加热处理-气相色谱法测定韭菜中有机磷农药残留量

建立了GC-FPD测定韭菜中7种有机磷农药残留量的方法。未经过处理的韭菜本底色谱图杂峰对韭菜中有机磷农药残留量的测定有影响;采用加热处理样品3min的方法,可有效去除干扰物,使韭菜本底色谱图杂峰变小。经过加热处理后的韭菜本底杂峰对测定韭菜中7种有机磷农药残留量基本没有影响。方法回收率87．12％～110．9％,RSD 1．4％～8．7％,检出限0．005～0．010mg／kg。     

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。     

Pyraflufen-ethyl residues in soil by solid phase extraction and high-performance liquid chromatography with UV detection.

Solid-phase extraction (SPE) procedure for cleanup followed by HPLC-UV method has been investigated for the determination of pyraflufen-ethyl residues in soil. The pesticide is extracted from the sample with acetone-water (80:20, v/v) and the extract is loaded onto an octadecyl (C(18)) column. The pesticide is eluted with acetonitrile and determined by HPLC with a UV detector. Using an acetone-water extraction followed by a C(18) cleanup, this method is characterized by recovery >90.1%, precision <5.8% RSD and sensitivity of 0.01 mg/kg. The proposed method has been successfully employed for the determination of the degradation dynamics of pyraflufen-ethyl in four agricultural soil samples under laboratory conditions.     

凝胶净化-毛细管气相法测定黄瓜、番茄和青椒中15种有机磷农药

 建立了凝胶柱净化蔬菜样本,毛细管气相 火焰光度检测器测定15种有机磷农药的方法。用环己烷 乙酸乙酯(体积比为1∶1)淋洗液以1mL/min的流量洗脱凝胶柱(10mmi d ×200mm,SX 3),分别用气相检测各段流出液中农药的含量,得到了15种有机磷农药的凝胶流出曲线。采用该方法检测,15种有机磷农药在黄瓜、番茄和青椒中的最小检出质量比均低于5×10-3mg/kg,在蔬菜中不同添加浓度的平均回收率为77 8%～106%,相对标准偏差(RSD)为0 10%～16 6%,其准确度和精密度均达到了农药残留分析的要求。     

气相色谱法测定茶叶中多种有机磷农药残留量

 采用微量化学法和全自动固相萃取技术 ,建立了气相色谱法同时测定茶叶中 14种有机磷农药残留量的方法 ,并对样品的前处理作了一定的探讨。结果表明 ,采用程序升温 ,所测定的 14种有机磷农药在SPBTM 170 1石英毛细管柱上得到了很好的分离 ,且方法快速、灵敏 ,完全符合实际应用需要。     

高效液相色谱-飞行时间质谱法筛查大豆中残留的多种除草剂和杀虫剂

应用高效液相色谱-飞行时间质谱建立了筛查大豆中77种除草剂和杀虫剂残留的新方法。在不同添加浓度下获得了精确的分子离子质量,质量偏差的绝对值低于3×10-6。所有除草剂和杀虫剂在0.03～1.00 mg/kg范围内线性关系良好（r≥0.99）。除一些除草剂外,多数除草剂和杀虫剂的添加回收率为60%～120%,在大豆基质中的检测限为0.003～0.026 mg/kg。该方法适合于大豆中多种除草剂和杀虫剂残留的分析检测需要,方法简便、高效、准确。     

高效液相色谱法快速测定板栗中戊唑醇的残留量

建立了反相液相色谱法测定板栗中戊唑醇残留量的分析方法。以甲醇作为提取液,经分散离心后,上清液过0.22μm滤膜,HPLC分析,采用外标法定量。结果表明:戊唑醇浓度在0.1～10.0 mg/L范围内与色谱峰面积呈线性关系,相关系数r=0.9979。板栗中戊唑醇加标回收率在79.8%～93.9%之间,测定结果的相对标准偏差为2.3%～8.9%(n=5),检出限为0.079 mg/kg。该方法满足板栗进出口检测要求。     

Confirmation of synthetic glucocorticoids with liquid chromatography/mass spectrometry: organization and results of an international interlaboratory comparison test

Within the framework of a European Union (EU) research project entitled "Food Safety Screening: Synthetic Glucocorticoids (QLK1-1999-00122)," an international interlaboratory ring test was organized to compare and evaluate different liquid chromatography/mass spectrometry (LC/MS) confirmatory methods that are applied in European monitoring programs for detecting the use of synthetic glucocorticoids. Liver and urine samples of bovines treated with synthetic glucocorticoids were collected and sent to the participants of the study for analysis. Participants received 3 liver and 3 urine samples and were free to use either their own LC/MS method or an LC/MS-based method developed during the EU research project. The residue concentrations in the samples were calculated as the mean of the concentrations reported by each laboratory. The mean dexamethasone concentration of liver sample L1 was calculated as 2.27 microg/kg [relative standard deviation (RSD) 43%, n = 9], which exceeds the maximum residue level (MRL) of 2 microg/kg. Three of the 9 laboratories (33%) reported concentration levels less than 2 microg/kg, resulting in obviously false compliant results. The overall mean concentration of flumethasone in liver sample L2 was calculated as 3.27 microg/kg (RSD 33%, n = 8). Applying a comparable limit for flumethasone of 2 microg/kg, 8 of the 9 laboratories would have obtained a correct noncompliant result. As for the blank liver sample, 1 participant found a false noncompliant result. The urine sample U1 contained prednisolone residues at a mean concentration of 1.58 microg/kg (RSD 43%, n = 9). Four out of 9 results were less than a theoretical minimum required performance level (MRPL) of 2 microg/kg. The calculated concentration of dexamethasone in urine sample U3 was 5.21 microg/kg (RSD 62%, n = 9). One of the 9 results was lower than 2 microg/kg. Urine sample U2 was correctly reported as blank by all participants.     

QuEChERS-UPLC-MS/MS法检测苹果中5种农药残留

建立了QuEChERS-超高效液相色谱-串联质谱(QuEChERS-UPLC-MS/MS)检测苹果中5种农药残留的分析方法.样品采用QuEChERS进行前处理,乙腈提取,经PSA、纳米氧化锆(Nano-ZrO2)和多壁碳纳米管(MWCNTs)组合净化,结合UPLC-MS/MS检测,外标法定量.结果表明,在0.005～0...     

微波辅助提取-气相色谱法同时测定中草药中有机磷和氨基甲酸酯农药残留

建立了中草药中有机磷和氨基甲酸酯类农药同时检测的气相色谱分析新方法.中药材试样依据正交实验的优化条件,用正己烷-丙酮(1∶4,V∶V)混合提取剂进行微波辅助提取,经弗罗里硅土和中性氧化铝混合层析柱净化后,采用HP-5毛细管柱分离,氮磷检测器同时检测中草药中15种有机磷和6种氨基甲酸酯类农药残留量.21种农药在0.01～1.0 mg/L的浓度范围内线性良好,线性相关系数为0.9950～1.000,检出限为0.002～0.01 mg/L.在0.05、0.2、0.5 mg/kg三个添加水平的平均回收率分别为75.11%～128.57%、75.85%～120.71%和76.43%～117.25%,相对标准偏差分别为 3.10%～10.58%、5.27%～9.94%和4.03%～9.03%.方法用于中草药中有机磷和氨基甲酸酯类农药残留的同时检测,结果良好.     

气相-质谱法测定粮谷中恶草酮的残留量

 应用微量化学法和固相萃取技术 ,建立了粮谷中恶草酮残留量的气相 质谱 (GC MS)测定方法。用苯 正己烷 (体积比为 1∶1)萃取 ,中性氧化铝小柱净化。净化液用GC MS测定 ,采用外标法定量。恶草酮在大米中的回收率为 90 4%～ 115 .7% ,RSD为 2 %～ 6 % ,在玉米中的回收率为 81 3%～ 10 9 7% ,RSD为 4%～ 9% ,最低定量检出限为 0 0 0 5mg/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。     

Simultaneous Determination of Multi-Class Pesticide Residues and PAHs in Plant Material and Soil Samples Using the Optimized QuEChERS Method and Tandem Mass Spectrometry Analysis

New analytical approaches to the simultaneous identification and quantification of 94 pesticides and 13 polycyclic aromatic hydrocarbons (PAHs) in five representative matrices (pepper, apple, lettuce, wheat, and soil) were developed. The analyses were based on gas chromatography coupled with triple quadrupole tandem mass spectrometry (GC-MS/MS). The procedure was optimized by changing the solvent used during the extraction, from acetonitrile to the acetone: n-hexane mixture at a volume ratio of 1:4 (v/v), as well as the use of a reduced amount of water during the extraction of compounds from cereals. An additional modification was the use of florisil instead of GCB in the sample cleanup step. A full method validation study was performed, at two concentration levels (LOQ and 1000 × LOQ), which showed satisfactory results for all analytes from the PAHs group, with recoveries ranging from 70.7–115.1%, and an average RSD of 3.9%. Linearity was tested in the range of 0.001–1.000 mg/kg and showed coefficients of determination (R²) ≥ 0.99 for all PAHs. Satisfactory recovery and precision parameters (LOQ and 100 × LOQ) were achieved for almost all analytes from the pesticide group in the range of 70.1–119.3% with the mean RSD equal to 5.9%. The observed linearity for all analytes in the concentration range of 0.005–1.44 mg/kg was R² ≥ 0.99, with the exception of famoxadone, chizalofop-p-ethyl, prothioconazole, spirodiclofen, tefluthrin, and zoxamid. The extended uncertainties were estimated, using a top-down approach of 9.9% (average) and 15.3% (average) for PAHs and pesticides samples, respectively (the coverage factor k = 2, the 95% confidence level). Ultimately, the method was successfully applied to determine pesticide residues in commercial samples of fruit, vegetables and grain, and soil samples for PAHs, which were collected from selected places in the Podkarpacie region. A total of 38 real samples were tested, in which 10 pesticides and 13 PAHs were determined. Proposed changes allow us to shorten the sample preparation time (by 20%) and to reduce the consumption of organic solvents (by 17%). The use of florisil for sample cleanup, instead of GCB, improves the recovery of compounds with flat particles.     

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...     

气相色谱法测定坚果中8种拟除虫菊酯农药残留

建立了东盟进口坚果夏威夷果、开心果、杏仁中8种拟除虫菊酯农药残留的检测方法。样品采用乙腈作萃取溶剂超声波提取,经中性氧化铝串联弗罗里硅土小柱净化,组分经不同极性的两根毛细管柱进行分离,采用气相色谱法以ECD检测器检测坚果中8种拟除虫菊酯农药。该方法在0.01~1.0μg/m L浓度范围内具有良好的线性关系,相关系数为0.999 2~0.999 9;在农药添加浓度为10,20,50μg/kg时,回收率为71%~115%,相对标准偏差为4.5%~9.8%,检出限(LOD,S/N=3)为0.014~0.28μg/kg,定量下限(LOQ,S/N=10)为0.047~0.94μg/kg。该方法分离效果好,准确可靠,回收率高,方便快速,可用于坚果中农药残留的日常检测。     

荧光法快速检测有机磷农药残留总量

在pH4.60的B-R缓冲溶液中,中性红(NR)与一定浓度的十二烷基苯磺酸钠(SDBS)发生荧光增强反应,在该体系中加入有机磷农药后,在激发波长560 nm,发射波长604 nm处体系的荧光强度明显降低,且降低程度与有机磷农药的加入量呈良好的线性关系,其线性范围和检出限分别为0.024~0.40 mg/L,0.014 mg/L。据此建立了测定有机磷农药残留总量的新方法。方法已用于面粉和土壤中有机磷农药残留总量的检测,回收率在92.0%~100.5%之间,RSD在1.1~1.9%之间。     

坚果及其制品中匹克司残留量气相色谱测定法

确立了坚果及其制品中匹克司残留量的气相色谱测定方法试样采用甲醇提取，经ＰＴ－硅镁柱净化，ＧＣ－ＥＣＤ测定，方法简便，快速灵敏，检出限０．０２＊１０＾－３ｇ／ｋｇ，添加回收率８７．４％－９３．２％，相对标准偏差４．４％－６．８８％．。     

固相萃取-高效液相色谱法同时测定苹果中残留的克菌丹和灭菌丹

采用硅镁吸附剂和硅胶作吸附剂,建立了固相萃取-高效液相色谱法同时测定苹果中残留的克菌丹和灭菌丹的分析方法。研究了甲醇-乙腈-水(含0.1 mmol/L乙酸-乙酸钠缓冲溶液（pH 3.80）)三元体系下克菌丹和灭菌丹的最佳分离条件,在波长210 nm下检测,克菌丹和灭菌丹的线性范围为0.40～8.00 mg/kg,线性相关系数均大于0.9999;最低检出限克菌丹为0.27 mg/kg、灭菌丹为0.20 mg/kg;保留时间的相对标准偏差（RSD）≤0.60%。苹果样品中3个添加水平的平均加标回收率为克菌丹69.3%～106%,RSD为3.7%～4.7%;灭菌丹101%～108%,RSD为1.3%～5.4%。     

凝胶渗透色谱-气相色谱质谱法测定：花生中6种除草剂农药残留

建立了凝胶渗透色谱一气相色谱质谱（GPC～GC=MS）法测定花生中6种除草剂（氟乐灵、异恶草酮、甲草胺、二甲戊乐灵、乙氧氟草醚、喹禾灵）农药残留的方法。样品经乙腈提取,氨基固相萃取柱和凝胶渗透色谱净化,在选择离子扫描（SIM）模式下进行气相色谱质谱法测定,外标法定量。6种除草剂浓度在0．02-1．00mg／L范围内与色谱峰面积呈良好的线性,线性相关系数为O．9949～0．9998,添加回收率为77．8％-101．6％,测定结果的相对标准偏差为4．4％～11．4％（月=5）,方法的检出限为0．1～1．3μg／kg。     

超高效液相色谱–串联质谱法测定生活饮用水中10种农药残留

采用超高效液相色谱–串联质谱法测定生活饮用水中10种农药残留。水样直接进样,选用Waters ACQUITY UPLC~BEH C_(18)柱分离,以乙腈–0.1%甲酸溶液为流动相进行梯度洗脱,质谱选用多反应监测模式分析,10种农药的质量浓度在0.5~50μg/L范围内与色谱峰面积呈线性相关,检出限(3S/N)在0.03~0.50μg/L之间,测定值的相对标准偏差在1.14%~9.91%之间,加标回收率在91.6%~107.1%之间。该法简便准确,适用于生活饮用水中农药残留的检测。     

固相萃取-气相色谱法测定茶叶中多种有机磷农药

建立了固相萃取-气相色谱法同时测定茶叶中16种有机磷农药残留的方法.样品用丙酮超声提取后,经自制的N-丙基乙二胺(PSA)/活性炭固相萃取柱净化,以混合溶剂乙腈/甲苯(V(乙腈)∶V(甲苯)=1∶3)洗脱,采用气相色谱-氮磷检测器(GC-NPD)测定.方法的回收率在62.8%～109.1%之间,相对标准偏差小于14.7%1,6种有机磷农药的检出限在0.01～0.16 mg/kg之间.方法快速简便、经济实用。