consumption, simple operation, high enrichment factor, high sensitivity and so on. In this paper, dispersion liquid microextraction is combined with GC-MS. The multi-reaction monitoring model with liquid-mass spectrometry was used to detect the residues of herbicides, organophosphorus and new insecticides in food, which effectively reduced the effect of substrate. The main contents and results are as follows: 1. The residues of 8 kinds of amide herbicides in food were determined rapidly by salting-vortex assisted dispersible liquid microextraction and GC-MS. The multi-reaction monitoring model and external standard method were used for quantitative analysis. The optimum conditions of dispersible liquid-liquid microextraction-gas chromatography-mass spectrometry (GC-MS) were investigated, and the types, volume, vortex time, ionic strength and centrifugal time of extractant and dispersant were optimized. The optimum conditions were as follows: dispersant was 9.5 mL acetonitrile, extraction agent was 30 渭 L bromobenzene, vortex 5 s-1 4 000 r/min centrifugation 6 min.8 amides, the detection limit was 0.03? 0. 6 ng/L, quantitative limit was 1.0 ng / L. The correlation coefficient was 0.992, the enrichment multiple was 3480 ~ 3920, the relative standard deviation was 9.6, the recovery rate of the sample was 87 ~ 103, the extraction efficiency was high, and the method was reproducible. Suitable for pesticide residue analysis of vegetables, tea, etc. 2. Six organophosphorus pesticide residues in tea juice were determined by salting-vortex assisted dispersive liquid microextraction and liquid-mass spectrometry. The mobile phase of methanol-water (containing 0.1% formic acid) was used. Quantitative analysis of external standard method. The extractant, the type and volume of dispersant, the vortex time and ionic strength were optimized. The optimum conditions were as follows: 7.5 mL n-propanol was used as dispersant. 30 渭 L 1-bromo-3-methylbutane was used as extractant, ion strength and NaCl were 0.5 g, and the detection limit of 50 s. 6 organophosphorus was 50 s. 6 after 2 min,. The quantitative limit of 10 ~ 25 ng/L, was 50.0 ng/L,. The correlation coefficient was 0.990, and the enrichment multiple was about 3640 ~ 4120. Within days, the relative standard deviation between days was 10.6 and the recovery rate was 85 ~ 1070.The recovery rate was 85,1070.The correlation coefficient was 0.990 and the relative standard deviation was 10.6. It is a simple and rapid method for multiresidue analysis of pesticides. A method for the determination of pesticide residues in tea and juice by microsolid phase extraction-dispersion liquid microextraction and liquid-mass spectrometry was established. Acetonitrile-water was used as mobile phase (0.1% formic acid). The mass spectrometry adopts the positive ion multi-reaction monitoring mode, and the external standard method is used for quantitative analysis. Using organometallic nanomaterials as solid phase extraction adsorbent, the influence of matrix is reduced, and the sensitivity is greatly improved. The experimental conditions were optimized from the aspects of the kinds and amounts of nano-materials, the kinds and amounts of extractant and dispersant, the vortex time and so on. The optimum conditions were as follows: 150 mg MIL-100 (Fe), acetonitrile as eluent and dispersant, 1.3 mL/, etc. Three times elution, 40 渭 L bromobenzene as extractant, and the detection limit of 40 渭 L bromobenzene as extractant. The detection limit of 40 渭 L bromobenzene was 0. 3N 0. 6 ng/L,. The correlation coefficient was 0. 993, and the enrichment multiple was about 89. 990, within a day. The recovery experiment was carried out by adding standard 250 ng/L,750 ng/L, and the recovery rate was 88% 103.The relative standard deviation (RSDs) was 9.3% during the day. The method is suitable for the determination of pesticide residues in more complex matrix in food because of its small amount of organic solvent, little influence on matrix, high enrichment factor and high sensitivity.
【学位授予单位】：山西大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TS207.53;O657.63

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