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1.
Walter Vetter Bernd Luckas Frans Biermans Manfred Mohnke Harald Rotzsche 《Journal of separation science》1994,17(12):851-858
Eighty one polychlorinated biphenyls (PCBs) and nineteen chlorinated pesticide standards have been analyzed on a newly developed apolar high resolution gas chromatography (HRGC) column. Emphasis was placed on the determination of PCB indicator congeners which are part of national regulations, and of toxic coplanar PCB congeners. The new column enables almost unambiguous quantification of the PCB indicator congeners (PCB 138 can be separated from both PCB 163 and PCB 164; PCB 28 and PCB 31 were also separated and no coelution was observed for PCB 52, PCB 118, and PCB 180). The new column furnished better results than CP-Sil 8 for the analysis of PCB indicator congeners in a sample of seal blubber. 相似文献
2.
Michal Zapadlo Ján Krupčík Pavel Májek Daniel W. Armstrong Pat Sandra 《Journal of chromatography. A》2010,1217(37):5859-5867
The orthogonality of three columns coupled in two series was studied for the congener specific comprehensive two-dimensional GC separation of polychlorinated biphenyls (PCBs). A non-polar capillary column coated with poly(5%-phenyl–95%-methyl)siloxane was used as the first (1D) column in both series. A polar capillary column coated with 70% cyanopropyl-polysilphenylene-siloxane or a capillary column coated with the ionic liquid 1,12-di(tripropylphosphonium)dodecane bis(trifluoromethane-sulfonyl)imide were used as the second (2D) columns. Nine multi-congener standard PCB solutions containing subsets of all native 209 PCBs, a mixture of 209 PCBs as well as Aroclor 1242 and 1260 formulations were used to study the orthogonality of both column series. Retention times of the corresponding PCB congeners on 1D and 2D columns were used to construct retention time dependences (apex plots) for assessing orthogonality of both columns coupled in series. For a visual assessment of the peak density of PCBs congeners on a retention plane, 2D images were compared. The degree of orthogonality of both column series was, along the visual assessment of distribution of PCBs on the retention plane, evaluated also by Pearson's correlation coefficient, which was found by correlation of retention times tR,i,2D and tR,i,1D of corresponding PCB congeners on both column series. It was demonstrated that the apolar + ionic liquid column series is almost orthogonal both for the 2D separation of PCBs present in Aroclor 1242 and 1260 formulations as well as for the separation of all of 209 PCBs. All toxic, dioxin-like PCBs, with the exception of PCB 118 that overlaps with PCB 106, were resolved by the apolar/ionic liquid series while on the apolar/polar column series three toxic PCBs overlapped (105 + 127, 81 + 148 and 118 + 106). 相似文献
3.
4.
Schantz MM Keller JM Leigh S Patterson DG Sharpless KE Sjödin A Stapleton HM Swarthout R Turner WE Wise SA 《Analytical and bioanalytical chemistry》2007,389(4):1201-1208
The Certificate of Analysis for SRM 1589a PCBs, Pesticides, PBDEs, and Dioxins/Furans in Human Serum has been updated to include
certified concentration values for 27 polychlorinated biphenyl (PCB) congeners, three chlorinated pesticides, and four polybrominated
diphenyl ether (PBDE) congeners as well as reference concentration values for 27 additional PCB congeners, six additional
chlorinated pesticides, three additional PBDE congeners, and selected polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). This represents an addition of concentration values for 29 PCB
congeners and for PBDE congeners that were not quantified in the previous issue of SRM 1589a. With the increased number of
certified and reference concentration values for PCBs and the inclusion of certified and reference concentration values for
PBDEs, this serum material will be more useful as a reference material for contaminant monitoring in human tissues and fluids.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
5.
Poster DL Kucklick JR Schantz MM Porter BJ Leigh SD Wise SA 《Analytical and bioanalytical chemistry》2003,375(2):223-241
The concentrations of a wide range of polychlorinated biphenyl congeners (PCBs) and chlorinated pesticides in a fish tissue Standard Reference Material (SRM) have been determined using multiple methods of analysis. This material, SRM 1946, Lake Superior Fish Tissue, was recently issued by the National Institute of Standards and Technology (NIST) and complements a suite of marine environmental natural-matrix SRMs that are currently available from NIST for the determination of organic contaminants such as aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), PCBs, and chlorinated pesticides. SRM 1946 is a fresh tissue homogenate (frozen) prepared from filleted adult lake trout (Salvelinus namaycush namaycush) collected from the Apostle Islands region of Lake Superior. SRM 1946 has certified and reference concentrations for PCB congeners, including the three non- ortho PCB congeners, and chlorinated pesticides. Certified concentrations are available for 30 PCB congeners and 15 chlorinated pesticides. Reference concentrations are available for 12 PCB congeners and 2 chlorinated pesticides. In addition, SRM 1946 is characterized for additional chemical constituents and properties: fatty acids, extractable fat, methylmercury, total mercury, selected trace elements, proximates, and caloric content. The characterization of chlorinated compounds is described in this paper with an emphasis on the approach used for the certification of the concentrations of PCB congeners and chlorinated pesticides. The PCB congener and chlorinated pesticide data are also compared to concentrations in other marine natural-matrix reference materials available from NIST (fish oil, mussel tissue, whale blubber, and a second fresh frozen fish tissue homogenate prepared from filleted adult lake trout collected from Lake Michigan) and from other organizations such as the National Research Council Canada (ground whole carp), the International Atomic Energy Agency (fish homogenate), and the European Commission Joint Research Centre [fish oils (cod and mackerel) and mussel tissue]. 相似文献
6.
Bo Richter Larsen 《Journal of separation science》1995,18(3):141-151
High resolution gas chromatography has greatly changed the field of polychlorinated biphenyl (PCB) analysis. From a rough estimation of the total PCB concentration on packed column GC, the development of commercially available fused silica capillary columns in the late 1970s and early 1980s has advanced the analysis of PCBs to a point where they can be accurately measured as separated congeners. The state-of-the-art of PCB analysis in the 1990s is routine isomer-specific analysis with multi-column techniques using long (<50 m) narrow (> 0.25 mm) columns. A broad spectrum of commercially available stationary phases have been completely characterized with regard to their PCB elution profiles. 相似文献
7.
Russell M. Kinghorn Philip J. Marriott Mark Cumbers 《Journal of separation science》1996,19(11):622-626
Multidimensional chromatography was used to resolve the specific chlorobiphenyl (CB) congeners 28, 52, 101, 118, 138, 153, and 180 in technical aroclor standards. Single column analysis of polychlorinated biphenyls (PCBs) results in co-elution of key congeners with other components in the mixture; therefore using two columns of different selectivity was necessary to enhance the resolution achievable on just one column. The HT8 column (8% phenylpolycarborane-siloxane phase) has been reported to have specific selectivity characteristics for improved PCB separation. When coupled with a BPX5 column (5% phenylpolysiloxane-silphenylene phase), it has been shown here to provide unambiguous identification of 7 marker compounds which are used to monitor PCB occurrence and distribution. All seven marker CBs are present in aroclor 1254, and by adjusting the size of the heartcut window, it was possible to obtain resolution of the marker congeners from other congeners. Single column analysis is unable to achieve this result. This offers an alternative to GC-MS analysis. 相似文献
8.
M. V. Russo 《Chromatographia》2000,52(1-2):93-98
Summary Gas chromatography of polychlorinated biphenyls and chlorinated pesticides in water samples has been performed after adsorption
from a 20–200-mL sample on to a cartridge containing 100 mg diol-bonded porous silica. The PCBs are desorbed with 500 μL ethyl
acetate, which is concentrated and analysed by gas chromatography with electron-capture detection (GC-ECD).
The average recovery of 0.1 ng mL−1 PCB congeners from distilled water and from Aniene river water is≥95% (standard deviation≤2.8). Average recoveries of 25
ng mL−1 Aroclor 1254 from distilled water and from Aniene river water were, respectively, 94.4% and 92.5% (standard deviation 5.8).
In the separation of PCB congeners from the chlorinated pesticides only the aldrin (40%) was eluted with the PCBs from the
diol Sep-Pak cartridge by aqueous methanol. The method described is simple and reproducible. 相似文献
9.
Pure enantiomers of chiral (atropisomeric) polychlorinated biphenyls (PCBs) obtained by high-performance liquid chromatography were used to establish the gas chromatographic elution sequences of the (+)- and (−)-enantiomers of six PCB atropisomers on Chirasil-Dex. The elution order was found to be (−/+) for PCBs 84, 132, 136, and 176 and (+/−) for PCBs 135 and 174. The retention characteristics of all 19 tri- and tetra-ortho atropisomeric PCBs were also investigated. Nine of the atropisomers could be separated using this chiral selector. PCBs 95, 132, and 149 were completely resovled and PCBs 84, 91, 135, 136, 174, and 176 were partially separated (R = 0.7–0.9). All of the separated congeners are 2,3,6-substituted in at least one ring, and conversely – none of the congeners that lacks 2,3,6-substitution could be separated. Thus, chiral recognition and enantiomer separation seems to be strongly governed by 2,3,6-substitution. 相似文献
10.
Chlorobiphenyl (PCB) composition of extracts of subsurface soil, superficial dust and air from a contaminated landfill 总被引:1,自引:0,他引:1
L. G. Hansen D. Green J. Cochran S. Vermette B. Bush 《Analytical and bioanalytical chemistry》1997,357(4):442-448
Samples of 3 matrices (air, superficial dust and subsurface soil) from an aged PCB-containing landfill were extracted and
the extracts refined for bioassay. Acetone:hexane extraction was modestly selected for non-planar compounds. Coplanar PCBs
and PCDFs were enriched about 2-fold in the subsequent benzene:methylene chloride extracts of the soil. Extract refinement
with Florisil slurry and alumina column chromatography did not appreciably change the composition of the extracts. CB 28 (2,4,4′-triCB)
dominated in all extracts. The congener composition of soil and air were surprisingly similar, being enriched in tri- and
tetraCBs while dust retained higher proportions of congeners with 4 and 5 chlorines. It is postulated that anaerobic dechlorination
in the moist subsurface soil depleted the higher chlorinated congeners; more volatile congeners escaped into the atmosphere
while moderately chlorinated congeners were trapped in the superficial dust and debris. The refined extracts represent distinct
compositions of environmental PCB mixtures suitable for bioassay.
Received: 21 November 1995 / Revised: 9 April 1996 / Accepted: 14 April 1996 相似文献
11.
Determination of polychlorinated biphenyls by liquid chromatography–atmospheric pressure photoionization–mass spectrometry 下载免费PDF全文
Athanasios I. Moukas Nikolaos S. Thomaidis Antonios C. Calokerinos 《Journal of mass spectrometry : JMS》2014,49(11):1096-1107
This study presents the atmospheric pressure photoionization (APPI) of high‐chlorinated (five or more chlorine atoms) polychlorinated biphenyls (PCBs) using toluene as dopant, after liquid chromatographic separation. Mass spectra of PCB 101, 118, 138, 153, 180, 199, 206 and 209 were recorded by using liquid chromatography‐APPI‐tandem mass spectrometry (LC‐APPI‐MS/MS) in negative ion full scan mode. Intense peaks appeared at m/z that correspond to [M ? Cl + O]? ions, where M is the analyte molecule. Furthermore, a detailed strategy, which includes designs of experiments, for the development and optimization of LC‐APPI‐MS/MS methods is described. Following this strategy, a sensitive and accurate method with low instrumental limits of detection, ranging from 0.29 pg for PCB 209 to 8.3 pg for PCB 101 on column, was developed. For the separation of the analytes, a Waters XSELECT HSS T3 (100 mm × 2.1 mm, 2.5 µm) column was used with methanol/water as elution system. This method was applied for the determination of the above PCBs in water samples (surface water, tap water and treated wastewater). For the extraction of PCBs from water samples, a simple liquid–liquid extraction with dichloromethane was used. Method limits of quantification, ranged from 4.8 ng l?1, for PCB 199, to 9.4 ng l?1, for PCB 180, and the recoveries ranged from 73%, for PCB 101, to 96%, for PCB 199. The estimated analytical figures were appropriate for trace analysis of high‐chlorinated PCBs in real samples. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
12.
F. Krokos C. S. Creaser C. Wright J. R. Startin 《Analytical and bioanalytical chemistry》1997,357(6):732-742
The chromatographic behavior of ortho and non-ortho polychlorinated biphenyls (PCBs) on supported carbon columns has been investigated and the structure-affinity relationship
of activated carbon towards PCB molecules established. Optimisation of the parameters controlling the elution of PCB congeners
through the carbon column led to the development of a solvent scheme for the efficient separation of (i) ortho substituted PCBs, (ii) non-ortho substituted PCBs and (iii) polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in three separate fractions. A method for the extraction, clean-up,
fractionation and determination of ortho and non-ortho substituted PCBs by GC-isotope dilution MS was developed and validated by analysis of a certified reference material. Possible
losses of PCBs during freeze-drying and interferences of aliphatic hydrocarbons during mass spectrometric determination of
ortho substituted PCBs are also discussed.
Received: 23 June 1995/Revised: 9 May 1996/Accepted: 25 May 1996 相似文献
13.
A rapid and uncomplicated method for the fractionation of PCBs leading to an isolation of the highly toxic non-ortho substituted PCBs is described. The liquid chromatographic separation was achieved on a stationary phase consisting of activated carbon and Celite 545. Using eluents with different polarity, isolation of the non-ortho substituted PCBs in a single fraction was achieved. The fractions were analysed by GC/MS. The method was tested by the determination of non-ortho substituted PCBs in technical mixtures (Aroclor 1254 and Aroclor 1242). The results were compared with those obtained by using an HPLC fractionation on a porous graphitic carbon column. Finally, the micro-column fractionation was used for the determination of non-ortho substituted PCBs in native soil samples. 相似文献
14.
A time- and cost-saving method for the congener-specific analysis of polychlorinated biphenyls (PCBs) in human serum has been developed and validated. After two fast extraction and clean-up steps, analyses were performed using gas chromatography coupled with mass spectrometry with single ion monitoring (GC/SIM-MS), either in electron impact (EI) or electron-capture negative ionization (ECNI) mode. For the determination of dioxin-like congeners, an improvement in EI-MS sensitivity is desirable and use of NI is thus preferred. The procedure was validated for 12 dioxin-like congeners by analyzing spiked samples on three different days and using (13)C(12)-labelled analogues as internal standards. When using an NCI source, the limit of quantification was assessed at 0.01 microg/L, except for PCBs #77 and #81, which cannot be reliably detected below 0.05 microg/L. For the lower chlorinated non-dioxin-like congeners, NI offers less selectivity because of limited fragmentation. Electron impact ionization and electron-capture negative ionization mode can therefore be considered to be complementary for the determination of PCB congeners in the general population. 相似文献
15.
Summary Gas chromatography of polychlorinated biphenyls and chlorinated pesticides in water samples has been performed after adsorption
from a 50–250 mL sample on to a cartridge containing 100 mg cyanopropyl-bonded porous silica. The PCBs are desorbed with 500
μL ethyl acetate, which is concentrated and analysed by gas chromatography with electron-capture detection (GC-ECD).
The average recovery of 1 ppb PCB congeners at from distilled water and from Marta river water is ≥95% (standard deviation
≤2.5). The average recovery of 20 ppb Aroclor 1260 from Marta river water was ≥91% (standard deviation ≤3.5).
In the separation of the PCBs from the chlorinated pesticides only aldrin, heptachlor and 4,4′-DDD are adsorbed with the PCBs
by the CN Sep-Pak cartridge. The method proposed is rapid, simple and reproducible. 相似文献
16.
L. G. Hansen D. Green J. Cochran S. Vermette B. Bush 《Fresenius' Journal of Analytical Chemistry》1997,357(4):442-448
Samples of 3 matrices (air, superficial dust and subsurface soil) from an aged PCB-containing landfill were extracted and
the extracts refined for bioassay. Acetone: hexane extraction was modestly selected for non-planar compounds. Coplanar PCBs
and PCDFs were enriched about 2-fold in the subsequent benzene:methylene chloride extracts of the soil. Extract refinement
with Florisil slurry and alumina column chromatography did not appreciably change the composition of the extracts. CB 28 (2,4,4′-triCB)
dominated in all extracts. The congener composition of soil and air were surprisingly similar, being enriched in tri- and
tetraCBs while dust retained higher proportions of congeners with 4 and 5 chlorines. It is postulated that anaerobic dechlorination
in the moist subsurface soil depleted the higher chlorinated congeners; more volatile congeners escaped into the atmosphere
while moderately chlorinated congeners were trapped in the superficial dust and debris. The refined extracts represent distinct
compositions of environmental PCB mixtures suitable for bioassay. 相似文献
17.
Astrid Trost W. Kleib?hmer Karl Cammann 《Fresenius' Journal of Analytical Chemistry》1997,359(3):249-253
A rapid and uncomplicated method for the fractionation of PCBs leading to an isolation of the highly toxic non-ortho substituted
PCBs is described. The liquid chromatographic separation was achieved on a stationary phase consisting of activated carbon
and Celite 545. Using eluents with different polarity, isolation of the non-ortho substituted PCBs in a single fraction was
achieved. The fractions were analysed by GC/MS. The method was tested by the determination of non-ortho substituted PCBs in
technical mixtures (Aroclor 1254 and Aroclor 1242). The results were compared with those obtained by using an HPLC fractionation
on a porous graphitic carbon column. Finally, the micro-column fractionation was used for the determination of non-ortho substituted
PCBs in native soil samples.
Received: 5 March 1997 / Revised: 4 June 1997 / Accepted: 6 June 1997 相似文献
18.
《应用有机金属化学》2017,31(2)
This study focuses on the hydrodechlorination of chlorinated arenes as well as polychlorinated biphenyls (PCBs) utilizing a resin‐supported Pd(0) catalyst. Bearing in mind the dangers associated with toxic PCBs, treatment of the remnants of industrial wastes containing PCB congeners is indispensable. One such method is reductive hydrodechlorination. Instead of utilizing traditional sources of hydrogen, ammonium formate is used for in situ hydrogen generation. Moreover, palladium nanoparticles are supported on an anionic exchange resin which makes the process recyclable with a negligible change of yield after recycling experiments. The catalyst is demonstrated in the hydrodechlorination of a wide range of chlorinated compounds and PCB congeners including aroclors 1242, 1248 and 1254. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
19.
The feasibility of comprehensive two-dimensional gas chromatography with electron-capture detection (GC x GC-ECD) for the enantioseparation of chiral PCBs from other possible interfering compounds has been evaluated. Three commercially available enantioselective beta-cyclodextrin-based capillary columns (Chirasil-Dex, BGB-172 and BGB-176SE) have been tested as first-dimension columns. Three non-enantioselective stationary phases (HT-8, BPX-50 and Supelcowax-10) were combined with the enantioselective columns to allow the unambiguous determination of the enantiomers of the target chiral PCBs. Each enantioselective first-dimension column tested was able to separate into enantiomers different PCB congeners, but in all cases, the use of Supelcowax-10 as second-dimension column provided the most satisfactory results. The Chirasil-Dex x Supelcowax-10 column combination allowed the determination of the enantiomeric fraction (EF) of PCBs 84, 91, 95, 132, 136, 149, 174 and 176 in the working standard solution, while that of congener 135 was hindered. The BGB-172 x Supelcowax-10 column set allowed a proper EF determination of congeners 45, 84, 131, 132, 135, 171, 174 and 183, while that of PCB 91 was interfered with co-elutants. The column combination BGB-176SE x Supelcowax-10 allowed the determination of all congeners that this enantioselective stationary phase was able to separate into enantiomers, i.e. PCBs 45, 91, 95, 136, 149 and 176. These column combinations have also been evaluated for the simultaneous determination of the 12 congeners with a toxic equivalency factor assigned by the WHO (PCBs 77, 81, 105, 114, 118, 123, 126, 156, 157, 167, 169, 189) and the seven indicator congeners (PCBs 28, 52, 101, 118, 138, 153 and 180), and evaluated for the analysis of food samples. 相似文献
20.
Y. Y. Shu J. E. Dowdall C. Chiu R. C. Lao 《International journal of environmental analytical chemistry》2013,93(2-4):185-194
Abstract Polychlorinated biphenyls (PCBs) are toxic, perssstent, global environmental contaminants which were formulated as complex mixtures of congeners. Many methods have been developed in the past to analyze PCB in transformer oil samples for regulatory purposes. The most important consideration in the cleanup procedure is the ability to remove the oil from the sample matrix, since trace amount of oil will interfere with the subsequent GC-MS analysis. Electron capture detection (ECD) has been the most common method for gas chromatographic analysis of PCBs because of its high sensitivity toward halogenated compounds. ECD can also respond to some non-PCB compound resulting in biased concentrations of PCB. In this work, a two-stage cleanup method, using DMSO liquid/liquid extraction and HPLC column chromatography. has been applied to two types of transformer oil. Five internal standards have been selected to show their performance in the presence of different oil matrices. The comparison of the PCB quantification at different conditions for GC-MS and GC-ECD will be demonstrated. 相似文献