分散液液微萃取技术在食品农药残留检测中的应用研究

发布时间：2018-07-10 14:57

本文选题：悬浮固化-分散液液微萃取(DLLME-SFO) + 空气辅助-分散液液微萃取(AALLME)　；参考：《贵州师范大学》2017年硕士论文

【摘要】：在食品农药残留分析中,样品预处理步骤非常关键。分散液液微萃取(DLLME)技术作为一种新型样品前处理技术,克服了传统样品预处理技术或繁杂耗时、或实验成本过高、抑或处理效果不佳等缺点,满足理想方法所应具备的成本低、准确度高、选择性高、灵敏度高、重现性良好的要求,在其不断发展的过程中,一直备受关注。本文是在总结前人研究工作的基础上,利用三种新型分散液液微萃取方法对食品中的常见农药残留进行了应用分析研究,内容如下:1.建立了悬浮固化-分散液液微萃取-气相色谱法(DLLME-SFO-GC)测定野木瓜中9种有机氯农药残留量的方法。样品经石油醚提取、浓硫酸净化、悬浮固化-分散液液微萃取法浓缩后,用气相色谱-电子捕获检测器(ECD)检测,外标法定量。结果表明,9种农药在1.0~100.0μg/L范围内线性关系良好,相关系数R2在0.99以上,方法检出限(LOD)为0.01~0.07μg/kg。9种有机氯农药在1.75、7.00、28.00μg/kg三个浓度水平添加下,平均回收率范围为83.3~116.7%,相对标准偏差(RSD)范围为1.5~14%。该方法灵敏度高,成功应用于野木瓜中9种有机氯农药残留的测定。2.建立了空气辅助-分散液液微萃取-气相色谱法(AALLME-GC)测定水果中7种有机磷农药残留量的新方法。样品经乙酸乙酯提取、空气辅助-分散液液微萃取法浓缩后,用气相色谱-火焰光度检测器(FPD)检测,采用外标法对有机磷农药残留进行定量。在优化后的实验条件下,7种农药均在40.0~4000.0μg/L范围内线性关系良好,R2在0.99以上,LOD为0.24~1.32μg/kg。采用三个不同浓度水平(12.0、300.0、1000.0μg/kg)进行了加标回收实验,结果表明,7种有机磷农药的平均回收率范围为82.0~114.8%,RSD范围为1.8~15.2%,该方法准确灵敏,成功应用于野木瓜、苹果、梨、葡萄中7种有机磷农药残留的测定。3.开发了一种简便快速的微萃取技术即空气辅助-悬浮固化-分散液液微萃取(AALLME-SFO)用以萃取果汁中4种拟除虫菊酯农药残留。本方法无需分散剂,用少量的低密度有机溶剂作萃取剂,被富集后的分析物经ECD检测,外标法定量。在优化后的实验条件下,4种拟除虫菊酯农药LOD低(0.01~0.03μg/L),在5.0~500.0μg/L范围内线性关系良好,R2在0.99以上。在5、100、400μg/L三个浓度水平添加下,平均回收率范围为82.6~113.6%,RSD范围为1.4~14.1%,以上结果表明,该方法对果汁中四种拟除虫菊酯类农药的测定具有优越的性能。综上,本文对不同类型的DLLME技术进行了研究,通过超声辅助、空气辅助等方式开发了三种新型DLLME技术测定食品中的常见农药残留,对固体基质上DLLME技术的应用进行探索的同时,也极大地提高了分析性能。
[Abstract]:In food pesticide residue analysis, sample pretreatment is very important. Dispersion liquid microextraction (DLLME), as a new sample pretreatment technology, overcomes the disadvantages of traditional sample pretreatment technology, such as excessive time consuming, high experimental cost or poor treatment effect, and meets the low cost of the ideal method. The requirements of high accuracy, high selectivity, high sensitivity and good reproducibility have attracted much attention in the process of its continuous development. On the basis of summarizing the previous research work, three new dispersible liquid microextraction methods were used to analyze the common pesticide residues in food. The contents are as follows: 1. A method for the determination of 9 organochlorine pesticide residues in papaya by suspension solidification, dispersion liquid microextraction and gas chromatography (DLME-SFO-GC) was established. The samples were extracted by petroleum ether, purified by concentrated sulfuric acid, concentrated by suspension solidification-dispersion liquid microextraction, detected by gas chromatography-electron capture detector (ECD) and quantified by external standard method. The results showed that the linear range of nine pesticides was 1.0 渭 g / L, the correlation coefficient R2 was above 0.99. The detection limit (LOD) of the method was 0.01n 0.07 渭 g/kg.9 and the average recovery range was 83.3116.7 渭 g/kg and the relative standard deviation was 1.5%. The method is highly sensitive and has been successfully applied to the determination of 9 organochlorine pesticide residues in papaya. A new method for the determination of seven organophosphorus pesticide residues in fruit by air assisted dispersible liquid microextraction and gas chromatography (AALLME-GC) was established. The samples were extracted by ethyl acetate and concentrated by air-assisted dispersible liquid microextraction. The organophosphorus pesticide residues were determined by gas chromatography-flame photometric detector (FPD) and external standard method. Under the optimized experimental conditions, the linear range of seven pesticides was within the range of 40.0 渭 g / L and 4000.0 渭 g / L, respectively. The linear range of R2 was 0.99 and the LOD was 0.240.32 渭 g / kg 路L ~ (-1) 路L ~ (-1) 路L ~ (-1) 路L ~ (-1). The standard addition and recovery experiments were carried out at three different concentration levels (12.0300.0 渭 g/kg). The results showed that the average recovery range of seven organophosphorus pesticides was 82.0 ~ 114.80.The method was accurate and sensitive, and was successfully applied to wild papaya, apple and pear. Determination of 7 organophosphorus pesticide residues in grape A simple and rapid microextraction technique called air assisted suspension solidification dispersion liquid microextraction (AALLME-SFO) was developed for the extraction of four pyrethroid pesticide residues in fruit juice. In this method, a small amount of low density organic solvent was used as extractant without dispersant. The enriched analytes were detected by ECD and quantified by external standard method. Under the optimized experimental conditions, the LOD of four pyrethroid pesticides was low (0.01 ~ 0.03 渭 g / L), and the linear relationship was higher than 0.99 in the range of 5.0 ~ 500.0 渭 g / L. The average recovery range was 82.6 渭 g / L, 113.6% and 1.4 渭 g / L, respectively. The results showed that the method had excellent performance for the determination of four pyrethroid pesticides in fruit juice. In this paper, three new DLLME technologies were developed to determine common pesticide residues in food by means of ultrasonic and air assisted, and the application of DLLME technology on solid matrix was explored at the same time. It also greatly improves the analytical performance.
【学位授予单位】：贵州师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TS207.53;O658.2

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