气相色谱法同时测定玉米中12种三嗪类除草剂的残留量

建立了气相色谱-氮磷检测器同时检测玉米中12种三嗪类除草剂（西玛通、西玛津、阿特拉津、扑灭津、特丁通、特丁津、环丙津、西草净、扑草净、特丁净、甲氧丙净、环嗪酮）残留量的方法。玉米样品用乙腈萃取,强阳离子交换(SCX)固相萃取柱净化后,用DB-5弹性石英毛细管柱(30 m×0.25 mm i.d.×0.25 μm)分离样品,氮磷检测器测定。12种三嗪类除草剂在0.01～2.0 mg/L范围内线性关系关系良好,相关系数均大于0.998;最低检测限为0.01 mg/kg;添加回收率为84.0%～106.8%;相对标准偏差为0.9%～4.7%。     

气相色谱-电子捕获检测器同时测定茶叶中有机氯及拟除虫菊酯类农药残留

在超声波辅助下,以正己烷-二氯甲烷（1：1,V／V）混合溶剂提取样品,提取液用弗罗里硅土和中性氧化铝混合柱净化,用气相色谱-电子捕获检测器（GC-ECD）同时测定茶叶中18种有机氯和9种拟除虫菊酯类农药残留。有机氯农药在0.001-0.2μg／mL,拟除虫菊酯类农药在0.005-1.0μg／mL范围内线性良好。有机氯农药在0.04、0.01μg／mL两个添加水平的回收率分别为89.5％-113.2％和80.0％-112.7％,相对标准偏差分别为3.82％-9.64％和5.32％-13.8％。拟除虫菊酯在0.2、O.05μg／mL两个添加水平的回收率分别为97.5％-129.6％和87.3％-110.2％,相对标准偏差分别为3.78％-10.72％和3.02％-13.84％。本方法快速、灵敏、准确、可靠,用于江西茶叶样品中有机农药残留测定,获得较好结果。     

高效液相色谱法同时测定大豆中10种磺酰脲类除草剂的残留量

首次建立了同时检测大豆中10种磺酰脲类除草剂(环氧嘧磺隆、噻吩磺隆、甲磺隆、醚苯磺隆、氯磺隆、苄嘧磺隆、氟磺隆、吡嘧磺隆、氯嘧磺隆和氟嘧磺隆)多残留量的反相高效液相色谱(RP-HPLC)方法。样品经乙腈提取、正己烷液-液分配、Florisil填充柱净化后,采用RP-HPLC-二极管阵列检测器检测(DAD)法测定,外标法定量。对样品前处理和色谱分离条件进行了详细的研究和优化。10种磺酰脲类除草剂的质量浓度在0.1~10.0 mg/L范围内其浓度与峰面积的线性关系良好,相关系数为0.9996~0.9997;在     

气相色谱-质谱法同时测定土壤中30种农药残留

采用气相色谱-质谱法同时测定土壤中30种农药残留。样品经过丙酮-正己烷(1+1)混合溶液均质提取,再用正己烷进行萃取,弗罗里硅土柱净化后,采用HP-5MS色谱柱分离,选用电子轰击离子源和选择离子监测模式进行质谱分析,外标法定量。30种农药的线性范围为0.1~1.0mg·L-1,检出限(3S/N)为3.8~9.6μg·kg-1。加标回收率在75.8%~103%之间,测定值的相对标准偏差(n=6)在5.6%~9.7%之间。     

气相色谱-质谱法同时测定粮谷及油籽中多种酰胺类除草剂残留量

粮谷及油籽样品经丙酮-水提取,经去脂和弗罗里硅土固相萃取小柱净化,气相色谱-质谱(GC-MS)选择离子监测模式(SIM)对净化液进行检测;一次进样,便可对粮谷及油籽样品中的9种酰胺类除草剂及常混用的莠去津和嗪草酮等除草剂残留进行准确定量和确证。除草剂回收率为63%~96%;相对标准偏差为2.1%~11.2%;定量下限为0.02~0.05 mg/kg。该法快速、灵敏、准确,各项技术指标均满足农药残留检测的要求。     

Determination of Organochlorine Pesticide Residues in Sesame Seeds by GC-ECD

A method for the multiresidue analysis of 12 organochlorine pesticides in sesame seeds has been developed. The organochlorine residues in the seeds were first extracted by accelerated solvent extraction and the extract subjected to gel permeation chromatography to remove larger molecular weight materials such as proteins and waxes. The purified extract after gel permeation chromatography was analyzed by GC-ECD. Recoveries were higher than 75% for all compounds with relative standard deviations <20%. The limit of detection and limit of quantification were 1.6–3.3 and 5–10 ng g⁻¹, respectively.

     

Determination of Organochlorine Pesticide Residues in Sesame Seeds by GC-ECD

A method for the multiresidue analysis of 12 organochlorine pesticides in sesame seeds has been developed. The organochlorine residues in the seeds were first extracted by accelerated solvent extraction and the extract subjected to gel permeation chromatography to remove larger molecular weight materials such as proteins and waxes. The purified extract after gel permeation chromatography was analyzed by GC-ECD. Recoveries were higher than 75% for all compounds with relative standard deviations <20%. The limit of detection and limit of quantification were 1.6–3.3 and 5–10 ng g^?1, respectively.     

固相萃取-高效液相色谱法同时测定大豆和大米中的磺酰脲类和二苯醚类除草剂残留

建立了大豆和大米中磺酰脲类和二苯醚类除草剂多残留同时检测的高效液相色谱分析方法。样品经乙腈提取,正己烷液-液分配,C18固相萃取小柱净化后,采用高效液相色谱方法分离,以乙腈-三乙胺盐酸溶液作流动相,梯度洗脱,紫外检测器检测。对样品前处理和色谱分析条件进行了优化,8种除草剂(甲磺隆、氯磺隆、苄嘧磺隆、吡嘧磺隆、三氟羧草醚、精恶唑禾草灵、乙氧氟草醚、乙羧氟草醚)在0.05~2.0 mg/L范围内线性关系良好。方法的定量限(S/N=10)为0.01~0.02 mg/kg,能达到国家有关上述除草剂残留限量的要求。大豆和大米样品的平均加标回收率分别为91.6%~116.1%和76.6%~110.8%,相对标准偏差(RSD)为1.0%~12.2%。所建立的方法在30 min内可完成一次检测,具有简便快速、灵敏可靠的特点,适用于大豆和大米中除草剂多残留的测定。     

On-Line Preconcentration and Analysis of Metribuzin Residues in Corn Fields by Use of a Molecularly Imprinted Polymer

A molecularly imprinted polymer as a selective solid-phase extraction adsorbent for efficient preconcentration and analysis of metribuzin residues in corn fields has been synthesised and evaluated. Results showed that molecular imprinting of the polymer was highly effective and the polymer had high affinity and selectivity for metribuzin in water-containing systems. A monolithic column containing molecularly imprinted polymer was prepared and used for on-line preconcentration, separation, and detection of metribuzin residues in soil sampled during investigation of the degradation of the herbicide metribuzin in corn fields. The detection limit of the method was 8.3 × 10^?4 mg kg^?1, recovery was between 94.9% and 103%, and RSD in analysis of soil samples was less than 3.2%.     

Determination of Pyrethroid Residues in Pork Muscle by Immunoaffinity Cleanup and GC-ECD

A method was developed to determine six pyrethroids (tau-fluvalinate, fenpropathrin, λ-cyhalothrin, cyfluthrin, α-cypermethrin and deltamethrin) in pork muscle by immunoaffinity column cleanup and gas chromatography-electron capture detection. Spiked pork muscle samples at 5, 20, 50 μg kg^?1 were extracted with petroleum spirit-diethyl ether (1:1, v/v). Fat was eliminated by liquid–liquid partition between acetonitrile and petroleum spirit. An immunoaffinity column (IAC) was used for further cleanup. The IAC column was prepared by coupling the polyclonal antibodies to the protein A sepharose gel and the resulting affinity gel columns were sufficiently stable for multiple reuse. Target compounds were adsorbed at pH 7.4 and after extensive washing, eluted with 3 mL methanol. Recoveries of the six pyrethroids were typically >70%. The detection limit was 2 μg kg^?1 for λ-cyhalothrin and α-cypermethrin and 5 μg kg^?1 for cyfluthrin, deltamethrin, fenpropathrin and tau-fluvalinate. Repeat analyses of pork muscle samples showed good repeatability. The method was applied to detect residues in meat samples.     

气相色谱化学电离二级质谱法测定土壤中16种三嗪类除草剂的残留

建立了气相色谱化学电离二级质谱法(GC-CI-MS/MS)同时测定土壤中16种三嗪类除草剂多残留量的方法,测定16种三嗪类除草剂仅需12min。样品采用乙腈与盐酸混合溶液,加入氯化钠超声波辅助提取,离心后,乙腈层经过国产石墨化炭黑(GCB)柱净化,流出液浓缩后环己烷定容,GC-MS/MS测定。研究比较了在不同进样溶剂下的化合物响应和不同填料固相萃取(SPE)柱的萃取净化效果,结果表明,环己烷作为进样溶剂效果最好,国产GCB和C18-SPE柱的回收率较好,同时国产GCB对色素的净化效果好,替代进口SPE柱,可以节约实验成本。16种三嗪类除草剂在0.05(0.1)～8.0mg/L范围内线性良好,相关系数在0.9952～0.9999之间;在0.005～0.02μg/g添加水平范围内,平均添加回收率在91.41%～114.12%之间;相对标准偏差在1.1%～16.8%之间。本方法中16种三嗪类除草剂在土壤中的检出限均低于0.005μg/g。     

木材及木制品中有机氯杀虫剂残留的GC-ECD法测定

建立了木材及木制品中10种有机氯杀虫剂残留的气相色谱测定方法。样品经粉碎后,用丙酮-正己烷(体积比1∶9)超声提取20 min,以3 000 r/min离心5 min,重复提取1次,上清液经浓缩、脱水后供气相色谱测定。采用HP-5毛细管气相色谱柱进行分离,ECD检测器进行检测。方法在5~500μg/L的范围内线性关系良好,除4,4′-DDT外,线性相关系数均大于0.995。10种有机氯杀虫剂在松木及密度板空白基质中的加标回收率为89%~110%,相对标准偏差小于8.9%。该方法检出1种白橡木实木样品中含有γ-HCH,含量平均值为0.850 mg/kg,相对标准偏差为1.9%;1种复合木地板样品中含有氯丹杀虫剂,含量平均值为109.134 mg/kg,相对标准偏差为4.7%。该方法操作简单、高效,且灵敏度高、精密度好。     

对土壤及玉米植株中均三氮苯类除草剂的残留分析

土壤或玉米植株样品用Ｖ（甲醇）∶Ｖ（乙腈）＝１∶１提取,提取液用石油醚净化后,浓缩液过Ｃ１８小柱净化,最后用Ｎｏｖａ－ＰａｋＣ１８柱进行ＨＰＬＣ分析。回收率：氰草津为８２．４％～９９．８％,莠去津为８５．６％～１０２．３％,西草净为８９．１％～１０８．４％。     

Determination of Cypermethrin Residues in Crucian Carp Tissues by MSPD/GC-ECD

A sensitive matrix solid-phase dispersion (MSPD)/gas chromatography-electron capture detector (GC-ECD) method was developed to determine cypermethrin residues in three tissues (muscle, liver, and gill) of crucian carp. Cypermethrin was simultaneously extracted by MSPD and determined by GC-ECD. The main parameters affecting extraction yield and selectivity, such as the type of solid adsorbent material, choice of elution solvents and their volume, were investigated to obtain interference-free extracts and quantitative cypermethrin recovery. Fortified recoveries in muscle, liver, and gill samples ranged from 84.9% to 106.1%, and relative standard deviations were <8% with fortification levels of 0.05–1 mg kg^?1. Detection limits were 1.4–2.1 μg kg^?1, and quantitation limits were 5.8–7.8 μg kg^?1. The proposed method was successfully applied to determination of cypermethrin in fish tissue samples.     

固相萃取-高效液相色谱法同时检测大米中12种磺酰脲类除草剂的残留

建立了固相萃取前处理净化技术-高效液相色谱（HPLC）同时检测大米中12种磺酰脲类除草剂残留的方法。采用ENVITM-18(C18)硅胶柱和ENVI-Carb(GCB)石墨化碳柱对样品进行净化、萃取,采用C8柱,以乙腈和5 mmol/L 冰乙酸混合溶剂为流动相进行梯度洗脱,在240 nm下进行检测。12种磺酰脲类除草剂在0.01~0.50 μg/g添加范围内的回收率为72.2%~106.5%,相对标准偏差为0.6%~6.4%,检出限为0.01~0.02 μg/g。     

Determination of Herbicide Residues in Garlic by GC–MS

A rapid multi-residue method has been developed for the determination of 16 herbicides in garlic. The analytical procedure is based on prior microwave heating prevention of the generation of sulfur-containing compounds. The garlic samples which had been pretreated were extracted with acetonitrile and cleaned up by solid-phase extraction. The herbicide residues were detected by gas chromatography–mass spectrometry with selected ion monitoring. The recoveries of 16 herbicides ranged from 69.0 to 105.4% with the relative standard deviations (RSD) below 10.1%. The limit of quantification (LOQ) ranged from 0.003 to 0.015 mg kg⁻¹.

     

Determination of Herbicide Residues in Garlic by GC–MS

A rapid multi-residue method has been developed for the determination of 16 herbicides in garlic. The analytical procedure is based on prior microwave heating prevention of the generation of sulfur-containing compounds. The garlic samples which had been pretreated were extracted with acetonitrile and cleaned up by solid-phase extraction. The herbicide residues were detected by gas chromatography–mass spectrometry with selected ion monitoring. The recoveries of 16 herbicides ranged from 69.0 to 105.4% with the relative standard deviations (RSD) below 10.1%. The limit of quantification (LOQ) ranged from 0.003 to 0.015 mg kg^?1.     

QuEChERS/超高效液相色谱-串联质谱法测定土壤中31种磺酰脲类除草剂残留

建立了一种基于QuEChERS前处理技术和超高效液相色谱-串联质谱(UHPLC-MS/MS)同时测定土壤中31种磺酰脲类除草剂残留的方法。通过对色谱条件、提取溶剂、净化剂等进行优化,确定以甲醇和0.1%甲酸+5 mmol/L乙酸铵为流动相,1%(体积分数)乙酸-乙腈为提取溶剂,C₁₈(25.00 mg/mL)为净化剂。31种磺酰脲类除草剂的线性关系良好,相关系数(r²)均不小于0.998 0,定量下限(S/N=10)为0.012～2.321μg/kg。3个加标水平(10、100、400μg/kg)下的平均回收率为71.8%～119%,相对标准偏差(RSD)为0.62%～13%。除烟嘧磺隆、三氟啶磺隆钠、玉嘧磺隆、啶嘧磺隆、氯吡嘧磺隆为中等强度基质效应外,其余待测物均表现为弱基质效应。该方法简便易操作,具有较好的灵敏度和准确度,适用于土壤中31种磺酰脲类除草剂残留的同时检测。     

磺酰脲类除草剂在水、土壤及小麦中残留分析的前处理方法研究

分别采用不同的前处理方法处理水、土壤和小麦样品。水样采用C18固相萃取小柱净化和富集;土壤样品以二氯甲烷为提取剂,超声波提取,液-液分配净化;小麦样品经二氯甲烷超声波提取,氟罗里硅土柱净化、富集。样品中磺酰脲除草剂甲磺隆、氯磺隆、苄嘧磺隆的残留量采用高效液相色谱-紫外检测器同时测定。三种磺酰脲除草剂在0.1～4.0mg·mL-1范围内线性良好,相关系数在0.9996～0.9997之间。水样、土壤样品和小麦样品的平均加标回收率分别为82.0%～107.0%、84.5%～100.6%、80.0%～98.5%,相对标准偏差在0.7%～11.2%之间。