QuEChERS-液相色谱-串联质谱法同时测定果蔬中16种农药残留

建立了果蔬中吡虫啉、咪鲜胺、苯醚甲环唑、嘧菌酯、噻虫嗪等16种常见农药多残留的液相色谱-串联质谱(LC-MS/MS)分析方法。以乙腈为提取剂,样品经高速匀浆方法提取后,提取液采用液-液萃取静置分层,取上清液进行净化处理。比较了石墨化碳-氨基复合固相萃取与QuEChERS两种不同净化技术的净化效果,最终确定采用QuEChERS方法为净化手段。即提取液经装有150 mg N-丙基乙二胺(PSA)填料、900 mg无水硫酸镁的净化管净化,除去样品中大部分的色素及有机酸等干扰基质,再经LC-MS/MS分析,有效地降低了样品中的复杂基质所带来的背景干扰。加标水平为5、10、20 μg/kg时,16种农药的平均回收率为75%~111%,相对标准偏差小于16%。16种农药的检出限为0.2~5 μg/kg。采用LC-MS/MS定性分析、基质匹配标准曲线法定量分析,线性关系和回收率结果均令人满意。实验证明,建立的QuEChERS净化与LC-MS/MS相结合的检测方法具有快速、准确、灵敏度高等优点,能够准确测定果蔬中16种农药残留。     

QuEChERS-液相色谱-串联质谱法测定蔬菜中105种农药残留

通过优化QuEChERS前处理方法并结合液相色谱-串联质谱（LC-MS/MS）技术建立了蔬菜中105种典型杀虫剂、杀菌剂、除草剂、植物生长调节剂的多残留测定方法。目标化合物使用乙腈提取,以150 mg乙二胺-N-丙基硅烷（PSA）、150 mg封端十八烷基键合硅胶吸附剂（EC-C₁₈）、30 mg石墨化炭黑（GCB）作为基质提取液净化剂。实验结果表明,在0.010~0.200 mg/L范围内,105种目标化合物的线性相关系数（r）>0.99,方法定量限为0.010 mg/kg;3个添加水平的回收率范围为68.2%~108%,相对标准偏差（RSD）为1.02%~11.8%。该方法快速简便,净化效果好,可用于蔬菜中日常农药残留的测定。     

QuEChERS-高效液相色谱/串联质谱法同时测定茶油中21种农药残留

采用QuEChERS结合液相色谱/串联质谱法建立了茶油中21种农药残留的快速分析方法。样品用乙腈均质提取,PSA和C18净化。对色谱、质谱条件和样品前处理进行了优化。在多反应监测(MRM)模式下进行质谱分析,外标法定量。21种农药在5.0～200μg/L范围内具有良好的线性关系,相关系数均大于0.995。在50,100,200μg/kg水平的平均加标回收率为63.1%～128.6%,RSD为1.6%～15%。21种农药的定量限为0.12～6.93μg/kg。方法适用于茶油中21种农药的定量与定性分析。     

QuEChERS-超高效液相色谱-串联质谱法测定蔬菜中250种农药残留

以QuEChERS为前处理方法,超高效液相色谱-串联质谱为检测仪器,建立了蔬菜中250种农药残留的快速筛查检测方法。采用含1%(v/v)乙酸的乙腈溶液提取样品,以无水硫酸镁(MgSO₄)作为脱水剂,经MgSO₄、丙基乙二胺(PSA)、石墨化碳(GCB)、C18混合净化剂净化,Waters ACQUITY^TM UPLC BEH C18柱(100 mm×2.1 mm, 1.7 μ m)分离,超高效液相色谱-串联质谱进行测定。实验详细考察了MgSO₄、PSA、GCB、C18用量对农药添加回收率的影响,结果表明,2 mL提取上清液中加入300 mg MgSO₄、200 mg PSA、10 mg GCB和100 mg C18时净化效果最好。250种农药在韭菜中3个添加水平下的回收率为60.1%~120.0%,相对标准偏差(RSD)为3.5%~19.5%;检出限为0.01~50.00 μ g/kg。该方法简便、快速、可靠,可用于蔬菜中多种农药残留的快速筛查与确证的日常工作中,具有一定的推广价值。     

QuEChERS-超高效液相色谱-串联质谱法测定坚果中38种农药残留

建立了检测4种坚果(花生、杏仁、腰果、核桃)中38种农药残留的QuEChERS-超高效液相色谱-串联质谱(UPLC-MS/MS)方法.样品均质后,用乙腈进行提取,经PSA和C18净化后,采用Oasis PRiME HLB固相萃取柱进一步净化, UPLC-MS/MS分析.对样品前处理和色谱方法进行了优化.在多重反应监测(MRM)模式下进行质谱分析,外标法定量.38种农药的检出限范围(S/N=3)为0.01~10 μg/kg,定量限(S/N=10)为0.05~20 μg/kg,线性关系良好(r>0.991).4种坚果中农药的平均加标回收率为51.0%~126.0%,相对标准偏差均小于20%.此方法灵敏、准确、有效,可用于坚果类食品中多种农药残留的同时测定.     

液相色谱-串联质谱法快速筛查测定浓缩果蔬汁中的156种农药残留

建立了浓缩果蔬汁中156种农药多残留的液相色谱-电喷雾串联质谱(LC-ESI-MS/MS)测定方法。样品用1%醋酸乙腈溶液萃取,经Waters Sep-Pak Vac固相萃取柱净化,乙腈-甲苯(体积比为3∶1)洗脱,旋转蒸发浓缩,用乙腈-水（体积比为3∶2）溶解,以Agilent ZORBAX SB-C18色谱柱分离,以电喷雾电离串联质谱在正离子多反应监测(MRM)模式下进行测定。对156种农药在5种浓缩果蔬汁(橙汁、苹果汁、葡萄汁、白菜汁、胡萝卜汁)中两个添加水平下的回收率进行了测定,回收率范围为57.2%～122.7%,相对标准偏差范围为0.9%～19.8%。方法的检出限(S/N=3)和定量限(S/N=10)范围分别为0.10～56.77 μg/kg和0.33～189.23 μg/kg。该方法样品前处理简单、快速、分析时间短,灵敏度、准确度和精密度均符合农药多残留检测技术的要求,适用于苹果汁、橙汁、葡萄汁、白菜汁、胡萝卜汁等浓缩果蔬汁中156种农药多残留的快速筛查测定。     

QuEChERS-高效液相色谱-串联质谱法同时测定芝麻油中7种农药残留

采用分散固相萃取QuEChERS前处理方法,结合高效液相色谱-串联质谱(HPLC-MS/MS),建立了精甲霜灵、丁草胺、乙草胺、异丙甲草胺、氟环唑、嘧菌酯、高效氟吡甲禾灵7种常用于油料作物的农药在芝麻油中的多残留分析方法。针对芝麻油基质的复杂性,对目标农药在芝麻油基质中的提取溶剂、净化剂种类进行筛选及优化,最终确定用10 mL乙腈涡旋提取一次,组合60 mg N-丙基乙二胺(PSA)和20 mg石墨化碳黑(GCB)去除芝麻油中脂肪、色素等干扰物,并利用HPLC-MS/MS进行定量分析。芝麻油中7种目标农药在0.001～10 mg/L浓度范围内呈良好线性关系,线性相关系数R²>0.99;7种目标农药在芝麻油中3个添加水平的平均回收率在86.9%～106.3%之间,RSD<5.2%,准确度、精密度和灵敏度均满足农药残留检测的要求。本研究建立的快速、简便、环保的方法适用于芝麻油中目标残留农药定量分析。     

QuEChERS-超高效液相色谱-串联质谱法测定蔬菜中41种农药残留

采用QuEChERS-超高效液相色谱-串联质谱技术,建立了蔬菜中常见的隐性农药、禁限用农药、植物生长调节剂等检出率较高的41种农药残留的测定方法。蔬菜样品用1%(v/v)乙酸-乙腈溶液提取,乙二胺-N-丙基硅烷(PSA)净化后直接进样分析,采用正、负离子多反应监测(MRM)模式,外标法定量。结果表明,在优化后的QuEChERS、色谱和质谱条件下,41种农药在1.0~100 μg/L范围内线性关系良好,相关系数(r²)大于0.999,检出限为0.003~1.00 μg/kg,不同基质中的平均回收率范围为74.1%~120.4%,相对标准偏差(RSD)范围为2.8%~11.9%。该方法快速简便、灵敏度高、净化效果好,可用于蔬菜中41种农药的快速测定,为蔬菜质量安全风险评估工作提供了有力保障。     

QuEChERS-气相色谱-串联质谱法测定枸杞中农药残留

建立了QuEChERS-气相色谱-串联质谱法测定枸杞中农药残留的分析方法。样品经乙腈提取，采用乙二胺-N-丙基硅烷（PSA）、C18和石墨化炭黑（GCB）3种吸附剂净化，在多反应监测模式（MRM）下进行检测，基质外标法定量。结果显示，检测项目在5~500 μg/L范围内呈良好线性（R²>0.99），在3个添加水平下测得回收率为71.5%~109.7%，相对标准偏差（RSD）为1.94%~9.87%（n=6）。该方法灵敏度高、净化效果好，可同时快速检测有机磷类、有机氯类农药。     

QuEChERS-气相色谱/串联质谱法同时测定杨桃中37种农药残留

建立了QuEChERS-气相色谱/三重四极杆串联质谱(GC-MS/MS)测定杨桃中37种农药残留量的方法.样品以1％乙酸乙腈为提取溶剂,采用QuEChERS净化,在质谱多反应监测(MRM)模式下进行定性,基质匹配标准曲线外标法定量.结果表明:在0.01～0.5 mg/L范围内,37种农药的线性关系良好,方法定量限均低于0.01 mg/kg;在低、中、高3个添加水平范围内平均回收率在72.9％～117％之间,相对标准偏差(RSD)≤9.6％.该方法简单、快速、溶剂用量少、灵敏度高,适用于分析杨桃样品中37种农药残留量的检测和确证.     

Comparison of QuEChERS sample preparation methods for the analysis of pesticide residues in fruits and vegetables

This article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography (GC and LC) coupled to mass spectrometry (MS) for detection. The sample preparation approach is known as QuEChERS, which stands for “quick, easy, cheap, effective, rugged and safe”. The three compared versions were based on the original unbuffered method, which was first published in 2003, and two interlaboratory validated versions: AOAC Official Method 2007.01, which uses acetate buffering, and European Committee for Standardization (CEN) Standard Method EN 15662, which calls for citrate buffering. LC–MS/MS and GC–MS analyses using each method were tested from 50 to 1000 ng/g in apple–blueberry sauce, peas and limes spiked with 32 representative pesticides. As expected, the results were excellent (overall average of 98% recoveries with 10% RSD) using all 3 versions, except the unbuffered method gave somewhat lower recoveries for the few pH-dependent pesticides. The different methods worked equally well for all matrices tested with equivalent amounts of matrix co-extractives measured, matrix effects on quantification and chemical noise from matrix in the chromatographic backgrounds. The acetate-buffered version gave higher and more consistent recoveries for pymetrozine than the other versions in all 3 matrices and for thiabendazole in limes. None of the versions consistently worked well for chlorothalonil, folpet or tolylfluanid in peas, but the acetate-buffered method gave better results for screening of those pesticides. Also, due to the recent shortage in acetonitrile (MeCN), ethyl acetate (EtOAc) was evaluated as a substitute solvent in the acetate-buffered QuEChERS version, but it generally led to less clean extracts and lower recoveries of pymetrozine, thiabendazole, acephate, methamidophos, omethoate and dimethoate. In summary, the acetate-buffered version of QuEChERS using MeCN exhibited advantages compared to the other tested methods in the study.     

Simple and rapid method for the determination of ethylenebisdithiocarbamate fungicides in fruits and vegetables using liquid chromatography with tandem mass spectrometry

A simple and rapid method for determining ethylenebisdithiocarbamates (EBDCs; mancozeb, maneb, and zineb) in fruits and vegetables is described. EBDCs are transformed into dimethylethylenebisdithiocarbamate (EBDC-dimethyl) by methylation after their decomposition with ethylenediaminetetraacetic acid (EDTA). These processes were performed simultaneously in this method. Dimethyl sulfate was used as the methylation reagent, and acetonitrile extracts obtained from partitioning with anhydrous magnesium sulfate and sodium chloride were subjected to dispersive solid-phase extraction with the primary secondary amine sorbent. Liquid chromatography with tandem mass spectrometry in the positive heated-electrospray ionization mode was used for the determination of EBDC-dimethyl produced from EBDCs. The method was validated at levels of 10, 50, and 100 ng g⁻¹ maneb as a representative EBDC. The recoveries of the present method were between 71 and 101%. The limits of detection and quantification were 0.24 and 0.8 ng g⁻¹ maneb, respectively.     

QuEChERS/液相色谱-串联质谱法测定5种蔬菜中17种氨基甲酸酯类农药的基质效应研究

建立了QuEChERS/液相色谱-串联质谱法测定5种蔬菜中17种氨基甲酸酯农药残留的方法,研究了该方法下姜、大葱、黄瓜、胡萝卜和白菜对17种农药的基质效应,并探讨了基质种类、基质浓度、农药浓度对基质效应的影响。结果表明:不同基质中的17种氨基甲酸酯农药在5~100μg/L浓度范围内线性关系良好,平均回收率为76.5%~111.8%,相对标准偏差(n=6)为2.5%~8.2%。5种常见蔬菜对17种氨基甲酸酯农药均存在不同程度的基质效应,且多数呈基质抑制效应,其中,基质种类、基质浓度和农药浓度均会影响基质效应强度。胡萝卜对硫双威和乙霉威、黄瓜对硫双威的基质效应均在0.8~1.1之间,日常检测中,可根据实际需求忽略其基质效应影响。但对于其他蔬菜中氨基甲酸酯类农药的检测,必须考虑基质效应的影响。     

防晒类化妆品中2种帕地马酯的高效液相色谱检测及质谱确证

建立了同时测定防晒类化妆品中帕地马酯A和帕地马酯O的高效液相色谱分析方法及质谱确证方法。化妆品样品以甲醇为提取溶剂进行超声提取,提取液离心处理,取上清液经微孔滤膜过滤后测定。采用XTerra MS C18柱(250×4.6mm,5μm)分离,外标法定量。结果表明防晒类化妆品中帕地马酯A和帕地马酯O的方法定量限均为0.5mg/kg,在低、中、高3个添加水平范围内平均回收率为89.1%~112.5%,相对标准偏差为2.0%~7.7%。对于疑似阳性样品,进一步采用液相色谱-串联质谱法进行确证分析。该方法准确、快速、灵敏度高,适用于防晒类化妆品的实际检验工作。     

改良QuEChERS方法快速测定果蔬中8种新型琥珀酸脱氢酶抑制剂类杀菌剂

建立了一种同时测定果蔬中啶酰菌胺、吡噻菌胺、吡唑萘菌胺、氟唑菌酰胺、联苯吡菌胺、氟唑环菌胺、氟唑菌苯胺和氟吡菌酰胺8种新型琥珀酸脱氢酶抑制剂类杀菌剂残留量的液相色谱-串联质谱方法。通过比较乙二胺-N-丙基硅烷（PSA）和十八烷基键合硅胶吸附剂（C₁₈）两种分散固相萃取剂不同添加剂量下的吸附作用和净化效果,优化QuEChERS方法净化过程,以乙腈-0.1%（体积分数）甲酸水溶液为流动相进行梯度洗脱,使8种目标化合物在Poroshell 120 EC-C₁₈色谱柱上分离,经电喷雾正/负双离子扫描、多反应监测模式质谱检测,外标法定量。8种目标化合物在0.5~500.0 μg/L范围内线性关系良好,相关系数均大于0.998,方法检出限为0.2~1.7 μg/kg,定量限为0.5~5.0 μg/kg。各种目标化合物在8种基质中3个添加水平（5.0、25.0和125.0 μg/kg）下的回收率为71.4%~121.3%,相对标准偏差（RSD,n=6）为0.8%~17.2%。该方法操作简单、净化效果好,适用于果蔬中新型琥珀酸脱氢酶抑制剂类杀菌剂的快速检测。     

Optimization of LC-MS/MS using triple quadrupole mass analyzer for the simultaneous analysis of carbosulfan and its main metabolites in oranges

This paper describes an analytical method involving a simple solvent extraction for the simultaneous liquid chromatography coupled to quadrupole tandem mass spectrometry (LC-MS/MS) determination of carbosulfan, its most toxic metabolite -carbofuran -, and its other main metabolites - 3-hydroxycarbofuran, 3-ketocarbofuran, 3-hydroxy-7-phenolcarbofuran, 3-keto-7-phenolcarbofuran, 7-phenolcarbofuran and dibutylamine - in oranges. Chromatography was performed on a Zorbax Bonus-RP (150 mm × 2.1 mm, 5 μm). The mobile phase was a ternary gradient water-methanol-acetonitrile with 1.0 mM ammonium acetate at flow rate of 0.2 ml min⁻¹. The LC separation and MS/MS optimization were studied to select the most appropriate operating conditions. The method developed has also been validated. The limits of quantification (LOQs) were from 1 μg kg⁻¹ for carbofuran to 10 μg kg⁻¹ for 3-keto-7-phenolcarbofuran. Extracts spiked with carbosulfan and its metabolites, at LOQ level, yielded average recoveries in the range 60-94%, with relative standard deviations (R.S.D.s) less than 15%. Calibration curves for carbosulfan and its metabolites (range LOQ-1000LOQ) were linear, with coefficients of correlations better than 0.990. The method was successfully applied to establish the primary degradation products in oranges treated with carbosulfan. The LC-MS/MS method developed is simple, rapid, and suitable for the quantification and confirmation of carbosulfan and seven of its main metabolites in orange at levels lower than 10 μg kg⁻¹.     

QuEChERS样品前处理-液相色谱-串联质谱法测定蔬菜中66种有机磷农药残留量方法评估

比较了两种版本QuEChERS方法(即发表于2003年未加缓冲盐的原创QuEChERS方法及加乙酸盐缓冲液的AOAC 2007.01方法)提取蔬菜中66种有机磷农药(OPPS)的有效性;考察了乙二胺-N-丙基硅烷(PSA)及C18吸附剂对66种OPPS的吸附作用;以提取后添加法评估了青花菜、番茄、枝豆、萝卜、大葱基质中各目标物液相色谱-串联质谱(LC-MS/MS)分析的基质效应。结果表明,加入乙酸盐缓冲液的QuEChERS方法对一些OPPS有较高及较稳定的回收率;PSA及C18吸附剂可吸附二溴磷,QuEChERS样品前处理方法不适于二溴磷分析;5种样品基质中青花菜的基质效应最大。据此采用AOAC 2007.01方法并优化LC-MS/MS分析参数,一次进样监测132对离子对(每个化合物2对离子对)分析蔬菜中66种OPPS残留量,除二溴磷外,65种OPPS在5种基质(青花菜、番茄、枝豆、萝卜、大葱)、3个添加水平(10、40、80 μg/kg)的回收率为55%～122%,相对标准偏差为1.6%～18%,定量限(以信噪比(S/N)≥10计)为0.1～8 μg/kg。以上结果说明该法有效、耐用、灵敏,符合法规残留限量监测要求。