NY/T761-2008标准方法中蔬菜样品前处理过程应注意的问题

<正>NY/T 761-2008《蔬菜和水果中有机磷、有机氯、拟除虫菊酯和氨基甲酸酯类农药多残留的测定》在农残检测中应用最多,该标准前处理方法较简单,但是操作中会出现精密度差、回收率不稳定等现象[1-5],本工作对蔬菜样品前处理过程中有关事项进行了试验,解决了上述问题。1试验部分1.1仪器与试剂布鲁克GC 450型气相色谱仪,配脉冲式火焰(PFPD)检测器,电子俘获(ECD)检测器;FJ-200型     

NY/T761—2008标准中27种农药残留前处理方法的优化

微量化、低毒化、快速化和低成本是样品前处理的发展趋势.建立了果蔬中27种农药残留的快速前处理气相色谱法,对标准NY/T 761—2008中不同种类农药残留的前处理方法进行优化,并对改进后的方法进行可行性研究.使用1％乙酸-乙腈溶液快速提取,采用离心代替原法中过滤与静置,经石墨化炭黑(GCB)净化处理,气相色谱法进行检测...     

参考JJF-1059对农药多残留分析国标方法NY/T761.1-2004的不确定度评价研究

参考JJF-1059<测量不确定度评定与表示>,对农药多残留分析国标方法NY/1761.1-2004(蔬菜和水果中有机磷、有机氯、拟除虫菊酯和氨基甲酸酯类农药多残留检测方法)进行了不确定度的评价研究.对黄瓜基质上的5种有机磷农药(敌敌畏,乐果,甲基对硫磷,毒死蜱,克线磷),应用国标NY/T761方法进行检测.从标准过程、质量称量过程、体积定容和样品处理过程等方面分析农药残留操作环节的不确定度.结果表明,不同农药或浓度水平之间扩展不确定度并没有显著差异,校准过程占整个不确定度的比重随着待测物浓度水平降低而显著提高.     

基于QuEChERS净化/气相色谱法测定蔬菜及水果中16种有机氯农药残留

该文建立了蔬菜及水果中16种有机氯农药残留的QuEChERS净化/气相色谱快速检测方法。样品经1%冰乙酸乙腈处理,QuEChERS净化,气相色谱分离后,以色谱峰保留时间定性,外标法定量。结果表明:16种有机氯农药在2.0~100μg/L质量浓度范围内的线性关系良好,相关系数均大于0.99,检出限为0.16~2.90μg/L,在4种基质(油菜、黄瓜、橙子、苹果)中的加标回收率为70.1%~119%,相对标准偏差(RSD)为0.23%~5.2%。与其它前处理方法相比,该方法简便、快速、准确、高效,可用于蔬菜及水果样品中有机氯残留的高通量快速筛查。     

气相色谱-负化学电离源-飞行时间质谱测定烟草中有机氯农药残留

采用QuEChERS前处理方法,建立了气相色谱-负化学电离源-飞行时间质谱(GC-NCI-TOF-MS)检测烟草中10种有机氯农药残留的分析方法。样品采用乙酸乙酯-正己烷(1 : 1, v/v)溶液提取,提取液经N-丙基乙二胺(PSA)、无水硫酸镁分散固相萃取净化,用GC-NCI-TOF-MS检测分析。根据有机氯化合物特征离子的精确质量数、同位素离子峰簇、碎片离子丰度比和保留时间对目标物定性鉴定,外标法定量。10种有机氯农药的线性关系良好,相关系数 (r²)均大于0.997;相对标准偏差小于6.5%;检出限为0.04~0.80 μ g/kg;加标回收率为77.2%~93.0%。该方法简单快速、灵敏度高、准确性好,适用于烟草中有机氯农药残留的定性分析和定量检测。     

基于QuEChERS净化-气相色谱法同时测定蔬菜中6种有机磷类农药残留

建立了QuEChERS（Quick,Easy,Cheap,Effective,Rugged and Safe）法-气相色谱法测定蔬菜中6种有机磷农药残留量的检测方法.样品用1%乙酸乙腈提取,经N-丙基乙二胺（PSA）和无水硫酸镁分散固相萃取净化,气相色谱火焰光度检测器测定.考察了QuEChERS法在两种不同体系（氯化钠盐析和乙酸盐缓冲体系）的提取净化效果.试验结果表明,在乙酸盐缓冲体系中,有机磷农药残留更加稳定,回收率更高.6种有机磷农药残留在0.2~10.0 mg/L之间线性关系良好,相关系数（R²）均大于0.999,检出限在0.003 5~0.015 mg/L之间.低、中、高3个添加水平的回收率在78.5%~106.3%之间,相对标准偏差在1.4%~6.3%之间.方法简单、快捷,准确可靠,适合大批量样品农残检测.     

全自动QuEChERS样品制备系统结合高效液相色谱-串联质谱法检测植物源性食品中34种农药残留

建立了全自动QuEChERS样品制备系统结合高效液相色谱-串联质谱（HPLC-MS/MS）同时检测植物源性食品中34种农药残留的分析方法。方法利用全自动QuEChERS样品制备系统涡旋振动和离心功能，将手动QuEChERS方法中样品提取和分散固相萃取相结合；优化了操作参数及前处理步骤，在多反应监测（MRM）模式下检测，基质匹配外标法定量。从方法学验证角度对全自动QuEChERS法与手动QuEChERS法进行了比较。结果表明：该方法中大多数农药在一定范围内呈现良好的线性关系，相关系数（R²）均大于0.99，检出限为0.76~3.60 μg/kg，定量限为2.28~10.80 μg/kg，加标回收率为53.0%~125.2%，相对标准偏差（RSD）<15.9%（n=5）。该方法与手动QuEChERS法的方法验证比对结果显示差异不明显，用于植物源性食品中多农药残留检测可有效降低劳动强度和出错概率。     

QuEChERS预处理结合HPLC-MS/MS同时检测茶叶中7种农药残留

本文建立了同时分析检测茶叶中啶虫脒、吡虫啉、噻虫嗪、多菌灵、克百威、灭多威和丁醚脲7种农药残留的QuEChERS前处理结合高效液相色谱-质谱联用(QuEChERS-HPLC-MS/MS)技术.优化了QuEChERS前处理的各种条件和HPLC-MS/MS分离检测条件.所建立的方法简单、快速,可用于同时分析检测茶叶中上述7种农药残留,效果良好.7种农药的国际纯粹与应用化学联合会(IUPAC)定量限为0.26~1.3 ng/m L,回收率为86%~101%,能够满足国内外茶叶标准对其限量指标的检测要求.     

QuEChERS在线凝胶色谱-气相色谱/质谱快速检测水产品中农药多残留

建立了水产品中农药多残留的在线凝胶色谱-气相色谱/质谱(GPC-GC/MS)快速检测方法。样品通过乙腈提取,C18和PSA分散净化等QuEChERS前处理方法和凝胶色谱(GPC)在线净化,采用GC/MS的选择离子监测(SIM)模式,对水产品中8组农药进行同时定性和定量检测。结果表明,有机氯硫丹,有机磷敌百虫、马拉硫磷、水胺硫磷、对硫磷、三唑磷,菊酯氰戊菊酯和三嗪类扑草净农药的浓度在10~1 000μg/L范围内线性关系良好,方法的检出限为10~30μg/kg;空白鲤鱼加标的平均回收率在81.2%~118.5%之间,相对标准偏差(RSD)为2.27%~9.12%;空白对虾加标的平均回收率是71.5%~104.0%,RSD为2.98%~8.45%。该检测方法简单、快速、灵敏度高、具有良好的回收率和可重现性,可用于水产品中农药多残留的快速灵敏检测。     

全自动QuEChERS-LPGC-MS/MS检测茶叶中46种农药残留

建立了全自动QuEChERS样品前处理系统结合低压气相色谱-三重四极杆质谱(LPGC-MS/MS)同时检测茶叶中46种农药残留的分析方法。茶叶样品经粉碎均匀后,用全自动QuEChERS样品前处理系统提取、净化,氮吹浓缩后,用TG-5LPGC-MS柱分离,三重四极杆质谱多反应监测(Multiple Reaction Monitoring,MRM)模式检测目标物,外标法定量。在1倍定量限、2倍定量限和10倍定量限三个添加水平下,选定的空白茶叶样品中的回收率在77.9%～106.3%之间,相对标准偏差(relative standard deviation,RSD)为0.8%～9.4%,方法的检出限(detection of limit,LOD)在0.11～4.3μg·kg^-1。该方法自动化程度高,出错率低,耗时短,有效的节省人力资源成本及实验成本,适用于大批量茶叶样品中多种农药残留的快速定性定量。     

超高效液相色谱-串联质谱法快速检测蔬菜中248种农药残留

采用超高效液相色谱-串联质谱（UHPLC-MS/MS）技术建立了快速检测蔬菜中248种农药残留的分析方法。蔬菜样品采用乙腈提取,盐析后无需净化,缩短了样品前处理的时间。采用正负离子多反应监测（MRM）模式对蔬菜中248种农药残留进行定性和定量分析。245种农药在各自的线性范围内线性关系良好（r>0.99）。除丁硫克百威、灭蝇胺、苯磺隆和二氯喹啉酸4种农药外,其余244种农药在3个添加水平下的平均回收率范围为63.0%～126.4%,相对标准偏差（RSD）范围为0.5%～26.7%,方法的定量限为0.001～0.030 mg/kg。该方法具有简单、快速、灵敏度高、准确度高等优点,适合蔬菜样品中农药多残留的快速检测分析。     

A new analysis method with GC or GC-MS for the quick detection of pesticide residues in vegetables

A new analytical method for gas chromatography (GC) or GC-mass spectrometry (MS) using the direct sampling technique is described. This direct sampling technique, which bypasses the conventional complicated sample pretreatment process, is applicable to cases of fast detection of pesticide residues in foods and large-scale screening of samples by portable GC in field detection. By a direct sampling technique, the vegetable sample is ground into paste, and 30 mg is placed directly into the evaporating chamber for GC-MS identification and quantitation (by full-scan mode). The GC column used is an HP-5 (30.0-m x 250-microm x 0.25-microm, 5% phenyl methyl siloxane). Chlorpyrifos, bromophos, fenpropathrin, gamma-666, and pp'-DDT are chosen to represent organophosphorus, pyrethrins, and organochlorine pesticides because they are chief objects of the detection of pesticide residues in vegetables. Rape, a common and mass-consumed vegetable in China, is chosen as the sample in this study. The detection limits for these pesticides by the full-scan mode are all below the maximum pesticide residue limit of vegetables set by the Ministry of Agriculture of China, and the reproducibility of this method is acceptable. This analysis method is proven to be simple, quick, and reliable and is suitable for multipesticide residues analysis of vegetables. It can also be used in the analysis of vegetable components and signal chemicals.     

Pesticide residue determination in vegetables from western China applying gas chromatography with mass spectrometry

In this study,an effort has been made to evaluate the pesticide residues in vegetables from western China. Fifty‐one pesticides, including organophosphorus, organochlorine, carbamate and pyrethroid, were detected in 369 commonly used vegetables by GC‐MS. Concentrations of organophosphorus pesticides were detected ranging from 0.0008 to 18.8200 mg/kg, among which organophosphorus pesticide concentrations exceeded their maximum residue levels (MRLs) in five samples. Carbamate and organochlorine pesticides were determined to have concentrations in the range of 0.0012–0.7928 mg/kg. The residual concentrations of carbamate pesticides in six samples and organochlorine pesticides in four samples exceeded their MRLs. The residual concentrations of five pyrethroid pesticides were within the range of 0.0016–6.0827 mg/kg and the pyrethroid residues in two samples exceeded their MRLs. The results revealed that pesticide residues in 70.73% of the vegetables samples were not detected, while in the rest of vegetables there were one or more pesticide residues and some even exceeded their MRLs, which would threaten the health of consumers. Our work provides significant information for the food safety regulations to control the excessive use of some pesticides on those kinds of vegetables from western China. Copyright © 2016 John Wiley & Sons, Ltd.     

Monitoring pesticide residues in Egyptian fruits and vegetables in 1995.

Organophosphorus, dithiocarbamates, and some synthetic pyrethroids pesticides, which are commonly used in Egypt for pest control, were monitored, as well as persistent organochlorines, which had been prohibited from use several years ago. Fruit and vegetable samples (397) were collected from 8 local markets and examined for 52 pesticides. Of all analyzed samples, 42.8% contained detectable residues, of which 1.76% exceeded their maximum residue limits (MRLs). The rates of contamination with the different pesticides were 0-86%. However, violation rates among contaminated products were very low, ranging from 0 to 4.6%. In general, organochlorine pesticide residues were not detected in most samples. Dithiocarbamate residues were found in 70.4% of 98 samples analyzed for dithiocarbamates, but only one grape sample had residues exceeding the MRL established by the Codex Committee on Pesticide Residues.     

Comparison of solvent extraction and solid-phase extraction for the determination of organochlorine pesticide residues in water.

Solid-phase extraction (SPE) of organochlorine pesticide residues from environmental water samples was evaluated using octadecyl (C18)-bonded porous silica. The efficiency of SPE of these pesticide residues from reagent water samples at 1-5 micrograms dm-3 levels was compared with those obtained by solvent extraction with hexane and Freon TF (trichlorotrifluoroethane). Average recoveries exceeding 80% for these organochlorine pesticides were obtained via the SPE method using small cartridges containing 100 mg of 40 microns C18-bonded porous silica. The average recovery by solvent extraction with hexane and Freon TF exceeded 90% in both instances. It was concluded that the recoveries and precision for the SPE of organochlorine pesticides were poorer than those for the solvent extraction method. Organochlorine pesticide residue levels in environmental water samples from two major rivers flowing through predominantly rice-growing areas were monitored by gas chromatography using the solvent extraction method with hexane. Exceptionally high levels of organochlorine pesticide residues such as BHC, DDT, heptachlor, endosulfan and dieldrin were found in these water samples.     

改性多壁碳纳米管固相萃取-高效液相色谱法测定农产品中痕量残留的4种有机氯农药

对多壁碳纳米管(MWNTs)的表面进行酸氧化处理制备了改性的MWNTs,并建立了以改性MWNTs作为固相萃取(SPE)吸附剂测定农产品中痕量残留的4种有机氯农药(p,p′-DDD、p,p′-DDT、o,p′-DDT、p,p′-DDE)的SPE-高效液相色谱(HPLC)分析方法。考察了氧化处理条件、SPE操作条件和色谱条件等对有机氯农药残留测定的影响,优化了实验条件。在优化实验条件下,4种农药在较宽线性范围内线性良好,相关系数为0.9978～0.9995,检出限为0.050 mg/L;在样品中分别添加0.10、2.0、50 mg/L的4种农药,其加标回收率为78%～104%,相对标准偏差(RSD)为2.7%～7.6%。MWNTs作为SPE填料用于陈皮、西洋参、卷心菜和茶叶等样品的净化效果良好,测定结果准确,灵敏度高,符合农产品中痕量农药残留的分析方法要求,为农产品中此类农药的痕量残留分析提供了有益的参考。     

快速滤过型净化结合气相色谱-串联质谱法同时检测茶叶中10种拟除虫菊酯农药残留

建立了快速滤过型净化（m-PFC）结合气相色谱-串联质谱（GC-MS/MS）测定茶叶中10种拟除虫菊酯类农药残留的方法。比较了采用不同提取溶剂（乙腈、丙酮和乙酸乙酯）和不同提取方式（不加水浸泡和加水浸泡）时10种农药的提取效率；比较了2种QuEChERS净化管和m-PFC柱对茶叶提取液的净化效果和农药残留的回收率。结果表明，茶叶样品不加水浸泡，用乙腈提取效果最好；m-PFC柱对茶叶提取液净化效果良好，而且能保证较高的农药回收率。10种拟除虫菊酯农药在相应的范围内有良好的线性关系，相关系数（R²）大于0.9980；10种农药在4个水平添加下的回收率为87.5%~111.3%，RSD为2.1%~8.9%。方法的检出限为0.001~0.015 mg/kg，定量限为0.003~0.05 mg/kg。利用该方法检测市售50例茶叶样品中10种拟除虫菊酯农药的残留，检出率为48%，但农药残留量均在国家标准限量值以下。与传统QuEChERS法和固相萃取法相比，该方法具有操作简单、准确度和精密度良好等优点，为多种拟除虫菊酯类农药在茶叶中的残留测定提供了快速检测的新方法。     

Monitoring of pesticide residues in Egyptian fruits and vegetables during 1996

Samples of the most common fruits and vegetables were collected from 8 local markets in 6 governorates. These 1,579 samples were analyzed for residues of 53 pesticides, which included organophosphorus and organonitrogen compounds and some synthetic pyrethroids. Samples were also analyzed for residues of organochlorine pesticides, although they had been prohibited from use several years ago. Only 510 of the 1,579 samples were analyzed for dithiocarbamate pesticide residues, which were determined as CS2. Overall, 76.1 % of the total analyzed samples had no detectable residues, 23.9% contained detectable residues, and 2.59% contained residues that exceeded maximum residue limits. For individual crops, contaminated samples ranged from 0 to 96% of the number of samples analyzed. However, the highest violative percentage for samples of individual crops was 12.5. Chlorpyrifos, carbaryl, dimethoate, bromopropylate, and profenofos were the violative pesticides determined in fruit and vegetable samples. The results of the current study demonstrated that no restricted or banned pesticides such as DDT, HCH, and their isomers were found in any of the samples analyzed. Dithiocarbamate residues were detected in 9.4% of the 510 samples analyzed, with a violative percentage of 0.39, representing one grape sample and one peach sample.