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1.
The copper(II) isonicotinate (Cu(4-C5H4N-COO)2(H2O)4) coordination polymer was prepared, characterized and explored as sorbent for flow injection solid-phase extraction on-line coupled with high-performance liquid chromatography (HPLC) for determination of trace polycyclic aromatic hydrocarbons (PAHs) in environmental matrices. Naphthalene, phenanthrene, anthracene, fluoranthene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene and benzo(ghi)perylene with various shape, size and hydrophobicity were used as model analytes. The porosity of the coordination polymer allows these guest PAHs molecules to diffuse into the buck structure, and the shape and size of the pores lead to shape- and size-selectivity over the guests. The precolumn packed with the coordination polymer was shown to be promising for solid-phase extraction of PAHs in environmental samples with subsequent HPLC separation and UV detection. With extraction of 50 ml of sample solution, the enhancement factors for the PAHs studied ranged from 200 to 2337, depending on the shape, size and hydrophobic property of the PAHs. The detection limits (S/N = 3) of 2-14 ng l(-1) and the sample throughput of 3 samples h(-1) were obtained. The developed method was applied to the determination of trace PAHs in a certified reference material (coal fly ash) and local water samples.  相似文献   

2.
Multiwalled carbon nanotubes (MWCNTs) were used as a novel kind of solid-phase extraction adsorbents in this work as well as an analytical method based on MWCNTs solid-phase extraction (SPE) combined with high-performance liquid chromatography (HPLC) was established for the determination of polycyclic aromatic hydrocarbons (PAHs), some of which belong to typical persistent organic pollutants (POPs) owing to their carcinogenicity and endocrine disrupting activity. Several conditions that probably affected the extraction efficiency including the eluent volume, sample flow rate, sample pH and the sample volume were optimized in detail. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method, and the method was applied to the determination of PAHs in environmental water samples such as river water sample, tap water sample and wastewater sample from the constructed wetland effluent. The experimental results indicated that there were excellent linear relationship between peak area and the concentration of PAHs over the range of 0.04-100 microg L(-1), and the precisions (RSD) were 1.7-4.8% under the optimal conditions. The detection limits of proposed method for the studied PAHs were 0.005-0.058 microg L(-1) (S/N=3). The recoveries of PAHs spiked in environmental water samples ranged from 78.7 to 118.1%. It was concluded that MWCNTs packed cartridge coupled with HPLC was an excellent alternative for the routine analysis of PAHs at trace level.  相似文献   

3.
Ge D  Lee HK 《Journal of chromatography. A》2011,1218(47):8490-8495
Zeolite imidazolate framework 8 (ZIF-8) has permanent porosity, high surface area, hydrophobic property, open metal sites and remarkable water stability. These novel properties characterize the material as being different from other moisture sensitive metal-organic frameworks and endow ZIF-8 with the potential to extract trace analytes from environmental water samples. In the present study, ZIF-8 was synthesized and used as a sorbent for micro-solid-phase extraction of 6 polycyclic aromatic hydrocarbons (PAHs) from environmental water samples for the first time. Parameters influencing the extraction efficiency such as desorption time, extraction time, desorption solvent and salt concentration were investigated. Environmental water samples collected from a local lake were processed using this novel μ-SPE procedure. ZIF-8 proved to be a very efficient extraction sorbent for the extraction of trace analytes from water samples. The limits of detection from gas chromatography-mass spectrometric analysis of PAHs were 0.002-0.012 ng/ml. The linear ranges were 0.1-50 or 0.5-50 ng/ml. The relative standard deviations for five replicates of the extractions were in the range of 2.1-8.5%.  相似文献   

4.
The determination of polycyclic aromatic hydrocarbons (PAHs) using high-performance liquid chromatography (HPLC) with UV and fluorescence detection has been well established. Although most of the PAHs can be detected by these methods, some environmentally important polyaromatic compounds, such as acenaphthylene, do not show fluorescence and can only be determined by UV detection at higher concentrations. A sensitive and selective determination of acenaphthylene, acenaphthene and the six PAHs listed in the TVO, the German drinking water standard, is also possible by amperometric detection following HPLC separation. The method was applied to the determination of PAHs in different water samples after solid-phase extraction (SPE). The efficiency of the amperometric determination was found to be superior to UV detection (λ = 300 nm).  相似文献   

5.
A new cost-effective sorbent, multiwalled carbon nanotubes/poly (vinyl alcohol) cryogel composite (MWCNTs/PVA), was prepared under frozen conditions for the extraction and preconcentration of trace polycyclic aromatic hydrocarbons (PAHs) in water samples. This was followed by high performance liquid chromatography (HPLC) with fluorescence detection. The proposed method provided a high enrichment factor with an extremely high extraction efficiency (89–98%) of three spiked levels of three standard PAHs with relative standard deviations of less than 8%. The low detection limits of the method were 5, 8 and 5 ng L− 1 for benzo(a)anthracene, benzo(b)fluoranthene and benzo(a)pyrene, respectively. This method was successfully applied for the determination of the three PAHs in real water samples where they were found in the range of 7 to 22 ng L− 1. The major advantages of MWCNTs/PVA over the commercial C18 is that it can be operated at a higher loading flow rate without sorbent clogging and requires a shorter time for completion without any loss of extraction efficiency.  相似文献   

6.
This study describes the determination of polycyclic aromatic hydrocarbons (PAHs) in water using high-performance liquid chromatography (HPLC) coupled with fluorescence detection (FLD). Because individual PAHs are generally present in water only at trace levels, a sensitive and accurate determination technique is essential. The separation and detection of five PAHs were run completely within 25 min by the HPLC/FLD system with an analytical C18 column, a fluorescence detection, and acetonitrile-water gradient elution. Calibration graphs were linear with very good correlation coefficients (r > 0.9998), and the detection limits were in the range of 2-6 ng/l for five PAHs. Solid phase microextraction (SPME) was performed for sample pretreatment prior to HPLC-FLD determination, and the governing parameters were investigated. Compared to conventional methods, SPME has high recovery, saves considerable time, and reduces solvents waste. The extraction efficiencies of five PAHs were above 88% and the extraction times were 35 min in one pretreatment procedure. One particular discovery is that 1.5 M sodium monochloroactate (ClCH2COONa) can improve the extraction yield of PAH compounds more than other inorganic salts. The SPME-HPLC-FLD technique provides a relatively simple, convenient, practical procedure, which was here successfully applied to determine five PAHs in water from authentic water samples.  相似文献   

7.
An on-line solid-phase extraction (SPE) protocol using the cigarette filter as sorbent coupled with high-performance liquid chromatography (HPLC) was developed for simultaneous determination of trace naphthalene (NAPH), phenanthrene (PHEN), anthracene (ANT), fluoranthene (FLU), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), and benzo(ghi)perylene (BghiP) in water samples. To on-line interface solid-phase extraction to HPLC, a preconcentration column packed with the cigarette filter was used to replace a conventional sample loop on the injector valve of the HPLC for on-line solid-phase extraction. The sample solution was loaded and the analytes were then preconcentrated onto the preconcentration column. The collected analytes were subsequently eluted with a mobile phase of methanol-water (95:5). HPLC with a photodiode array detector was used for their separation and detection. The detection limits (S/N = 3) for preconcentrating 42 mL of sample solution ranged from 0.9 to 58.6 ng L(-1) at a sample throughput of 2 samples h(-1). The enhancement factors were in the range of 409-1710. The developed method was applied to the determination of trace NAPH, PHEN, ANT, FLU, BbF, BkF, BaP and BghiP in local river water samples. The recoveries of PAHs spiked in real water samples ranged from 87 to 115%. The precisions for nine replicate measurements of a standard mixture (NAPH: 4.0 microg L(-1), PHEN: 0.40 microg L(-1), ANT: 0.40 microg L(-1), FLU: 2.0 microg L(-1), BbF: 1.6 microg L(-1), BkF: 2.0 microg L(-1), BaP: 2.0 microg L(-1), BghiP: 1.7 microg L(-1)) were in the range of 1.2-5.1%.  相似文献   

8.
张文敏  李青青  方敏  张兰 《色谱》2022,40(11):1022-1030
环境样品中多环芳烃(PAHs)含量较低且样品基质复杂,直接利用仪器进行含量测定比较困难,因此在仪器分析之前需要对环境样品进行必要的前处理。大多数前处理技术的萃取效率取决于萃取材料的特性。目前,金属有机骨架材料(MOFs)作为一种由金属离子与有机配体自组装而成的多孔材料,已经被用作固相微萃取(SPME)的涂层材料应用于PAHs的萃取,但是这些MOFs涂层材料由于目标物较难达到其深层的吸附位点,使得萃取过程往往需要较长的平衡时间;此外,大多数MOFs由单金属离子配位构成,能够提供的开放金属活性位点种类比较单一,较难获得最佳的萃取性能。这些问题在一定程度上限制了MOFs材料在SPME领域的应用。该研究制备了一种中空结构的双金属有机骨架材料(H-BiMOF),并将其作为SPME的涂层材料,用于萃取环境样品中痕量的PAHs。由于中空的结构和双金属的组成,H-BiMOF涂层材料拥有比表面积利用率高、传质距离短等优点,可以使萃取过程快速地达到平衡。同时,双金属的引入提供了种类丰富的金属活性位点,提高了对PAHs这类富电子云目标物的萃取效率。与气相色谱-串联质谱(GC-MS/MS)相结合,建立了一种用于环境水样中PAHs分析的新方法。所建立的分析方法具有检出限低(0.01~0.08 ng/L)、线性范围宽(0.03~500.0 ng/L)、重复性良好(相对标准偏差≤9.8%, n=5)等优点,并成功地用于实际湖水样品中7种PAHs的检测。实验结果表明,所建立的分析方法适用于环境样品中PAHs的分析与监测。  相似文献   

9.
A simple, rapid and efficient method, ionic liquid based dispersive liquid–liquid microextraction (IL-DLLME), has been developed for the first time for the determination of 18 polycyclic aromatic hydrocarbons (PAHs) in water samples. The chemical affinity between the ionic liquid (1-octyl-3-methylimidazolium hexafluorophosphate) and the analytes permits the extraction of the PAHs from the sample matrix also allowing their preconcentration. Thus, this technique combines extraction and concentration of the analytes into one step and avoids using toxic chlorinated solvents. The factors affecting the extraction efficiency, such as the type and volume of ionic liquid, type and volume of disperser solvent, extraction time, dispersion stage, centrifuging time and ionic strength, were optimised. Analysis of extracts was performed by high performance liquid chromatography (HPLC) coupled with fluorescence detection (Flu). The optimised method exhibited a good precision level with relative standard deviation values between 1.2% and 5.7%. Quantification limits obtained for all of these considered compounds (between 0.1 and 7 ng L−1) were well below the limits recommended in the EU. The extraction yields for the different compounds obtained by IL-DLLME, ranged from 90.3% to 103.8%. Furthermore, high enrichment factors (301–346) were also achieved. The extraction efficiency of the optimised method is compared with that achieved by liquid–liquid extraction. Finally, the proposed method was successfully applied to the analysis of PAHs in real water samples (tap, bottled, fountain, well, river, rainwater, treated and raw wastewater).  相似文献   

10.
刘颖  陈玲  唐银健  黄清辉  赵建夫 《色谱》2007,25(3):356-361
建立了高效液相色谱-二极管阵列检测器(PDA)测定上海市黄浦江表层沉积物中16种多环芳烃(PAHs)的方法。在保留时间定性分析的基础上,利用PDA获取的紫外扫描光谱图对目标组分进行了准确的定性,并通过异构体紫外光谱图中特征峰的差异有效地识别了样品中的4种异构体,即苯并[b]荧蒽、 苯并[k]荧蒽、 苯并[a]芘和苯并[e]芘。通过检测波长的优化,减少了干扰物的影响,提高了检测灵敏度;针对分离度较差的两种目标组分(苯并[b]荧蒽和苯并[k]荧蒽)的定量进行了分析讨论。该方法对16种PAHs的检出限(以干基计)介于1.1~18.3 ng/g之间,具有较高的方法灵敏度。黄浦江表层沉积物测定结果表明,除二氢苊外的15种PAHs都被检出,含量为10.1~253.0 ng/g。  相似文献   

11.
刘程  陈蕾  叶子雯  黄晓佳 《色谱》2019,37(8):918-923
采用自制的聚离子液体功能化磁性材料有效富集有机紫外防晒剂,并与高效液相色谱-二极管阵列检测器(HPLC-DAD)联用,建立了环境水样中痕量有机紫外防晒剂的检测方法。研究系统考察了解吸溶剂、吸附和解吸时间、样品pH值、离子强度等因素对萃取性能的影响。在最佳萃取条件下,水杨酸辛酯的线性范围为0.5~200.0 μg/L,其他有机紫外防晒剂的线性范围为0.2~200.0 μg/L;6种目标物的检出限(LOD,S/N=3)和定量限(LOQ,S/N=10)分别为0.009~0.13 μg/L和0.031~0.43 μg/L。所建方法成功用于实际环境水样中有机紫外防晒剂的测定,不同加标水平下目标物的加标回收率为71.4%~120%,相对标准偏差均低于10%。研究表明,所建方法具有操作简便、萃取速度快、灵敏度高和环境友好等特点,可用于环境水样中有机紫外防晒剂的检测。  相似文献   

12.
Guo L  Lee HK 《Journal of chromatography. A》2011,1218(52):9321-9327
Micro-solid-phase extraction (μ-SPE) was developed for the determination of trace level of 16 United States Environmental Protection Agency priority polycyclic aromatic hydrocarbons (PAHs) in river water samples with gas chromatography-mass spectrometry (GC-MS). In the μ-SPE device, multiwalled carbon nanotubes was employed as sorbent and was packed inside an porous polypropylene membrane "envelope" whose edges were heat-sealed to secure the contents. The μ-SPE device was placed in a stirred sample solution to extract the analytes. The porous polypropylene membrane envelope in μ-SPE device acts as a filter to exclude potential interferences, such as eliminating or reducing the influence of particles that are bigger than the pore size. After extraction, analyte desorption was carried out with a suitable organic solvent under ultrasonication. Important extraction parameters were optimized in detail, including the selection and amount of sorbent materials, the extraction temperature and extraction time, desorption solvent and desorption time, amount of organic modifier, agitation speed and sample ionic strength. Under the developed extraction conditions, the proposed method provided good linearity in the range of 0.1-50 μg/L, low limits of detection (4.2-46.5 ng/L), and good repeatability of the extractions (relative standard deviations, <12%, n=5). The developed μ-SPE method was successfully applied to the extraction of PAHs in river water samples. The μ-SPE method was demonstrated to be a fast and efficient method for the determination of PAHs from environmental water samples.  相似文献   

13.
Xie SM  Zhang M  Wang ZY  Yuan LM 《The Analyst》2011,136(19):3988-3996
Solid-phase extraction (SPE) is one of the most important techniques for sample preparation, purification, concentration and cleanup. Membranes made from synthetic organic polymers, cellulose, or glass fibers are used for sample pretreatment. In this work, we report that a porous metal membrane, the metal filter in HPLC, was used as a novel kind of solid-phase extraction adsorbent material. To evaluate the performance of the porous metal membrane for the SPE, naphthalene, fluorene, anthracene, phenanthrene, fluoranthene, pyrene, chrysene, perylene and benzo(a)pyrene were selected as analytes. Several parameters that affected the extraction efficiency such as the extraction time, the concentration of NaCl, the extraction temperature and the agitation speed were optimized. The experimental result indicates that the porous metal membrane possesses high adsorption ability to the tested polycyclic aromatic hydrocarbons (PAHs). Under the optimum conditions, the detection limits of the developed method were in the range of 0.03-0.082 μg L(-1) (S/N = 5), and excellent linear correlations between peak area and concentration of PAHs were found over the range of 0.1-60 μg L(-1). The precisions (RSD) for five replicate extractions of the PAHs from sample solutions were in the range of 2.6-5.0%. The recoveries of the PAHs from tap water and river water samples spiked with 9 PAHs (20 μg L(-1) of each individual PAH) ranged from 83.0% to 112.5%. The porous metal membrane is durable, simple, inexpensive, reproducible and has a high adsorption ability for use in SPE of PAHs.  相似文献   

14.
The carbon coated Fe3O4 nanoparticles (Fe3O4/C) were synthesized by a simple hydrothermal reaction and applied as solid-phase extraction (SPE) sorbents to extract trace polycyclic aromatic hydrocarbons (PAHs) from environmental water samples. The Fe3O4/C sorbents possess high adsorption capacity and extraction efficiency due to strong adsorption ability of carbon materials and large surface area of nanoparticles, and only 50 mg of sorbents are required to extract PAHs from 1000 mL water samples. The adsorption attains equilibrium rapidly and analytes are eluted with acetonitrile readily. Salinity and solution pH have no obvious effect on the recoveries of PAHs, which avoids fussy adjustment to water sample before extraction. Under optimized conditions, the detection limits of PAHs are in the range of 0.2–0.6 ng L−1. The accuracy of the method was evaluated by the recoveries of spiked samples. Good recoveries (76–110%) with low relative standard deviations from 0.8% to 9.7% are achieved. This new SPE method provides several advantages, such as high extraction efficiency, high breakthrough volumes, convenient extraction procedure, and short analysis times. To our knowledge, this is the first time that Fe3O4/C nanoparticles are used for the pretreatment of environmental water samples.  相似文献   

15.
In the present work, a novel sample pre-treatment technique for the determination of trace concentrations of some insecticide compounds in aqueous samples has been developed and applied to the determination of the selected analytes in environmental water samples. The extraction procedure is based on coupling polypropylene hollow fiber liquid phase microextraction (HF-LPME) with gas chromatography by flame thermionic detection (GC-FTD). For the development of the method, seven organophosphorous insecticides (dichlorvos, mevinphos-cis, ethoprophos, chlorpyrifos methyl, phenthoate, methidathion and carbofenothion) and one carbamate (carbofuran) were considered as target analytes. Several factors that influence the efficiency of HF-LPME were investigated and optimized including agitation, organic solvent, sample volume, exposure time, salt additives and pH. The optimized methodology exhibited good linearity with correlation coefficient = 0.990. The analytical precision for the target analytes ranged from 4.3 to 11.1 for within-day variation and 4.6 to 12.0% for between-day variation. The detection limits for all analytes were found in the range from 0.001 to 0.072 microg/L, well below the limits established by the EC Drinking Water Directive (EEC 80/778). Relative recoveries obtained by the proposed method from drinking and river water samples ranged from 80 to 104% with coefficient of variations ranging from 4.5 to 10.7%. The present methodology is easy, rapid, sensitive and requires small sample volumes to screen environmental water samples for insecticide residues.  相似文献   

16.
A method suitable for the determination of unmetabolized polycyclic aromatic hydrocarbons (PAHs) excreted at trace levels (ng/L) in human urine for the monitoring of exposure of the general population to PAH contamination was developed. PAHs were determined, after enrichment by solid-phase extraction on polyurethane foam (PUF) chips, by HPLC with fluorescence detection. Different parameters affecting analyte extraction to the PUF, including urine salting-out and organic additives, and optimization of conditions for clean-up and desorption have been investigated. Optimized conditions were 40 mL acidified urine sample, added with magnesium sulfate, tetrahydrofuran and a 2 cm3 PUF chip, and extracted by shaking at 30 rpm for 1 h at ambient temperature. Desorption was performed, after a clean-up step with diluted sodium hydroxide, using a small amount of diethyl ether. The recovery of PAH congeners from spiked urines was >90% in the 2-100 ng/L range; the detection limit was 0.1-0.5 ng/L, depending on the considered PAH congener; day-to-day precision, at 50 ng/L native PAH content, was CV = 10-20%. The proposed technique provides a simple, economical and effective procedure for the determination of trace amounts of unmetabolized PAHs excreted in human urine spot samples.  相似文献   

17.
Summary A novel method for the extraction into an aqueous medium of PAHs in soil is described, where sodium dodecyl sulphate (SDS) is used as micelle former. After optimisation of this step using a multivariate approach, recoveries of the target analytes from spiked soil ranging between 98.3%–99.7% were obtained when the samples were subjected to extraction with 25 mL of an aqueous SDS solution (2.9 10−2 mol L−1) while irradiated with focused microwaves at 240 W for 40 min. The overall method involving determination of the extracted compounds consists of three steps: 1) extraction of the analytes into the aqueous micellar medium assisted by focused microwaves; 2) trapping of the analytes on a C18 cartridge for clean up and preconcentration and; 3) HPLC separation with fluorimetric detection. The method was validated using the certified reference material CRM 524 and the results found were in agreement with the certified values.  相似文献   

18.
熊珺  谢思龙  赖毅东 《色谱》2011,29(2):115-119
建立了分散液-液微萃取与气相色谱-质谱联用同时测定环境水样中痕量2,4-二硝基甲苯和磷酸三(2-氯乙基)酯的新方法。对影响萃取效率的因素进行了详细的考察和优化,确定采用的最佳萃取条件为: 将0.8 mL乙醇和60 μL氯仿的混合溶液快速注入5.0 mL的样品溶液中,振动混匀120 s后,离心分离,吸取沉积在试管底部的氯仿相直接进样分析。该方法对磷酸三(2-氯乙基)酯和2,4-二硝基甲苯的检出限(信噪比为3)分别为0.01和0.04 μg/L,富集倍数分别为96.6和127.5;两种物质的线性范围达3到4个数量级;日内和日间测定的相对标准偏差(RSDs, n=6)分别为8.6%~11.5%和8.9%~12.0%。将该方法用于环境水样中2,4-二硝基甲苯和磷酸三(2-氯乙基)酯的分析,其加标回收率为102.1%~110.9%。方法具有操作简单、方便快速、灵敏度高、无交叉污染和环境友好等优点。  相似文献   

19.
Zhou  Qingxiang  Xiao  Junping  Xie  Guohong  Wang  Weidong  Ding  Yujie  Bai  Huahua 《Mikrochimica acta》2009,164(3-4):419-424

A sensitive method was developed using new carbon nanomaterial, multiwalled carbon nanotubes, as solid phase extraction adsorbents followed by high performance liquid chromatography with UV detection for determination of six pyrethroid pesticides at trace level in environmental water samples. Parameters influencing the extraction efficiency were investigated in detail. Under the optimal conditions, detection limits of 0.7–5.0 ng L−1 were obtained for six pyrethroid pesticides, the linear ranges were between 0.1 and 40 μg L−1 and the precisions were in the range of 2.0–5.8%. The method has been applied to determine the six target compounds in tap water, well water, river water and reservoir water. Good recoveries were obtained for all target analytes and these results indicated that the method developed can be used in the determination of such compounds at trace levels in environmental water samples.

  相似文献   

20.
张建华  黄颖  陈晓秋  陈金花  李辉  陈国南 《色谱》2009,27(6):799-803
建立了简便、快速、有效的分散液-液微萃取-高效液相色谱-荧光检测(DLLME-HPLC-FLD)测定环境水样中15种多环芳烃(PAHs)的方法。重点探讨了萃取剂的种类和用量、分散剂的种类和用量以及萃取时间等对PAHs萃取效率的影响。在优化的条件下,评价了方法的可靠性。15种PAHs在0.01~10 μg/L范围内呈良好的线性关系,相关系数r均不小于0.9913,峰面积的相对标准偏差(RSD)在2.3%~4.7%之间(n=6)。在优化条件下,富集因子和萃取回收率良好,分别为674~1032和67.4%~103.2%,15种PAHs的检出限(S/N=3)在0.0003~0.002 μg/L之间。建立的方法应用于敖江水样中PAHs的检测,平均加标回收率在79.5%~92.3%之间,RSD在4.3%~6.7%范围内(n=5)。该方法适用于环境水样中痕量PAHs的分析。  相似文献   

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