MSPD在农药残留分析中的应用进展

基质固相分散是近年来研发的检测蔬菜、水果中农药残留的提取和净化前处理技术,净化过程无需预淋洗、淋洗、洗脱等繁杂步骤。本文简要介绍了基质固相分散法的原理及影响因素并结合当前MSPD技术的最新进展,介绍了MSPD技术在农药残留分析时样品前处理上的应用实例。最后指出了应用中存在的问题以及发展趋势。     

MSPO在农药残留分析中的应用进展

基质固相分散是近年来研发的检测蔬菜、水果中农药残留的提取和净化前处理技术,净化过程无需预淋洗、淋洗、洗脱等繁杂步骤.本文简要介绍了基质固相分散法的原理及影响因素并结合当前MSPD技术的最新进展,介绍了MSPD技术在农药残留分析时样品前处理上的应用实例.最后指出了应用中存在的问题以及发展趋势.     

固相微萃取技术的原理及应用

本文所介绍的固相微萃取技术是一项无溶剂样品制备方法，其原理是利用分析组分在样品基质提取与提取剂中的分配不同，从而达到分离目的，具有简便，经济，不使用溶剂等优点，并且能做到提取，净化浓缩和ＧＣ上进样分析同步完成，本文还对固相微萃取的装置，工作程序及应用作了介绍。     

茶叶中7种有机氯和拟除虫菊酯类农药残留检测技术研究

本文对茶叶中7种有机氯类和拟除虫菊酯类农药残留检测的前处理技术进行了研究,对比了2种不同的提取溶剂对农药回收率、净化效果的影响,建立了丙酮∶正己烷(1∶1,V/V)提取,Florisil固相萃取小柱净化的方法。本方法回收率在82.3～109.8%之间,变异系数3.3～10.22%,最低检出浓度为0.001mg/kg。该种残留分析前处理方法具有操作简便、成本低、回收率高、精密度好的特点。     

农产品农药残留检测前处理技术研究进展

由于农产品中农药残留的多样性和复杂性,样品前处理成为农药残留检测的重点和难点.文章主要介绍了近年发展起来的固相萃取小柱、固相微萃取、分子印迹固相萃取、凝胶渗透色谱等前处理技术在农产品农药残留分析中的应用,并展望了农产品前处理技术未来的发展方向.     

固相萃取-气质联用测定茶叶中的26种农药残留

本文研究了固相萃取-气质联用方法测定茶叶中农药残留的方法。用乙睛从茶叶中提取,固相萃取净化26种农药残留,运用GC/MS进行分析。以内标法定量,加标浓度分别为0.01、0.10、1.00mg/kg时,回收率在75.06%~108.26%之间,相对偏差≤10%。方法检出下限为0.01~0.05μg/mg,用该方法可实现对茶叶中农药残留的检测。     

基质固相分散-高效液相色谱法测定玉米中 7种苯氧羧酸类除草剂的残留

采用基质固相分散-高效液相色谱法(MSPD-HPLC)测定了7种苯氧羧酸类除草剂在玉米中的残留。玉米样品与基质固相分散介质C18化学键合硅胶(ODS)一起研匀得到基质固相分散体系,将其填入事前装有弗罗里硅土的净化柱中,以环己烷洗去油脂等杂质,再用乙酸乙酯洗脱得到分析液;在反相高效液相色谱(RP-HPLC)柱上,分析液经ODS柱以甲醇-水(体积比65∶ 35)为流动相洗脱,用紫外检测器检测,以外标法定量。在0.1和1.0 mg/kg添加水平下,7种苯氧羧酸类除草剂在玉米中的添加回收率为80% ~110%,相对标准偏差RSD为3.6% ~10.3%,检出限在7.9 ~12.6 μ g/kg之间。     

茚虫威对映体在番茄、葡萄及水中的液相色谱-串联质谱检测方法

建立了反相条件下茚虫威在对映体水平上的液相色谱-串联质谱(LC-MS/MS)残留分析方法。采用基质匹配标准品的外标法定量,比较分析了基质分散萃取与固相萃取2种净化方法中基质效应的影响。番茄和葡萄样品均采用乙腈提取,NH2/Carb复合固相萃取小柱净化;水样直接采用C18-H固相萃取小柱富集净化。手性拆分的色谱条件为:Chiralpak AD-RH手性分离柱,以V(乙腈)∶V(水)=65∶35为流动相,柱温25 ℃,流速0.4 mL/min。结果表明:在0.005~0.5 mg/kg(水样为mg/L)添加水平范围内,茚虫威对映体在3种基质中的回收率在65.5% ~117.0%之间,相对标准偏差(RSD,n=5)为4.1% ~18.1%。对映体的检出限(LOD)为1.4~4.3 μg/kg(μg/L),定量限(LOQ)为4.7~14.2 μg/kg(μg/L)。方法操作简便,结果稳定可靠,可用于茚虫威对映体在番茄、葡萄和水样品中残留的分析。     

固相萃取-气相色谱-质谱法测定韭菜中16种农药残留

建立了韭菜中16种农药的多残留分析方法。韭菜样本经微波炉加热处理,乙腈提取,新型固相萃取柱Cleanert TPT净化,以气相色谱-质谱-选择离子监测模式测定。结果表明:微波处理、固相萃取净化可以有效去除基质干扰,16种农药在0.02~2 mg/L范围内线性关系良好;在0.01和0.5 mg/kg两个添加水平下的平均回收率分别在84.6%~124.2%和92.4%~98.5%之间,相对标准偏差 (RSD) 均小于20%;16种农药的检出限(LOD)在1~6 μ g/kg范围内。     

土壤和水体中20种除草剂的气相色谱-质谱法多残留分析

建立了土壤和水体中20种除草剂残留的气相色谱-质谱(GC-MS)分析方法。土壤样本通过乙腈提取,Florisil固相萃取柱净化,V(石油醚):V(乙酸乙酯)=9:1洗脱,GC-MS测定;水体样本用C18固相萃取柱进行富集和净化,以V(甲醇):V(乙酸乙酯)=1:1洗脱,GC-MS测定。20种除草剂在土壤和水体中的平均添加回收率分别为72%～109%和77%～113%,相对标准偏差(RSD)分别在0.15%～16.5%和0.45%～16.3%之间,方法定量限(LOQ)在土壤中为0.01 mg/kg,在水体中为0.1 μg/L。用所建方法可同时检测土壤和水中20种常用除草剂,方法净化效果好、灵敏度高、重现性好、简便快速。     

浊点萃取法在农药残留分析中的应用

浊点萃取法是近年来发展较快的一种环境友好型液液萃取技术,与传统的提取方法(如液液分配、固相萃取、索氏提取等)相比,具有高效、低毒、操作简单等优点,目前已成功应用于金属离子、蛋白质、环境样品的前处理和分离、纯化。概述了浊点萃取法的机理和分类(温度诱导的浊点萃取法、凝聚萃取法和混合胶束介质萃取法),总结了近年来该方法在农药残留分析领域环境样品前处理中的应用及其优缺点。     

Determination of tau-fluvalinate residues in honey

A capillary column gas chromatographic method is described for the determination of tau-fluvalinate in honey samples. The method involves solid phase extraction of the sample with two RP C-8 cartridges in series, purification of the extract, if necessary, on a silica cartridge, and detection of the active ingredient with an electron capture detector. The method is rapid and overcomes the problem of emulsion formation in liquid/liquid partition often found in traditional systems. The detection limit in actual samples is 0.01 mg kg^?1 and mean recoveries for fortified samples prepared with or without clean-up are greater than 85%.     

固相微萃取技术进展及其在农药残留分析中的应用

固相微萃取技术是一种无需溶剂、方便快速的样品前处理技术。本文介绍了固相微萃取在设备构造、萃取纤维及涂层材料的开发等方面的发展情况,并对其在农药残留分析中的应用进行了总结。     

HPLC determination of fenoxaprop and fenoxaprop-ethyl in different soils

This paper describes a method for the determination of fenoxaprop ethyl and fenoxaprop residues in four soil types using two extraction procedures: extraction with 0.1 M hydrochloric acid/methanol, partitioning with dichloromethane and extraction with ethyl acetate. The extracts were purified on florisil or alumina cartridge. The analyses were performed by reverse phase HPLC with UV detection at 280 nm. The best results in terms of recovery, clean-up efficiency and independence of soil characteristics were obtained with the combination ethyl acetate extraction alumina clean-up. Under these conditions, the recoveries were higher than 70 % and the detection limit was 0.02 mg kg^?1 soil.     

固相萃取-气相色谱-质谱联用法测定蔬菜中烯肟菌胺的残留及其裂解机理

建立了蔬菜中烯肟菌胺残留量的固相萃取-气相色谱-质谱联用（SPE-GC-MS）分析方法;对烯肟菌胺的裂解机理进行了探讨;确定了测试分析的定性离子和定量离子。样品采用乙酸乙酯高速分散提取,以无水硫酸镁、硅胶和石墨化炭黑（GCB）为混合填料进行固相萃取净化,气相色谱-质谱联用仪在选择离子扫描（SIM）模式下进行检测,基质匹配标准溶液外标法定量。结果显示:烯肟菌胺在0.02~1 mg/L内,标准溶液的峰面积与质量浓度呈良好的线性关系（r>0.999）;在0.02~0.2 mg/kg添加水平下,烯肟菌胺的平均回收率为94%~99%,相对标准偏差（RSD,n=6）为2.3%~2.9%;方法的检出限（LOD）（S/N=3）为0.006 mg/kg,定量限（LOQ）（S/N=10）为0.02 mg/kg。     

Gas-liquid chromatographic method for perfluidone residues in rice grains and husks

A gas-liquid chromatographic method using electron-capture detection is described for the determination of perfluidone residues in rice grains and husks. The procedure consists of extraction, purification on an anion-exchange resin, methylation and further clean-up (if necessary) by adsorption on “Florisil”. The recoveries from fortified rice grains and husks were respectively 73.5–98% and 77–104% in the range 0.01–0.50 mg/kg. Sensitivity permits detection of perfluidone at 0.005 mg/kg level.     

A modified extraction and clean-up procedure for the detection and determination of parathion-methyl and chlorpyrifos residues in tea

Recent advances in methodology and instrumentation have made possible the detection and determination of pesticides at microgram kg-1 (ppb) levels. The sensitivity of a method of analysis depends greatly on the efficient extraction of the pesticide and the subsequent clean-up of the extract. The extract from green tea leaves is a mixture of aroma components, polyphenols and caffeine. The preparation of made tea from green tea leaves adds to this complexity by concentrating these coextractives. Conventional clean-up techniques provide poor recoveries for parathion-methyl and chlorpyrifos from both green tea leaves and made tea. This arises from interference by caffeine during gas chromatography, as it has a similar retention time to the two pesticides and peaks overlap. A modification to the protocol based on a solvent partitioning process using dichloromethane and subsequent washing of the extracts with warm water removed the caffeine, and pigments were removed by column chromatography. Recoveries ranging from 80 to 90% were then obtained for both pesticides.     

Quick estimation of dieldrin in fresh cotton-leaf samples

Hexane was the most convenient extraction solvent. Consistent recoveries of 80% dieldrin were obtained after cold grinding with 10 mi hexane/g of leaf for 5 min. After filtering, solutions did not require a “clean-up” before g.l.c. analysis, provided they were not concentrated further. Radioactive dieldrin in such extracts could be directly counted with a simple scintillation apparatus if pre-treated with acidified potassium permanganate solution to eliminate the colour-quenching effect and stored in the dark for 24 h to allow phosphorescence from some leaf materials to decay. Extractions using other solvents would need a “clean-up” procedure before g.l.c. analysis, but radioactive dieldrin in hexane-isopropanol extracts could be quickly estimated by simple scintillation counting after decolorisation with sodium hypochlorite and storage in the dark for 24 h.