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1.
Regueiro J Llompart M Garcia-Jares C Cela R 《Analytical and bioanalytical chemistry》2007,388(5-6):1095-1107
Gas chromatographic analysis of polybrominated diphenyl ethers (PBDEs) has been evaluated in an attempt to achieve better
control of the separation process, especially for highly substituted congeners. Use of a narrow-bore capillary column enabled
adequate determination of tetra, penta, hexa, hepta, octa, nona and decaBDE congeners in only one chromatographic run while
maintaining resolution power similar to that of conventional columns. A micro electron-capture detector (GC–μECD) was used.
Chromatographic conditions were optimized by multifactorial experimental design, with the objective of obtaining not only
high sensitivity but also good precision. In this way two different approaches to maximizing response and minimizing variability
were tested, and are fully discussed. These optimum chromatographic conditions were then used to determine PBDEs extracted
from domestic dust samples by microwave-assisted solvent extraction (MASE). Quantitative recovery (90–108%) was achieved for
all the PBDEs and method precision (RSD < 13%) was satisfactory. Accuracy was tested by use of the standard reference material
SRM 2585, and sub-ng g−1 limits of detection were obtained for all compounds except BDE-209 (1.44 ng g−1). Finally, several samples of house dust were analysed by use of the proposed method and all the target PBDEs were detected
in all the samples. BDE-209 was the predominant congener. Amounts varied from 58 to 1615 ng g−1 and the average contribution to the total PBDE burden of 52%. The main congeners of the octaBDE mixture (BDE-183, BDE-197,
BDE-207 and BDE-196) also made an important contribution (29%) to the total. These are the first data about the presence of
these compounds in European house-dust samples. Finally, the sum of the main congeners in the pentaBDE commercial mixture
(BDE-47, BDE-99, and BDE-100) contributed 14% to the total.
Figure Polybrominated diphenyl ethers in House Dust 相似文献
2.
Manfred P?hlein Raquel Urpi Bertran Marion Wolf Rudi van Eldik 《Analytical and bioanalytical chemistry》2009,394(2):583-595
Reference materials for the analysis of polybrominated diphenyl ethers, polybrominated biphenyls and other common brominated
flame retardants (FR) in styrenic polymers were prepared to suit the demands of actual restriction of the use of certain hazardous
substances in electrical and electronic equipment analytics. Three methods of preparation were employed, viz. pellet forming,
dissolution/vaporisation and extrusion, whereby extrusion proved to be the most suitable method. For extrusion, three procedures
of pre-mixing were investigated: the polymers were either mixed with FR powder, FR solutions or FR concentrates that were
taken from waste industrial polymers. The latter procedure proved to be most appropriate in terms of analyte concentration,
predictability and recovery. The homogeneity of the samples, as well as the chemical and thermal long-term stabilities, was
investigated. The result was an optimised method to prepare a suitable reference material for laboratory use.
Figure
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Solà Vázquez A Martín A Costa-Fernandez JM Ruiz Encinar J Bordel N Pereiro R Sanz-Medel A 《Analytical and bioanalytical chemistry》2007,389(3):683-690
There is an increasing concern regarding the toxicity and environmental distribution and impact of brominated organic compounds
employed as flame retardants. Thus, present interest in searching for new analytical techniques and methods allowing a rapid,
simple and reliable detection of those compounds in materials and wastes potentially containing such flame retardants is not
surprising. The feasibility of using radiofrequency glow discharge plasma spectrometry coupled with optical emission spectrometry
(rf-GD-OES) as a rapid and simple tool to directly analyse bromine-containing flame-retardant polymeric layers is investigated
here. Polymeric layers for calibration were made by mixing appropriate amounts of tetrabromobisphenol A, bisphenol A, phloroglucinol
and diphenylmethane-4,4′-diisocyanate in tetrahydrofuran. The corresponding blanks (polymers without tetrabromobisphenol A)
were also prepared. Detection of bromine was investigated both in the visible (at 470.48 nm) and in the near-infrared (at
827.24 nm) regions, using a charge-coupled device for detection. Discharge parameters affecting the emission intensity of
bromine were first optimized (in argon and helium as possible plasma gases) and the analytical performance characteristics
were then evaluated. The best detection limit (0.044% Br) was achieved measuring Br I 827.24 nm in a He discharge, using a
forward power of 70 W and a pressure of 45 Torr. The linearity range extended up to 27% Br. Finally, the applicability of
the rf-GD-OES method proposed to the quantitative analysis of bromine in solid materials coated with flame-retardant commercial
paints was successfully demonstrated.
Figure Flame Retardants 相似文献
4.
Pierre Labadie Khawla Tlili Fabrice Alliot Catherine Bourges Annie Desportes Marc Chevreuil 《Analytical and bioanalytical chemistry》2010,396(2):865-875
The aim of this work was to develop procedures for the simultaneous determination of selected brominated flame retardants
(BFRs) in river water and in river bed sediment. The target analytes were polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol
A (TBBPA). To determine dissolved BFRs, a novel mixed-mode solid-phase extraction procedure was developed by combining a hydrophobic
sorbent (C18) with a silica-based anion exchange sorbent, so as to overcome the negative artefact induced by dissolved organic carbon.
Extraction recoveries exceeded 73% for most analytes, except for BDE-183 and BDE-209 (57%). As regards suspended sediment
and river bed sediment, extraction was carried out by means of ultrasonication (recoveries: 73–94%). These procedures, combined
to gas chromatography coupled to negative chemical ionisation mass spectrometry (GC-NCI-MS), enabled the determination of
BFRs at trace level: 3-160 pg L−1 in river water, 5–145 pg g−1 in bed sediment. These methods were applied to the determination of PBDEs and TBBPA in a suburban river (near Paris, France).
PBDEs were systematically detected in the water column (ΣBDEs, 2,300–4,300 pg L−1); they partitioned between the dissolved and particulate phases and BDE-209 was the dominant congener, followed by BDE-99
and BDE-47. TBBPA was detected in the dissolved phase only (<35–68 pg L−1). All selected BFRs were ubiquitous in bed sediments and levels ranged from 3,100 to 15,100 pg g−1 and from 70 to 280 pg g−1 (dry weight), for ΣBDEs and TBBPA, respectively. 相似文献
5.
An intercomparison to establish the performance of routine laboratories in the determination of polybrominated flame retardants
in polymers was organised. Commercial poly(ethyleneterephthalate) was fortified with technical pentabromodiphenyl ether, octabromodiphenyl
ether and decabromodiphenyl ether mixtures and with a decabromobiphenyl technical mixture at 0.4–0.8 g/kg. Homogeneity and
stability of the total Br content in the material was confirmed. Thirty-seven laboratories from Europe, Asia and the Americas
submitted results. Relative repeatability standard deviations for individual congeners ranged from 7 to 17%. Relative between-laboratory
standard deviations ranged from 22 to 61%. No significant influence of a common standard, application of a standard method
or method parameters could be identified. The quality and uncertainty of the results of this study are significantly worse
than those reported in the environmental field and indicate a clear need for a learning process among the laboratories involved.
Figure Mandel’s h (between labs): critical level: 1.91 相似文献
6.
Aguinaga N Campillo N Viñas P Hernández-Córdoba M 《Analytical and bioanalytical chemistry》2008,391(4):1419-1424
This paper describes a headspace solid-phase microextraction (HS-SPME) procedure coupled to gas chromatography with mass spectrometric
detection (GC–MS) for the determination of eight PAHs in aquatic species. The influence of various parameters on the PAH extraction
efficiency was carefully examined. At 75 °C and for an extraction time of 60 min, a polydimethylsiloxane–divinylbenzene (PDMS/DVB)
fiber coating was found to be most suitable. Under the optimized conditions, detection limits ranged from 8 to 450 pg g−1, depending on the compound and the sample matrix. The repeatability varied between 7 and 15% (RSD). Accuracy was tested using
the NIST SRM 1974b reference material. The method was successfully applied to different samples, and the studied PAHs were
detected in several of the samples.
Figure Headspace SPME sampling followed by GC–MS facilitates routine monitoring of PAHs in aquatic species 相似文献
7.
Akifumi Eguchi Tomohiko Isobe Karri Ramu 《International journal of environmental analytical chemistry》2013,93(4):348-356
An analytical method for higher brominated congeners of polybrominated diphenyl ethers (PBDEs) was optimised using a gas chromatograph equipped with an electron impact ionisation-quadrupole mass spectrometer (GC-EI-qMS) and five native PBDEs and three 13C12-labelled congeners in biological and environmental samples (mussels, sediment, dust). In the optimised instrumental conditions, abundance and repeatability improved with increase in temperature of the ion source. The instrumental detection limits (IDLs) for BDE-196, BDE-197, BDE-206, BDE-207 and BDE-209 were 0.1, 0.1, 0.2, 0.3 and 0.6?pg, respectively. When compared to the previous reports, the IDLs were the same as for electron capture negative ionisation (ECNI) or EI-double focusing magnetic sector (EI-Sector) mass spectrometer, indicating that sensitive determination could be achieved using a conventional GC-EI-qMS. Validation of the method was carried out by the analysis of reference materials and mussel samples. We confirmed that the concentrations quantified using this method was in the range of reported values for reference materials. Similar concentrations were found in mussels, which were analysed previously by our group. Thus, we conclude that a conventional GC-EI-qMS can be applied for analysis of higher brominated PBDEs in various environmental and biota matrices. 相似文献
8.
A method is described for determination of residues of the insecticide Etofenprox in environmental samples. Anionic surfactant
micelle-mediated extraction (coacervation extraction) was evaluated for isolation of Etofenprox before HPLC. The optimum conditions
used for extraction included: 0.09 g sodium dodecanesulfonate (SDoS), 3.1 mL (3.3, for concentrations below 0.04 mg L−1) 12 mol L−1 HCl, 5 min vortex stirring, 5 min centrifugation at 4000 rpm, 2 h equilibration time. The limits of quantification (LOQ)
and detection (LOD) were 0.01 and 0.004 mg L−1, respectively, and recoveries obtained from five real samples ranged from 94.33±2.48 to 100.13±2.71%. The precision of the
method was good; relative standard deviations (RSD) were less than 7%.
相似文献
9.
Pérez Pavón JL García Pinto C Guerrero Peña A Moreno Cordero B 《Analytical and bioanalytical chemistry》2008,391(2):599-607
In the present work we report the results obtained with a methodology based on direct coupling of a headspace generator to
a mass spectrometer for the identification of different types of petroleum crudes in polluted soils. With no prior treatment,
the samples are subjected to the headspace generation process and the volatiles generated are introduced directly into the
mass spectrometer, thereby obtaining a fingerprint of volatiles in the sample analysed. The mass spectrum corresponding to
the mass/charge ratios (m/z) contains the information related to the composition of the headspace and is used as the analytical signal for the characterization
of the samples. The signals obtained for the different samples were treated by chemometric techniques to obtain the desired
information. The main advantage of the proposed methodology is that no prior chromatographic separation and no sample manipulation
are required. The method is rapid, simple and, in view of the results, highly promising for the implementation of a new approach
for oil spill identification in soils.
Figure PCA score plots illustrate clear discrimination of types of crude oil in polluted soil samples (e.g. results are shown for
vertisol) 相似文献
10.
Polo M Casas V Llompart M García-Jares C Cela R 《Journal of chromatography. A》2006,1124(1-2):121-129
A depletion solid-phase microextraction (SPME) method based on multiple SPME extraction was applied to estimate fibre coating-water distribution constants (Kfs) of brominated flame retardants. Several polybrominated diphenyl ethers (PBDEs) including compounds present in the commercial mixture "Pentamix", and two polybrominated biphenyls (PBBs) were considered as target analytes. One hundred-micrometer poly(dimethylsiloxane) (PDMS) coating fibre was selected to estimate partition coefficients. SPME kinetics studies at 25 and 100 degrees C were performed. Kfs values obtained at both temperatures for brominated flame retardants were compared with the corresponding octanol-water partition coefficients (Kow) values found in literature. A linear log-log relationship between Kow with Kfs was found. To the best of our knowledge, this is the first study where brominated flame retardants Kfs values are estimated. 相似文献
11.
Aguinaga N Campillo N Viñas P Hernández-Córdoba M 《Analytical and bioanalytical chemistry》2008,391(3):753-758
A sensitive and solvent-free method for the determination of ten polycyclic aromatic hydrocarbons, namely, naphthalene, acenaphthylene,
acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene and chrysene, with up to four aromatic rings, in milk samples using headspace solid-phase microextraction and
gas chromatography–mass spectrometry detection has been developed. A polydimethylsiloxane–divinylbenzene fiber was chosen
and used at 75°C for 60 min. Detection limits ranging from 0.2 to 5 ng L−1 were attained at a signal-to-noise ratio of 3, depending on the compound and the milk sample under analysis. The proposed
method was applied to ten different milk samples and the presence of six of the analytes studied in a skimmed milk with vegetal
fiber sample was confirmed. The reliability of the procedure was verified by analyzing two different certified reference materials
and by recovery studies.
Figure Milk is safe, healthy food 相似文献
12.
Lee KC Cheuk MW Chan W Lee AW Zhao ZZ Jiang ZH Cai Z 《Analytical and bioanalytical chemistry》2006,386(7-8):2225-2232
A reversed-phase HPLC method has been developed for determination of twelve intact glucosinolates—glucoiberin, glucocheirolin,
progoitrin, sinigrin, epiprogoitrin, glucoraphenin, sinalbin, gluconapin, glucosibarin, glucotropaeolin, glucoerucin, and
gluconasturtiin—in ten traditional Chinese plants. The samples were extracted with methanol and the extracts were cleaned
on an activated Florisil column. A mobile phase gradient prepared from methanol and 30 mmol L−1 ammonium acetate at pH 5.0 enabled baseline separation of the glucosinolates. Glucosinolate detection was confirmed by quadrupole
time-of-flight tandem mass spectrometric analysis in negative-ionization mode. Detection limits ranged from 0.06 to 0.36 μg
g−1 when 5 g of dried plant was analyzed. Recoveries of the glucosinolates were better than 85% and precision (relative standard
derivation, n = 3) ranged from 5.3 to 14.6%. Analysis of the glucosinolates provided scientific evidence enabling differentiation of three
pairs of easily confused plants.
Figure Glucosinolates Analysis for the Differentiation of Easily-Confusing Herbs 相似文献
13.
An X-ray fluorescence method (XRF) is presented that allowed low detection limits (at the 0.1–23 ng mL−1 level) to be obtained for Cr, Mn, Fe, Ni, Zn, Sr, Pb, Bi and Br in water. The samples were prepared using a thin layer method. Trace elements were determined via the calibration curve and standard addition. Absorption effects and inhomogenities in prepared samples were checked for using the emission–transmission method and internal standards, respectively. The results from the XRF method were compared with the results from the inductively coupled plasma atomic emission spectrometry method.
相似文献
14.
Solid-phase microextraction gas chromatography-mass spectrometry determination of fragrance allergens in baby bathwater 总被引:1,自引:0,他引:1
J. Pablo Lamas Lucia Sanchez-Prado Carmen Garcia-Jares Maria Llompart 《Analytical and bioanalytical chemistry》2009,394(5):1399-1411
A method based on solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) has been optimized for
the determination of fragrance allergens in water samples. This is the first study devoted to this family of cosmetic ingredients
performed by SPME. The influence of parameters such as fibre coating, extraction and desorption temperatures, salting-out
effect and sampling mode on the extraction efficiency has been studied by means of a mixed-level factorial design, which allowed
the study of the main effects as well as two-factor interactions. Excluding desorption temperature, the other parameters were,
in general, very important for the achievement of high response. The final procedure was based on headspace sampling at 100 °C,
using polydimethylsiloxane/divinylbenzene fibres. The method showed good linearity and precision for all compounds, with detection
limits ranging from 0.001 to 0.3 ng mL−1. Reliability was demonstrated through the evaluation of the recoveries in different real water samples, including baby bathwater
and swimming pool water. The absence of matrix effects allowed the use of external standard calibration to quantify the target
compounds in the samples. The proposed procedure was applied to the determination of allergens in several real samples. All
the target compounds were found in the samples, and, in some cases, at quite high concentrations. The presence and the levels
of these chemicals in baby bathwater should be a matter of concern.
Baby exposure to fragrance allergens and other cosmetic ingredients through the daily bath 相似文献
15.
A novel headspace solid-phase microextraction method for the exact determination of organochlorine pesticides in environmental soil samples 总被引:2,自引:0,他引:2
Zhao R Wang X Yuan J Jiang T Fu S Xu X 《Analytical and bioanalytical chemistry》2006,384(7-8):1584-1589
A novel method of determining organochlorine pesticides (OCPs) is described. It is based on solid-phase microextraction (SPME) and gas chromatography–electron capture detection. During the development of the method, soil samples were prepared, spiked with standard solution, and then aged for some time. Extraction conditions such as the extraction time, the NaCl content, the volume of water, the extraction temperature and the desorption time were investigated and optimized. The limits of detection obtained using the method ranged from 0.10 to 0.51 ng g−1, and relative standard deviations were lower than 10% for most organochlorine pesticides. Real soil samples were successfully analyzed using the proposed method. The results from the method developed here were in good agreement with those obtained using ultrasonic extraction. The result demonstrates that aging soils spiked with standard solution is an important method development step, because the soil samples obtained using this approach are more like real soils than those obtained when aging is not used.
相似文献
16.
Alexandra Papachlimitzou Jonathan L. Barber Sara Losada Philippe Bersuder Robin J. Law 《Journal of chromatography. A》2012
This review provides a summary of various analytical methodologies applied to the determination of “novel” brominated flame retardants (NBFRs) in various environmental compartments, as reported in peer reviewed literature, either in print or online, until the end of 2010. NBFRs are defined here as those brominated flame retardants (BFRs) which are either new to the market or newly/recently observed in the environment. The preparation and extraction of sediment, water, sewage sludge, soil, air and marine biota samples, the extract clean-up/fractionation and subsequent instrumental analysis of NBFRs are described and critically examined. Generally, while the instrumental analysis step mainly relies on mass-spectrometric detection specifically developed for NBFRs, and hyphenated to liquid or gas chromatography, preceding steps tend to replicate methodologies applied to the determination of traditional BFRs such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). Shortcomings and gaps are discussed and recommendations for future development are given. 相似文献
17.
Boron carbide is widely used as industrial material, because of its extreme hardness, and as a neutron absorber. As part of
a round-robin exercise leading to certification of a new reference material (ERM-ED102) which was demanded by the industry
we analysed nitrogen in boron carbide by inert gas fusion analysis (GFA) and instrumental photon activation analysis (IPAA)
using the 14N(γ,n)13N nuclear reaction. The latter approach is the only non-destructive method among all the methods applied. By using photons
with energy below the threshold of the 12C(γ,n)11C reaction, we hindered activation of matrix and other impurities. A recently installed beam with a very low lateral activating
flux gradient enabled us to homogeneously activate sample masses of approximately 1 g. Taking extra precautions, i.e. self-absorption
correction and deconvolution of the complex decay curves, we calculated a nitrogen concentration of 2260 ± 100 μg g−1, which is in good agreement with our GFA value of 2303 ± 64 μg g−1. The values are the second and third highest of a rather atypical (non-S-shape) distribution of data of 14 round-robin participants.
It is of utmost importance for the certification process that our IPAA value is the only one not produced by inert gas fusion
analysis and, therefore, the only one which is not affected by a possible incomplete release of nitrogen from high-melting
boron carbide.
Figure Twin-Detector system for analyzing spatially extended samples 相似文献
18.
Analytical procedure for determination of the time profile of eprinomectin excretion in sheep faeces
Kozuh Erzen N Hodoscek L Cerkvenik-Flajs V 《Analytical and bioanalytical chemistry》2007,387(4):1329-1335
An analytical procedure has been introduced to enable study of the time profile of eprinomectin excretion in sheep faeces.
Eprinomectin was extracted from sheep faeces with acetonitrile, the extract was cleaned by solid-phase extraction (SPE), and,
after derivatization by reaction with N-methylimidazole, trifluoroacetic anhydride, and acetic acid, eprinomectin was analysed by high-performance liquid chromatography
(HPLC) with fluorescence detection. The method has a low detection limit (1.0 ng g−1 of moist sheep faeces), a low quantification limit (2.5 ng g−1 of moist sheep faeces), good recovery (in the range 78.8 to 87.1%), and good reproducibility (RSD<10%). The method was used
to study the time-profile of excretion of eprinomectin in sheep faeces after a single topical administration of 0.5 mg kg−1 b.w. of the drug. Because of its good recovery, precision, and sensitivity, the method has also proved applicable to further
ecotoxicological studies of eprinomectin.
Figure Autochthonous Slovenian dairy breed sheep – Istrian Pramenka 相似文献
19.
In the present study a headspace solid-phase dynamic extraction method coupled to gas chromatography–mass spectrometry (HS-SPDE-GC/MS)
for the trace determination of volatile halogenated hydrocarbons and benzene from groundwater samples was developed and evaluated.
As target compounds, benzene as well as 11 chlorinated and brominated hydrocarbons (vinyl chloride, dichloromethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, carbon tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, bromoform) of environmental
and toxicological concern were included in this study. The analytes were extracted using a SPDE needle device, coated with
a poly(dimethylsiloxane) with 10% embedded activated carbon phase (50-μm film thickness and 56-mm film length) and were analyzed
by GC/MS in full-scan mode. Parameters that affect the extraction yield such as extraction and desorption temperature, salting-out,
extraction and desorption flow rate, extraction volume and desorption volume, the number of extraction cycles, and the pre-desorption
time have been evaluated and optimized. The linearity of the HS-SPDE-GC/MS method was established over several orders of magnitude.
Method detection limits (MDLs) for the compounds investigated ranged between 12 ng/L for cis-dichloroethylene and trans-dichloroethylene and 870 ng/L for vinyl chloride. The method was thoroughly validated, and the precision at two concentration
levels (0.1 mg/L and a concentration 5 times above the MDL) was between 3.1 and 16% for the analytes investigated. SPDE provides
high sensitivity, short sample preparation and extraction times and a high sample throughput because of full automation. Finally,
the applicability to real environmental samples is shown exemplarily for various groundwater samples from a former waste-oil
recycling facility. Groundwater from the site showed a complex contamination with chlorinated volatile organic compounds and
aromatic hydrocarbons.
Figure SPDE Principle 相似文献
20.
Determining sulfamonomethoxine and its acetyl/hydroxyl metabolites in chicken plasma under organic solvent-free conditions 总被引:1,自引:0,他引:1
Furusawa N 《Analytical and bioanalytical chemistry》2006,385(8):1570-1574
A quantitative technique is described for a sample preparation followed by high performance liquid chromatography method for
the simultaneous determination of sulfamonomethoxine and its metabolites, N
4-acetyl SMM and 2,6-dihydroxy SMM, in chicken plasma. The average recoveries, analytical total time, and limits of quantitation
were ≥80% (relative standard deviations (SD) ≤6%), <30 min sample-1 (12 samples in 2 h), and ≤0.09 μg ml−1, respectively. The procedure, performed under 100% aqueous conditions, uses no organic solvents and toxic reagents at all
and is, therefore, harmless to the environment and humans.
相似文献