大体积全自动固相萃取气相色谱–质谱法测定水中苯并芘

建立了全自动固相萃取–气相色谱–质谱联用测定水中苯并芘的方法。优化了全自动固相萃取条件,选择C8固相萃取柱萃取水样品中的苯并芘,样品中加入甲醇以增强苯并芘在萃取柱上的保留能力,采用正压大体积六通道同时进样,进样体积为1 000 m L,进样流量20 m L/min,使用二氯甲烷为洗脱溶剂,浓缩至0.5 m L。水中苯并芘的质量浓度在10~200μg/L范围内与其质谱响应值线性关系良好,相关系数为0.995,检出限为2 ng/L。在20~200μg/L加标水平上,苯并芘回收率为85.0%~94.5%,测定结果的相对标准偏差均小于6%(n=6)。该方法操作简单、测定结果准确,可用于水中苯并芘的测定。     

固相萃取–气相色谱法测定水中三卤甲烷

建立固相萃取–气相色谱法测定水中三卤甲烷的含量。考察了固相萃取柱、洗脱剂、氯化钠加入量和水样p H值对待测物萃取效果的影响。水样经C18固相萃取柱富集,乙酸乙酯和二氯甲烷洗脱,经气相色谱电子捕获检测器检测,三卤甲烷各组分分离良好。三卤甲烷的质量浓度在0.00~40.0μg/L范围内与对应的色谱峰面积均呈良好线性关系,线性相关系数大于0.999,三卤甲烷加标回收率为91.4%~104.0%,测定结果的相对标准偏差均小于1.5%(n=6)。该方法操作简便,准确度、精密度好,灵敏度高,检出限低,适用于水中三卤甲烷的测定。     

微波辅助萃取-气相色谱法测定茶叶中的有机磷农药

建立了微波辅助萃取–气相色谱法测定茶叶中甲胺磷、乐果、毒死蜱、水胺硫磷、三唑磷5种有机磷农药残留量的分析方法。样品用乙酸乙酯微波辅助提取,提取液经分散固相萃取法(DSPE)净化,用气相色谱配FPD检测器测定,外标法定量。结果表明农药混合标准溶液在0.01～0.5μg/mL范围内线性良好(r>0.999),方法的检出限为0.005～0.01 mg/L,在0.05,0.125,0.5μg/mL 3个水平添加平均回收率为63.3%～99.9%,测定结果的相对标准偏差为5.1%～8.2%(n=6)。该方法适合于茶叶中多种有机磷农药残留量的同时检测。     

固相萃取-气相色谱法测定饮用水中12种农药

提出了固相萃取-气相色谱法测定饮用水中12种农药残留量的方法。取水样250mL过固相萃取柱,用乙酸乙酯、正己烷各5mL洗脱,经无水硫酸钠脱水,采用DB-5MS毛细管色谱柱分离,电子捕获检测器检测。溴氢菊酯的线性范围为0.05~0.5mg·L-1,其他农药的线性范围均在0.01~0.1mg·L-1。溴氰菊酯的检出限为24.2ng·L-1,其他农药的检出限均低于10ng·L-1。12种农药的加标回收率在70.0%~110%之间,相对标准偏差(n=6)均小于10%。     

介孔氧化铝净化-气相色谱法同时测定蔬菜、水果及茶叶中16种有机磷农药残留

利用气相色谱检测技术,建立了能应用于白菜、生菜、南瓜、洋葱、番茄、白萝卜、苹果、梨及茶叶等不同基质中16种有机磷农药残留的检测方法。样品采用乙酸乙酯提取,经以合成的介孔氧化铝作吸附剂的固相萃取柱净化,DB-1701毛细管柱分离,气相色谱-火焰光度检测器检测。结果表明,蔬菜、水果及茶叶基质中16种有机磷农药在10~2000 μg/L范围内具有良好的线性关系（R²>0.997）;平均回收率为83.2%~103.8%,相对标准偏差为2.0%~9.9%。该方法灵敏度高、准确度高、重复性好,可适用于蔬菜、水果及茶叶基质中16种有机磷残留量的同时测定。     

固相萃取–气相色谱–质谱法测定地表水中的三氯苯

建立固相萃取–气相色谱–质谱联用法测定地表水中三氯苯的方法,对固相萃取柱、洗脱剂、甲醇用量进行优化试验。在200 m L水样中加入20 m L甲醇,采用C18固相萃取柱,以正己烷为洗脱溶剂萃取水中的三氯苯,用气相色谱–质谱法测定。结果表明,三氯苯的三种同分异构体分离良好,1,2,3-三氯苯、1,2,4-三氯苯、1,3,5-三氯苯的质量浓度在2.0~100μg/L范围内与其色谱峰面积均呈良好的线性,线性相关系数分别为0.999 1,0.999 4,0.999 2,检出限分别为0.004,0.005,0.005μg/L,加标回收率为90.3%~96.5%,测定结果的相对标准偏差均小于2%(n=7)。该方法操作简便、快速,定性定量准确,有机试剂用量少,适用于地表水中三氯苯的检测。     

在线固相萃取-超高效液相色谱-三重四极杆质谱法测定水源水和饮用水中107种典型农药及代谢产物

为进行我国水体中农药风险监测,针对水体中农药种类多、浓度低的特点,建立了在线固相萃取-超高效液相色谱-串联质谱法快速筛查和检测水源水及饮用水中107种典型农药及代谢产物(有机磷类、有机氮类、有机杂环类、氨基甲酸酯类、酰胺类、苯甲酰脲类、新烟碱类等)的方法。样品经0.22 μm孔径亲水性聚四氟乙烯滤膜过滤后,通过自动进样器取5 mL样品注入在线固相萃取系统,经X Bridge C₁₈在线固相萃取柱吸附后用纯水淋洗,以乙腈和0.1%甲酸水溶液为流动相对在线固相萃取柱梯度洗脱后再经ACQUITY HSS T₃色谱柱分离,采用电喷雾离子源正离子及负离子模式分析检测,外标法定量。以水源水及饮用水作为基质,对其准确度和精密度进行方法学验证,结果表明:107种农药及代谢产物在不同范围内线性关系良好(r²>0.995),方法检出限(LOD, S/N=3)为0.03~1.5 ng/L,定量限(LOQ, S/N=10)为0.1~5.0 ng/L。将目标分析物在1、20、50 ng/L水平下加标,水源水和饮用水中的加标回收率分别为60.6%~119.8%和61.2%~119.0%,相对标准偏差(RSD, n=6)分别为0.3%~18.6%和0.4%~17.1%。用该方法测定水源水和饮用水中的农药残留,结果显示,酰胺类、三嗪类除草剂、三唑类杀菌剂与烟碱类、氨基甲酸酯类杀虫剂有较高的检出率,其中水源水中检出含量为0.1~97.1 ng/L,饮用水中检出含量为0.1~93.6 ng/L。该方法适用于水源水和饮用水中107种典型农药及代谢产物的痕量分析测定,有效提高了水体中农药类物质的检测效率,实际应用价值较高。     

自制双层固相萃取柱在新会陈皮及其制品中11种有机磷农药测定中的应用

以自制改性多壁碳纳米管（MWNTs）和N-丙基乙二胺（PSA）填料分层填装的双层固相萃取柱为净化柱,建立了测定陈皮及其制品中11种有机磷农药残留的分析方法。样品经乙酸乙酯提取、离心后,固相萃取柱净化,净化液经Agilent RTS-1701毛细管柱分离,火焰光度检测器检测,外标法定量。考察了填料类型、填料用量、洗脱方式等因素对提取效率的影响。在优化条件下,11种有机磷农药检测的线性范围为0.020~1.0 mg/L,相关系数为0.9990~0.9998,检出限为3.5~9.6 μ g/kg。样品在10、25、100 μg/kg 3种水平下的加标回收率为50.8%~109%,相对标准偏差为2.7%~8.5%。该法准确度和灵敏度高、操作简单、快速,检出限能满足对有机磷农药残留的限量要求。自制固相萃取柱可降低成本,值得推广应用。     

顶空固相微萃取-气相色谱-质谱法同时测定饮用水源水中24种VOCs

建立了同时测定饮用水源水中24种挥发性有机物(VOCs)的顶空固相微萃取-气相色谱-质谱法.用75 μm CarboxenTM-Polydimethylsiloxane(CAR-PDMS)固相微萃取柱顶空萃取水样中的VOCs,VOCs用气相色谱-质谱联用仪检测,采用内标法定量.对萃取柱涂层、样品盐度、萃取温度和萃取时间等样品前处理条件进行了优化,VOCs的检出限在0.03～0.31 μg/L之间,线性相关系数r＞0.996(二氯甲烷和三氯甲烷除外).对饮用水源水实际水样0.50μg/L和1.00 μg/L两个加标浓度水平的回收率进行了测定,三氯甲烷回收率均值分别为104％和142％,其余VOCs回收率分别为90.0％～120％和88.0％～110％,除二氯甲烷和三氯甲烷外,其余VOCs测定结果的相对标准偏差均小于15.0％(n=6).该方法适用于饮用水源水中挥发性有机物的监测分析.     

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。     

固相萃取-GC-MS法测定水中四氯联苯

建立全自动固相萃取-气相色谱-质谱法检测水中微量四氯联苯的方法。采用全自动固相萃取装置配有C_(18)固相萃取盘富集浓缩水中四氯联苯后,用乙酸乙酯和二氯甲烷洗脱,以CD-5MS毛细管色谱柱分离,气相色谱质谱法测定水中四氯联苯的含量。对水样的洗脱剂、萃取流速、pH值、甲醇加入量等进行了优化试验,四氯联苯PCB52,PCB77,PCB81的质量浓度在5.00~50.0μg/L范围内与色谱峰面积呈良好的线性,检出限分别为0.002,0.003,0.002μg/L;加标回收率分别为90.9%,92.7%,95.4%;测定结果的相对标准偏差均小于3%(n=7)。该方法灵敏度高,适用于水样中痕量四氯联苯的监测。     

Rapid multiresidue screening method for organophosphate pesticides in vegetables

Summary A rapid and efficient multiresidue extraction procedure using ethyl acetate and sodium sulfate has been applied to the analysis of diazinon, methamidophos, chlorpyrifos, malathion, parathion, parathion-methyl, dimethoate and monocrotophos residues in many different kinds of vegetables. No cleanup step was required Concentrated extracts were analysed by gas chromatography with flame photometric detection in phosphorus mode. Recovery studies were performed in six kinds of matrices at two fortification levels. Recoveries were in the range 80–115%. The limit of quantification of the analytical method has been estimated as 0.01 ppm for diazinon, methamidophos and malathion, 0.03 ppm for chlorpyrifos, parathion, parathion-methyl and dimethoate and 0.1 ppm for monocrotophos. Experiments showed that potentially it should be possible to develop a rapid and universally applicable method for organophosphate pesticide residues in different matrices.     

Determination of benomyl, diphenyl, o-phenylphenol, thiabendazole, chlorpyrifos, methidathion, and methyl parathion in oranges by solid-phase extraction, liquid chromatography, and gas chromatography

A simple and rapid method was developed for determination of benomyl, diphenyl (DP), o-phenylphenol (OPP), thiabendazole (TBZ), chlorpyrifos, methidathion, and methyl parathion in whole oranges. These compounds were extracted from a mixture of samples and anhydrous sodium acetate with ethyl acetate. The ethyl acetate extract was concentrated and cleaned up by passing through tandem solid-phase extraction columns consisting of anion-exchange and primary/secondary amine bonded silica. The eluate was concentrated and volume was adjusted with methanol for subsequent liquid chromatography (LC) and gas chromatography (GC). Benomyl (as methyl-2-benzimidazole carbamate, MBC), DP, OPP, and TBZ residues were determined by LC with fluorescence detection. Recoveries at 3 fortified levels (0.1, 1, and 10 micrograms/g) ranged from 63.9 to 97.4%, with coefficients of variation (CVs) of 1.6 to 15.5%. Limits of detection (LODs) were 0.01 microgram/g for DP, OPP, TBZ and 0.05 microgram/g for benomyl. Chlorpyrifos, methidathion, and methyl parathion residues were determined by GC with flame photometric detection. Recoveries ranged from 90.4 to 97.0%, with CVs of 2.1 to 5.9%. LODs were 0.005 microgram/g for chlorpyrifos and methyl parathion, and 0.01 microgram/g for methidathion.     

Determination of rotenone residues in raw honey by solid-phase extraction and high-performance liquid chromatography

A method for determining residues of the insecticide rotenone in raw-honey by high-performance liquid chromatography (HPLC) is described. To extract the residues, organic solvents such as ethyl acetate, n-hexane/dichloromethane and solid-phase extraction with octadecylsilane cartridges or Florisil packed columns were tested. Determination was carried out by reversed-phase HPLC using acetonitrile-buffer phosphate (pH 7) (60:40, v/v) as mobile phase and detection at 210 nm. Although the data showed that the two extraction methods were able to isolate the pesticide residues, the extraction on octadecylsilane cartridges was preferred due to its simplicity and higher recovery. Recoveries depended strongly on the fortification level for the two extraction procedures. Practical determination limits of 0.015 mg/kg were obtained. In the analysis of honeys, from beehives treated with rotenone at therapeutical doses for 1 month, residual amounts below 0.2 mg/kg were found.     

气相色谱法测定生活饮用水中2-氯苯酚和2-甲苯酚

采用固相萃取(SPE)小柱固相萃取,建立了生活饮用水中2-氯苯酚和2-甲苯酚的气相色谱检测方法。用盐酸调节水样至p H 5.0,用SPE小柱固相萃取后以乙酸乙酯洗脱,以CD-5色谱柱进行分离,氢火焰离子化检测器检测2-氯苯酚和2-甲苯酚的含量。2-氯苯酚和2-甲苯酚的质量浓度在2.00~40.0μg/L范围内与色谱峰面积线性关系良好,检出限分别为0.03,0.04μg/L;加标回收率分别为87.2%~93.9%,89.0%~94.8%;测定结果的相对标准偏差均小于2%(n=7)。该方法具有检出限低、操作简便等优点,适用于生活饮用水中2-氯苯酚和2-甲苯酚的监测分析。     

固相萃取–毛细管气相色谱法同时测定水体中8种有机磷类农药残留

建立固相萃取–毛细管气相色谱法同时测定水体中敌敌畏、乙酰甲胺磷、治螟磷、乐果、甲基对硫磷、马拉硫磷、杀螟硫磷和水胺硫磷8种有机磷类农药残留。样品经OASIS HLB固相萃取柱富集,丙酮洗脱,用毛细管气相色谱(FPD)法进行定量分析。8种有机磷类农残留的质量浓度在0.05~4.0μg/m L范围内与色谱峰面积线性关系良好,相关系数均大于0.998,方法检出限为0.004~0.01μg/m L。测定结果的相对偏差为2.6%~4.5%(n=6),加标回收率为81.6%~106.2%。该方法操作简单、灵敏度高,可用于检测水体中的8种有机磷类农药残留。     

超高效液相色谱法测定甘蔗和土壤中敌草隆残留

建立了一种测定甘蔗和土壤中敌草隆农药残留的超高效液相色谱(UPLC)方法.样品经水和甲醇提取,二氯甲烷液-液分配后,过中性氧化铝柱纯化,用石油醚:乙酸乙酯的混合液(体积比85:15)淋洗和洗脱,洗脱液经减压浓缩后用5 mL乙腈定容.采用UPLC分离,紫外检测器检测,外标法定量.敌草隆在0.02～5.0 mg/L范围线性...     

Extraction of pesticides from aqueous samples: A comparative study

Three different extraction procedures for eight pesticides (chlorfenvinphos, diazinon, ethyl parathion, ethiofencarb, fenitrothion, malathion, metalaxyl, pirimicarb) in water samples are compared. The extraction procedures are: liquid-liquid extraction (LLE), solid-phase extraction (SPE) and microextraction (ME). For each procedure the most suitable conditions were obtained experimentally, with special remarks on ME, in which the effects of different mixtures of Kaltron with other solvents were tested. A preconcentration factor (PF) was used to rank the methods; the best results were observed for ME, (PF 15–45, whereas PF < 10 for SPE, and PF 13 for LLE). In all cases, the determination was performed by gas chromatography, using a nitrogen phosphorus detector and the internal standard method (methyl parathion) as the quantification procedure.     

顶空采样-毛细管气相色谱法分析格列美脲原料药中的溶剂残留

建立了顶空采样-毛细管气相色谱检测格列美脲原料药中溶剂残留的分析方法。对产自国内8个生产厂家的格列美脲样品中有机溶剂的残留状况进行了系统评价,结合药品生产工艺信息,确定了丙酮、乙酸乙酯、甲醇、异丙醇、乙醇、氯仿、甲苯、1,4-二氧六环、吡啶、氯苯、乙醚、二氯甲烷、正己烷和苯等14种有机溶剂为残留检测对象。根据被测组分在色谱柱上的保留性质将其分为两类,以实现基线分离。用Supelco-Wax极性色谱柱,以乙腈为内标物,分离检测了丙酮、乙酸乙酯、甲醇、异丙醇、乙醇、氯仿、甲苯、1,4-二氧六环、吡啶和氯苯的残留量;用Supelco OVI-G43弱极性色谱柱,以丁酮为内标,分离检测了乙醚、二氯甲烷、正己烷和苯的残留量。14种残留组分在各自的浓度范围内呈良好的线性关系(r=0.99167～0.99997,n=8),最低检出限范围为0.2～13.5 μg/g;14种残留组分检测的日间重复性(以相对标准偏差(RSD)计)为0.6%～9.2%(n=3),3种加标浓度的平均添加回收率为86.3%～104.1%(RSD为0.2%～5.3%,n=16)。实验结果表明,该方法简单、灵敏、可靠,适用于格列美脲中残留溶剂的分析确证。     

Contributions to the ethyl acetate application in residue analysis

Summary For the determination of pesticide residues 10 fruit and vegetable samples and 2 wheat samples with unknown spray history were extracted by the micro on-line extraction technique using the binary solvent system water + ethyl acetate as the extracting agent. The results of this proposed micro extraction were compared with already tested methods and it was found that the micro ethyl acetate method was equally effective. The reduction of solvents and chemical waste by miniaturization of analytical procedures is an important step for environmental protection.