High-performance liquid chromatography determination of nitrated polycyclic aromatic hydrocarbons by indirect fluorescence detection

A high-performance liquid chromatography (HPLC) method for the analysis of nitrated polcyclic aromatic hydrocarbons (NPAHs) is reported. NPAH mixtures were pre-concentrated using solid-phase extraction and well resolved on a C(18) column. They were detected using an indirect method involving the quenching of the emission from the fluorophores 5,6,7,8-tetrahydronaphthol (5,6,7,8-THN-1-OH), 7-amino-4-methyl coumarin (Coumarin 120, COU-120) and 3-hydroxy-4-(2-hydroxy-4-sulfo-1-naphthylazo)2-naphthalene carboxylic acid (Calcon carboxylic acid, CCA). Linear calibration curves were obtained in the range 1.1 x 10(-9) to 1.1 x 10(-8) mol/L. Using COU 120 as the fluorophore, the detection limit was 2.9 x 10(-10) mol/L for 1-nitronaphthalene and 2.1 x 10(-11) mol/L for 2-nitrofluorene. Recoveries of NPAHs from spiked tap water samples were between 88 and 100%.     

Determination of polycyclic aromatic hydrocarbons in edible oils and fats by on-line donor-acceptor complex chromatography and high-performance liquid chromatography with fluorescence detection

Various off-line methods for clean-up and sample enrichment are available for the analysis of polycyclic aromatic hydrocarbons (PAHs) in edible oils and fats. These methods consist of laborious and time consuming procedures. This study reports an on-line method using LC-LC coupling. After clean-up of the sample on a donor-acceptor complex chromatography (DACC) column the PAHs are transferred to and separated on an analytical HPLC column. Quantification is carried out with fluorescence detection. The DACC column clean-up is fast and is carried out during the HPLC run of the previous sample. Compared to the traditional methods this automated on-line method saves considerable time and significantly reduces the amount of solvent waste. The method uses common HPLC equipment and its performance has been evaluated.     

Trace determination of nitrated polycyclic aromatic hydrocarbons using liquid chromatography with on-line electrochemical reduction and fluorescence detection

An efficient clean-up procedure coupled with a high performance liquid chromatography (HPLC) with on-line electrochemical (EC) reduction and fluorescence detection (FLD) was developed to quantify nitrated polycyclic aromatic hydrocarbons (NPAHs) in the airborne particulate. In this process, NPAHs were extracted ultrasonically followed by analysis by using a reversed phase column with an aqueous eluent containing 70% aqueous acetonitrile and sodium monocholoroacetate as a buffer solution. The extraction efficiencies were above 83% for 1-nitropyrene and 1,3-dinitropyrene (1,3-DNP) 1,6-DNP, and 1,8-DNP, and calibration graphs were linear with very good correlation coefficients (r>0.999) and the detection limits were in the range of 1.0-2.2 pg for dinitropyrenes and nitropyrene. The proposed method provides a relatively simple and convenient procedure for determining the NPAHs samples in airborne particulate.     

Screening and determination of polycyclic aromatic hydrocarbons in seafoods using QuEChERS-based extraction and high-performance liquid chromatography with fluorescence detection

A rapid, sensitive, and accurate method for the screening and determination of polycyclic aromatic hydrocarbons (PAHs) in edible seafood is described. The method uses quick, easy, cheap, effective, rugged, and safe (QuEChERS)-based extraction and HPLC with fluorescence detection (FLD). The method was developed and validated in response to the massive Deepwater Horizon oil spill in the Gulf of Mexico. Rapid and highly sensitive PAH screening methods are critical tools needed for oil spill response; they help to assess when seafood is safe for harvesting and consumption. Sample preparation involves SPE of edible seafood portions with acetonitrile, followed by the addition of salts to induce water partitioning. After centrifugation, a portion of the acetonitrile layer is filtered prior to analysis via HPLC-FLD. The chromatographic method uses a polymeric C18 stationary phase designed for PAH analysis with gradient elution, and it resolves 15 U.S. Environmental Protection Agency priority parent PAHs in fewer than 20 min. The procedure was validated in three laboratories for the parent PAHs using spike recovery experiments at PAH fortification levels ranging from 25 to 10 000 microg/kg in oysters, shrimp, crab, and finfish, with recoveries ranging from 78 to 99%. Additional validation was conducted for a series of alkylated homologs of naphthalene, dibenzothiophene, and phenanthrene, with recoveries ranging from 87 to 128%. Method accuracy was further assessed based on analysis of National Institute of Standards and Technology Standard Reference Material 1974b. The method provides method detection limits in the sub to low ppb (microg/kg) range, and practical LOQs in the low ppb (microg/kg) range for most of the PAH compounds studied.     

Determination of some selected polycyclic aromatic hydrocarbons in environmental samples by high-performance liquid chromatography with fluorescence detection

Summary Analytical methods for the determination in environmental samples, of some selected Polycyclic Aromatic Hydrocarbons (PAH's), which are included on the EPA Priority Pollutant list, have been developed and evaluated. The methodology involves the extraction of PAH's from water samples by solvent extraction with dichloromethane. Solid samples were ultrasonically extracted with acetone/hexane and the extract was cleaned up on a silica gel/alumina column. The concentrated and cleaned up extracts were analysed by HPLC on a polymeric C₁₈ column using a gradient of acetonitrile/water as the mobile phase and fluorescence detection. Typical detection limits lie in the range of 1–30 ng ml^–1 of the analytes, but after sample pretreatment detection limits of 10–300 ng l^–1 were obtained. The extraction, clean-up and HPLC methodology was applied to the determination of selected PAH's in coal washings samples and the method was validated by the quantification of PAH's in a natural contaminated and a spiked sediment.     

Determination of polycyclic aromatic hydrocarbons in seawater by high-performance liquid chromatography with fluorescence detection following micelle-mediated preconcentration

In this work, the nonionic surfactant polyoxyethylene-10-lauryl ether has been used for the extraction and preconcentration of 14 polycyclic aromatic hydrocarbons, classified as priority pollutants by the US Environmental Protection Agency, from seawater samples. The cloud-point preconcentration previous separation by HPLC and quantification using fluorimetric detection and wavelength programming allow to determine these pollutants with detection limits ranging from 1.0 to 1.5 x 10(2) ng/l with RSDs better than 10.4%. The methodology is evaluated using well-established extraction and preconcentration methods and GC-MS.     

Determination of hydroxylated polycyclic aromatic hydrocarbons in airborne particulates by high-performance liquid chromatography with fluorescence detection.

This paper describes a highly sensitive and selective method for the determination of hydroxylated polycyclic aromatic hydrocarbons (PAHs-OH) in airborne particulates. PAHs-OH were extracted from airborne particulates with ethanol by ultrasonication. The extractant was further cleaned up by solid phase extraction (SPE) with an aminopropylsilica cartridge, and subsequently analyzed by reversed-phase high-performance liquid chromatography with fluorescence detection. 2-Hydroxy-1-acetonaphthone was used as an internal standard. By the proposed method, 2-hydroxyfluorene and 1-hydroxypyrene were identified in airborne particulates and their concentrations were determined for the first time.     

Homogeneous liquid–liquid extraction combined with high performance liquid chromatography–fluorescence detection for determination of polycyclic aromatic hydrocarbons in vegetables

In this article, homogeneous liquid–liquid extraction (HOLLE), combined with HPLC-fluorescence detector (HPLC-FLD), has been developed for the extraction and determination of polycyclic aromatic hydrocarbons (PAHs) in vegetables. ACN was used as extraction solvent for the extraction of target analytes from vegetables. When the previous extraction process was over, the ACN extract was transferred to the water-immiscible organic phase, tetrachloroethane, used as extraction solvent in HOLLE procedures. Under the optimum conditions, repeatability was carried out by spiking PAHs at concentration level of 12.5 μg/kg, the RSDs varied between 1.1 and 8.5% (n = 3). The LODs, based on S/N of 3, ranged from 0.025 to 0.25 μg/kg. Relative recoveries of PAHs from cucumber and long crooked squash samples were in the range of 72.4–104.9% and 65.5–119.3%, respectively. Compared with the conventional extraction method, the proposed method has the advantage of being quick, easy to operate, and having low consumption of organic solvent.     

Quantification of several monohydroxylated metabolites of polycyclic aromatic hydrocarbons in urine by high-performance liquid chromatography with fluorescence detection

A high-performance liquid chromatographic method with fluorescence detection has been developed to determine the urinary polycyclic aromatic hydrocarbon metabolites 2-hydroxynaphthalene, 2-hydroxyfluorene, 9-hydroxyphenanthrene, 1-hydroxypyrene and 3-hydroxybenz[a]pyrene. Solid phase extraction (SPE) was used to clean up the samples, and washing with 30% methanol was found to be the best way to remove interferences in the matrix. The method detection limits ranged from 0.044 μg/L for 1-hydroxypyrene to 1.615 μg/L for 3-hydroxybenz[a]pyrene, and the recoveries ranged between 40% for 3-hydroxybenz[a]pyrene and 99% for 2-hydroxynaphthalene. The within-day relative standard deviation was lowest for 2-hydroxynaphthalene at 0.67% and went up to 2.42% for 3-hydroxybenz[a]pyrene, and the between-day relative standard deviation ranged from 3.84% for 9-hydroxyphenanthrene to 10.42% for 2-hydroxyfluorene. The correlation coefficients were between 0.9962 and 0.9998. The developed method was successfully used to analyze samples from student volunteers in a high school.     

Selective enrichment procedures for the determination of polychlorinated biphenyls and polycyclic aromatic hydrocarbons in environmental samples by gel permeation chromatography

An improved two-step clean up procedure involving alumina-silica column chromatography and gel permeation chromatography (GPC) of air particulate matter (NBS SRM 1648) and river sediment extracts and a GPC clean up procedure for marine biota samples are described for the determination of polycyclic aromatic hydrocarbons with two to five rings and selected polychlorinated biphenyl congeners, respectively. Bio-Beads SX-12 and SX-3 were used as packing materials. The recoveries obtained varied from 52 to 78% depending on the compound. Quantitative data for NBS SRM 1648 were comparable with those described previously for this sample.     

Rapid SPE-HPLC determination of the 16 European priority polycyclic aromatic hydrocarbons in olive oils

Polycyclic aromatic hydrocarbons (PAHs) are a large class of organic compounds. It has been established that the main source of exposure to these compounds for human beings is through food, particularly fats and oils, due to the lipophilic nature of these polycyclic compounds. The aim of this work was to optimise and validate a method involving SPE and HPLC for rapid determination of the 16 European Union (EU) priority PAHs (required by the Recommendation 2005/108/EC) in vegetable oils. Two spectrofluorometric detectors and a UV-Visible detector in series were used to identify and quantify the target compounds. Linearity, recoveries, LOD, and LOQ were found to be in agreement with the performance criteria for benzo[a]pyrene (BaP) analysis as required by the Commission Directive 2005/10/EC, and satisfactory for all the compounds of interest, except for cyclopenta[c,d]pyrene, which presented a very low signal in the UV. Optimised chromatographic conditions for the separation of 25 PAHs, comprising both EPA and EU priority PAHs plus benzo[e]pyrene and benzo[b]chrysene, have been also proposed.     

超高效液相色谱荧光检测器测定土壤中多环芳烃

建立了超高效液相色谱系统(UPLC)荧光检测土壤中15种美国环境保护署(USEPA)优控的多环芳烃(PAHs),简化了土壤样品中PAHs的前处理过程。UPLC对15种PAHs分离时间为17 min,流速为0.4 mL/min。荧光检测器对15种PAHs的检出限为0.03~1.53μg/L,6次重复测定的峰面积相对标准偏差为0.12%~0.99%。除了萘和苊外,土样加标的平均回收率为82.9%~103.4%。由于色谱柱的较高分辨率以及荧光检测器的较高选择性,在定性和定量研究土壤样品中的PAHs时,提取物的硅胶柱净化步骤可以省略。     

高效液相色谱-荧光检测法测定橄榄油中4种多环芳烃

建立了高效液相色谱-荧光检测(HPLC-FLD)测定橄榄油中苯并[a]蒽、屈艹、苯并[b]荧蒽、苯并[a]芘4种多环芳烃(PAHs)的分析方法。橄榄油样品经异丙醇稀释,采用具有π-π特异性作用的固相萃取柱净化,Agilent ZORBAX Eclipse PAH色谱柱(100 m m×2.1 m m,1.8μm)分离,以水-乙腈为流动相,梯度洗脱,实现了4种化合物的基线分离,并用基质匹配校准溶液进行外标法定量。4种多环芳烃的线性范围为2.4~40μg/L,相关系数(r)为0.999 0~0.999 9,方法的定量限为0.147~0.413μg/L,加标回收率为95.5%~103.2%,日内和日间精密度(RSD)分别为0.10%~1.69%和2.48%~2.93%(n=5)。该法具有灵敏度高、检出限低、重复性好等特点,适用于橄榄油中4种PAHs快速、准确的定量检测。     

Rapid determination of trace polycyclic aromatic hydrocarbons in particulate matter using accelerated solvent extraction followed by ultra high performance liquid chromatography with fluorescence detection

A method has been developed for the trace analysis of polycyclic aromatic hydrocarbons, which are known as persistent organic pollutants and ubiquitous constituents of fine particulate matter that causes growing airborne pollution. The method, which was especially for samples of airborne particulate matter less than 2.5 μm in diameter, utilized accelerated solvent extraction and ultra high performance liquid chromatography with fluorescence detector. Four principal parameters of accelerated solvent extraction were optimized to obtain maximum extraction efficiency. Using the established synergetic programs of gradient elution and fluorescence wavelength switching, a rapid separation was achieved in 6.56 min with good linearity for 15 polycyclic aromatic hydrocarbons (coefficient of determination above 0.999). The limits of detection ranged from 0.833 to 10.0 pg/m³. The precision of the method expressed as inter‐day relative standard deviation ranged from 0.2 to 1%, which was calculated from nine repetitive measurements of 8.00 μg/L analytes. Average spiked recoveries ranged from 71.6 to 97.7%, with the exception of naphthalene. The rapid, sensitive, and accurate method can meet the pressing needs of health risk assessment and increasingly heavy daily tasks of air quality monitoring.     

应用二极管阵列串联荧光检测-高效液相色谱技术快速测定玩具材料中蒽油的4种成分

采用二极管阵列串联荧光检测-高效液相色谱法对玩具材料中蒽油的4种主要成分蒽、菲、芘、荧蒽进行了检测。样品用正己烷-丙酮溶液超声提取,硅胶小柱净化。方法的荧光检测线性范围为0.5～1000 μg/L,二极管阵列检测线性范围为0.5～1000 mg/L。加标回收、精密度试验表明4种成分的回收率为70.0%～120%,精密度为0.7%～8.8%。蒽、菲、芘、荧蒽的检出限分别为0.1、0.1、0.2、0.3 μg/L,定量限分别为0.4、0.2、0.5、0.8 μg/L。方法具有灵敏度高、检出限低的特点,适用于玩具材料中蒽油4种成分的快速定性、定量检测。     

Solid-phase clean-up in the liquid chromatographic determination of polycyclic aromatic hydrocarbons in edible oils

A solid-phase extraction (SPE) method for sample clean-up, followed by reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection is reported for the determination of polycyclic aromatic hydrocarbons (PAHs) in edible oils. The effects of experimental variables, such as washing and elution solvents, sample solvent and drying time have been studied using C18 cartridges. Recoveries and selectivity using other sorbent materials (C8, C2, CH, PH and NH2) were also examined, with C18 being the best one. The recoveries ranged between 50 and 103% depending on the molecular mass of the PAH. The limits of quantitation were lower than 1 ng/g for most PAHs and good precision was achieved. The method was validated using certified reference materials.     

Sample preparation and analytical methods for polycyclic aromatic hydrocarbons in sediment

Polycyclic aromatic hydrocarbons (PAHs) are a large category of ubiquitous persistent environmental pollutants, some of them have strong carcinogenicity to human and animals. These pollutants can easily enter the river through multiple ways including rainfall, dry deposition and water washout, and deposit in the sediment. However, it is easy for them to re-enter the river water and pollute water sources, as well as aquatic animals and plants, bringing potential harm to human health. Therefore, it is requisite to accurately analyze the PAHs in sediment. In this review, the analytical methods of PAHs in sediment, focused on the methods of sample extraction, purification, concentration and determination, are summarized.     

Analysis of phenols in pyrolysis oils by gel permeation chromatography and multidimensional liquid chromatography

A simple method with minimal manual sample preparation was developed for the analysis of phenols in pyrolysis oils. Sample pre-treatment was done by gel permeation chromatography (GPC), where the high-molecular-mass lignins were separated from the phenols. Multidimensional liquid chromatography (LC-LC) was used in the analysis of the phenolic fraction. The pre-column was used for sample clean-up and pre-fractionation before introduction of the phenolic fraction to the analytical column. The repeatability and linearity of the total GPC and LC-LC methods were excellent. The results were in accordance with the reference method in which the sample pre-treatment was done by precipitating the lignins with water, and the phenols were extracted with toluene and analysed by GC-MS.     

Determination of polycyclic aromatic hydrocarbons in water samples using high-performance liquid chromatography with amperometric detection

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).     

Characterization of polycyclic aromatic hydrocarbons in shale oil by chromatography and fluorescence densitometry

Polycyclic aromatic hydrocarbons (6-, 5-, 4- and 3-ring) were characterized in several shale oil samples. Open-column, dry-column and thin-layer chromatography were used in the separation steps. Visible fluorescence from the separated components on chromatoplates was measured directly to obtain fluorescence profiles of the distribution on the chromatoplates. The methods developed are inexpensive, reproducible, and allow rapid characterization of polycyclic aromatic hydrocarbons in shale oil samples.