共查询到20条相似文献,搜索用时 31 毫秒
1.
Analysis of trace levels of pesticides in rainwater by SPME and GC-tandem mass spectrometry after derivatisation with PFFBr 总被引:2,自引:0,他引:2
Scheyer A Briand O Morville S Mirabel P Millet M 《Analytical and bioanalytical chemistry》2007,387(1):359-368
Solid-phase microextraction (SPME) was used for the analysis of some pesticides (bromoxynil, chlorotoluron, diuron, isoproturon,
2,4-MCPA, MCPP and 2,4-D) in rainwater after derivatisation with PFBBr and gas chromatography-ion trap mass spectrometry.
The derivatisation procedure was optimized by testing different methods: direct derivatisation in the aqueous phase followed
by SPME extraction, on-fibre derivatisation and derivatisation in the injector. The best result was obtained by headspace
coating the PDMS/DVB fibre with PFBBr for 10 min followed by direct SPME extraction for 60 min at 68 °C (pH 2 and 75% NaCl).
Good detection limits were obtained for all the compounds: these ranged between 10 and 1,000 ng L−1 with a relatively high uncertainty due to the combination of derivatisation and SPME extraction steps. The optimized procedure
was applied to the analysis of pesticides in rainwater and results obtained shows that this method is a fast and simple technique
to assess the spatial and temporal variations of concentrations of pesticides in rainwater. 相似文献
2.
A new cloud vapor zone (CVZ)-based headspace solid-phase microextraction (HS-SPME) technique has been demonstrated with the
capability of heating the sample matrix and simultaneously cooling the sampling zone. A bi-temperature-controlled (BTC) system,
allowing 10 mL of test sample heating and headspace external-cooling, was employed for the CVZ formation around the SPME-fiber
sampling area. In the CVZ procedure, the heated headspace vapor undergoes a sudden cooling near the SPME to form a dense cloud
of analyte–water vapor, which is helpful for adsorption or absorption of the analyte. The device was evaluated for the quantitative
analysis of aqueous chlorothalonil. Parameters influencing sampling efficiency, e.g., SPME fiber coating, SPME sampling temperature
and time, solution modifier, addition of salt, sample pH, and temperature, were investigated and optimized thoroughly. The
proposed BTC-HS-SPME method afforded a best extraction efficiency of above 94% accuracy (less than 4.1% RSD, n = 7) by using the PDMS fiber to collect chlorothalonil in the headspace at 5 °C under the optimized condition, i.e., heating
sample solution (added as 10% ethylene glycol and 30% NaCl, at pH 7.0) at 130 °C for 15 min. The detection was linear from
0.01 to 80 μg L−1 with a regression coefficient of 0.9998 and had a detection limit of 3.0 ng L−1 based on S/N = 3. Practical application was demonstrated by analyzing chlorothalonil in farm water samples with promising
results and recoveries. The approach provided a very simple, fast, sensitive, and solvent-free procedure to collect analytes
from aqueous solution. The approach can provide a new platform for other sensitive HS-SPME assays. 相似文献
3.
Habib Bagheri Alireza Akbarinejad Ali Aghakhani 《Analytical and bioanalytical chemistry》2014,406(8):2141-2149
A high-temperature-resistant solid-phase microextraction (SPME) fiber was prepared based on polyetherimide (PEI) by the electrospinning method. The PEI polymeric solution was converted to nanofibers using high voltages and directly coated on a stainless steel SPME needle. The scanning electron microscopy images of PEI coating showed fibers with diameter range of 500–650 nm with a homogeneous and smooth surface morphology. The SPME nanofibers coating was optimized for PEI percentage, electrospinning voltage, and time. The extraction efficiency of the coating was investigated for headspace SPME of some environmentally important polycyclic aromatic hydrocarbons from aqueous samples followed by gas chromatography–mass spectrometry measurement. In addition, the important extraction parameters including extraction temperature, extraction time, ionic strength, as well as desorption temperature and time were investigated and optimized. The detection limits of the method under optimized conditions ranged from 1 to 5 ng L?1 using time-scheduled selected ion monitoring mode. The relative standard deviations of the method were between 1.1 and 7.1 %, at a concentration level of 500 ng L?1. The calibration curves of polycyclic aromatic hydrocarbons showed linearity in the range of 5–1000 ng L?1. The developed method was successfully applied to real water samples and the relative recovery percentages obtained from the spiked water samples were from 84 to 98 % for all the selected analytes except for acenaphthene which was from 75 to 106 %. 相似文献
4.
López-Darias J Anderson JL Pino V Afonso AM 《Analytical and bioanalytical chemistry》2011,401(9):2965-2976
Two solid-phase microextraction (SPME) sorbent coatings based on polymeric ionic liquids (PILs) have been utilized for the
analysis of complex coffee aroma samples. The PIL-based SPME coatings examined, namely, poly(1-(4-vinylbenzyl)-3-hexadecylimidazolium
bis[(trifluoromethyl)sulfonyl]imide) [poly(VBHDIm+ NTf2−)], with ∼14-μm thickness, and poly(1-vinyl-3-hexylimidazolium chloride) [poly(ViHIm+ Cl−)], with ∼8-μm thickness, were employed for the headspace determination of up to 49 analytes from four different coffee beans:
two French roast coffees of different brands, Sumatra coffee, and decaffeinated Sumatra coffee. The analysis was conducted
using gas chromatography coupled to mass spectrometry. For comparative purposes, the commercial polyacrylate (PA, 85-μm film
thickness) SPME coating was utilized under the same extraction conditions. The three SPME coatings tested behaved quite differently
as a function of the families of compounds extracted. Thus, the poly(VBHDIm+ NTf2−) coating was extremely selective for aldehydes while also exhibiting good extraction efficiencies for acids. The poly-(ViHIm+ Cl−) coating exhibited superior performance for aromatic alcohols, and the PA coating worked better for heterocyclic aromatics.
Both PIL-based SPME sorbent coatings demonstrated exceptional selectivity and extraction efficiency when dealing with complex
coffee aromas in spite of their small film thicknesses. 相似文献
5.
A new solid phase microextraction (SPME) fiber based on high-temperature silicone glue coated on a stainless steel wire is presented. The fiber coating can be prepared easily in a few minutes, it is mechanically stable and exhibits relatively high thermal stability (up to 260 °C). The extraction properties of the fiber to benzene, toluene, ethylbenzene, and xylenes (BTEX) were examined using both direct and headspace SPME modes coupled to gas chromatography-flame ionization detection. The effects of the extraction and desorption parameters including extraction and desorption time, sampling and desorption temperature, and ionic strength on the extraction/desorption efficiency have been studied. For both headspace and direct SPME the calibration graphs were linear in the concentration range from 0.5 μg L−1 to 10 mg L−1 (R2 > 0.996) and detection limits ranged from 0.07 to 0.24 μg L−1. Single fiber repeatability and fiber-to-fiber reproducibility were less than 6.8 and 21.5%, respectively. Finally, headspace SPME was applied to determine BTEX in petrol station waste waters with spiked recoveries in the range of 89.7-105.2%. 相似文献
6.
Solid phase microextraction of volatile organic compounds using carboxen-polydimethylsiloxane fibers
Summary A new 80 μm Carboxen-polydimethylsiloxane (PDMS) fiber for solid phase microextraction (SPME) was tested for the enrichment
of volatile organic compounds from water and air. Detection limits between 13 ng L−1 (CH2Cl2) and 0.1 ng L−1 (CHCl2Br and CHClBr2) for the combination: Carboxen-PDMS fiber and GC-ECD and between 35 ng L−1 and 45 ng L−1 (BTEX compounds) for the combination: Carboxen-PDMS and GC-FID using the headspace procedure were determined. Comparisons
with the 100 μm PDMS fiber and further coatings show the advantages of the Carboxen-PDMS fiber with respect to extraction
efficiency. Disadvantages of the new fiber compared with the 100 μm PDMS fiber are poorer repeatability and prolongation of
equilibrium time. Distribution coefficients of the BTEX compounds between aqueous solution and SPME fiber coating were calculated
and compared with the results of other researchers and with octanol-water partition coefficients. 相似文献
7.
A novel cedar-like Au nanoparticles (AuNPs) coating was fabricated on an etched stainless steel (SS) wire by direct chemical deposition and used as an efficient and unbreakable solid phase microextraction (SPME) fiber. The etched SS wire offers a rough surface structure for subsequent growth of AuNPs in chloroauric acid solution. As a result, the uniform cedar-like AuNPs coating with larger surface area was tightly attached to the etched SS wire substrate. The AuNPs coated etched SS fiber (AuNPs/SS) was examined for SPME of ultraviolet (UV) filters, phthalate esters and aromatic hydrocarbons coupled to high-performance liquid chromatography with UV detection. The fabricated fiber exclusively exhibited excellent extraction efficiency and selectivity for some aromatic hydrocarbons. Influential parameters of extraction and desorption time, temperature, stirring rate and ionic strength were investigated and optimized. The limits of detection ranged from 0.008 μg L−1 to 0.037 μg L−1. The single fiber repeatability varied from 3.90% to 4.50% and the fiber-to-fiber reproducibility ranged from 5.15% to 6.87%. The recovery of aromatic hydrocarbons in real water samples spiked at 2.0 μg L−1 and 20 μg L−1 ranged from 94.38% to 106.2% with the relative standard deviations below 6.44%. Furthermore the growth of the cedar-like AuNPs coating can be performed in a highly reproducible manner. This fabricated fiber exhibits good stability and withstands at least 200 extraction and desorption replicates. 相似文献
8.
Stoichev T Baptista MS Basto MC Carvalho PN Vasconcelos MT 《Analytical and bioanalytical chemistry》2008,391(1):425-432
In order to survey the influence of estrogenic compounds on cyanobacteria, solid-phase microextraction (SPME) with a carbowax-divinylbenzene
fibre was used for the determination of tert-octylphenol (tert-OP), n-nonylphenol (n-NP), technical nonylphenol (tech-NP) and bisphenol A (BPA) in cyanobacteria culture media by gas chromatography
with flame ionization detection. Determinations were carried out without derivatization in deionized water and filtered culture
media. A comparison between f2 and Fraquil culture media was performed, which showed that only f2 allowed quantitative recoveries.
Headspace SPME with salting out, requiring only 10 mL of sample, was suitable for tert-OP, n-NP, and tech-NP determination
with limits of detection (LOD) of <0.05 μg L−1. For BPA, direct immersion SPME could provide a LOD of 1 μg L−1. Automated sampling allowed reproducible extraction. No exudate substances overlapped with the studied compounds during the
chromatographic separation and no matrix effects were observed. Ecotoxicity tests can be performed by single spiking of tert-OP
and tech-NP and multiple spiking of n-NP due to its lower stability. 相似文献
9.
5,11,17,23-Tetra-tert-butyl-25,27-dihydroxy-26,28-diglycidyloxycalix[4]arene (diglycidyloxy-C[4]) has been synthesized and used for preparation of a sol-gel solid-phase microextraction fiber with enhanced extraction efficiency. The sol-gel procedure was developed using a sol solution containing diglycidyloxy-C[4] as organic component and both tetraethoxysilane and 3-aminopropyltriethoxysilane (KH-550) as precursors. No additional catalysts were used and no centrifugation was performed. Diglycidyloxy-C[4] was highly chemically reactive toward KH-550 even at room temperature, which increased the calixarene content of the coating, simplified the sol-gel procedure, reduced the sol-gel reaction time, enhanced the polarity of the coating, and improved extraction performance. The sol-gel mixture also had very good coating properties and was highly uniformly distributed on the surface of the fiber; because of these characteristics several fibers could be prepared from one sol-gel solution. Efficient extraction of trace analytes (µg L?1 levels) from aqueous samples was accomplished using this kind of new fiber. Very low detection limits (ng L?1 level) were achieved for most polar (aromatic amines and phenols) and nonpolar (polycyclic aromatic hydrocarbons) aromatic compounds by SPME followed by gas chromatography with flame ionization detection. The new coating had excellent solvent and thermal (350 °C) stability. Lifespan was also good—a fiber could be used more than 300 times in headspace SPME without substantial changes in the properties of the coating. 相似文献
10.
A simple and reliable method has been established for determination of cis and trans-1,3-dichloropropene (1,3-DCP) in water by headspace solid-phase microextraction (HS-SPME) then GC–ECD. An experimental design
with two steps was performed to determine the best experimental conditions for extraction of the 1,3-DCP isomers. First, a
26−2 fractional factorial design was conducted to screen for significant conditions. Second, a central composite design (CCD)
was performed to optimise the variables. The best experimental extraction conditions were: polydimethylsiloxane–divinylbenzene
(PDMS–DVB)-coated fibre, 20-min extraction time, 12 °C extraction temperature, 300 g L−1 NaCl, and 20 mL headspace volume in 40-mL vial. Under these conditions the method detection limit (MDL) was 0.5 ng L−1 for cis-1,3-DCP and 1.0 ng L−1 for trans-1,3-DCP. The method quantification limit (MQL) was 1.2 ng L−1 for cis-1,3-DCP and 3.0 ng L−1 for trans-1,3-DCP. For both isomers the relative standard deviation (RSD) for analysis of 50 ng L−1 or 0.5 μg L−1 of the isomer mixture was less than 8%. When the proposed method was applied to surface (river) water and tapwater samples
from Gipuzkoa province (Spain) the target analytes were not detected. The method was also used to investigate the presence
of the isomers in leachates from agricultural soil. A mixed solution was added to samples of two different soils and 1,3-DCP
isomers were quantified in leachate obtained from the samples. 相似文献
11.
Homeira Ebrahimzadeh Ali Mehdinia Yadollah Yamini Saeed Kasraee Amir Gholizade 《International journal of environmental analytical chemistry》2013,93(13):963-975
Nano-structured polypyrrole (PPY) was used as a coating of solid-phase microextraction (SPME) fibre to increase the extraction efficiency of headspace solid phase microextraction (HS-SPME) of mono-nitrotoluene (MNT) isomers in water samples. The nano-structured PPY was prepared electrochemically by template-free method in the presence of dodecylbenzene sulphonate (DBS) as dopant. Nano-fibrous structures of PPY with a diameter in the range of 38–129 nm were obtained. The porous surface structure of the film, revealed by scanning electron microscopy (SEM), provided high surface areas and allowed for high extraction efficiency of MNT isomers. The extraction procedure was optimised by selecting the appropriate extraction parameters including the time and temperature of adsorption, salt concentration and stirring rate. The calibration graphs obtained by HS-SPME using the proposed fibre followed by GC-FID analysis were linear in a concentration range of 0.1–500 µg L?1 (r > 0.999) with detection limits below 0.012 µg L?1 for three isomers. Repeatability of the method was less than 6% (RSD%, n = 4). Good recoveries (88–108%) were obtained for the extraction of mono-nitrotoluenes in real water samples. 相似文献
12.
Solid-phase microextraction coupled with microcolumn liquid chromatography for the analysis of amitriptyline in human urine 总被引:1,自引:0,他引:1
Summary Solid-phase microextraction (SPME) is a solvent-free sample-preparation technique that enables isolation and pre-concentration
of analytes from a sample on a thin film coating a fused-silica fiber. In this study SPME coupled with microcolumn liquid
chromatography (micro LC) has been used for the determination of four tricyclic antidepressants (amitriptyline, imipramine,
nortriptyline, and desipramine) in human urine. SPME conditions which affect extraction efficiency were optimized, and under
the optimum conditions the system was a few hundred times more sensitive than direct LC analysis without SPME. For amitriptyline
the detection limit was 3 ng mL−1 and the calibration curve was linear in the range of 5–500 ng mL−1. The SPME-micro LC method has been applied to the analysis of amitriptyline in patient’s urine. 相似文献
13.
A piece of fused-silica fibre coated with silica modified with ketamine-groups was used as a solidphase microextraction (SPME)
fibre and its efficiency in the qualitative and quantitative analysis of volatile organic compounds released from coloured
overprinting on DVDs was evaluated. The effect of the parameters that can affect the SPME procedure, such as extraction time,
extraction temperature, desorption temperature, was investigated to determine the analytical performance of this novel fibre
in the qualitative and quantitative analyses of organic compounds. The optimised procedure was applied to the qualitative
and quantitative analyses of organic compounds released from coloured overprinting on DVDs. The limit of detection of 4-methoxyphenol
(mequinol) was 88 × 10−3 μg mL−1, while the limit of quantification (LOQ) was calculated as ten times the baseline noise, i.e. 3.1 × 10−1 μg mL−1. The proposed fibre was used successfully for preconcentration of the volatile organic compounds from the gaseous phase of
DVD samples. 相似文献
14.
Microwave-assisted thermal desorption (MAD) coupled to headspace solid-phase microextraction (HS-SPME) has been studied for
in-situ, one-step, sample preparation for PAHs collected on XAD-2 adsorbent, before gas chromatography with mass spectrometric
detection. The PAHs on XAD-2 were desorbed into the extraction solution, evaporated into the headspace by use of microwave
irradiation, and absorbed directly on a solid-phase microextraction fiber in the headspace. After desorption from the SPME
fiber in the hot GC injection port, PAHs were analyzed by GC–MS. Conditions affecting extraction efficiency, for example extraction
solution, addition of salt, stirring speed, SPME fiber coating, sampling temperature, microwave power and irradiation time,
and desorption conditions were investigated. Experimental results indicated that extraction of 275 mg XAD-2, containing 10–200 ng
PAHs, with 10-mL ethylene glycol–1 mol L−1 NaCl solution, 7:3, by irradiation with 120 W for 40 min (the same as the extraction time), and collection with a PDMS–DVB
fiber at 35 °C, resulted in the best extraction efficiency. Recovery was more than 80% and RSD was less than 14%. Optimum
desorption was achieved by heating at 290 °C for 5 min. Detection limits varied from 0.02 to 1.0 ng for different PAHs. A
real sample was obtained by using XAD-2 to collect smoke from indoor burning of joss sticks. The amounts of PAHs measured
varied from 0.795 to 2.53 ng. The method is a simple and rapid procedure for determination of PAHs on XAD-2 absorbent, and
is free from toxic organic solvents. 相似文献
15.
A fully automated method using direct immersion solid-phase microextraction (DI-SPME) and headspace on-fiber silylation for
simultaneous determinations of exogenous endocrine-disrupting chemicals (EDCs) and endogenous steroid hormones in environmental
aqueous and biological samples by gas chromatography–mass spectrometry (GC-MS) was developed and compared to a previously
reported manual method. Three EDCs and five endocrine steroid hormones were selected to evaluate this method. The extraction
and derivatization time, ion strength, pH, incubation temperature, sample volume, and extraction solvent were optimized. Satisfactory
results in pure water were obtained in terms of linearity of calibration curve (R
2=0.9932–1.0000), dynamic range (3 orders of magnitude), precision (4–9% RSD), as well as LOD (0.001–0.124 μg L−1) and LOQ (0.004–0.413 μg L−1), respectively. These results were similar to those obtained using a manual method, and moreover, the precision was improved.
This new automated method has been applied to the determinations of target compounds in real samples used in our previous
study on a manual SPME method. Exogenous octylphenol (OP), technical grade nonylphenol (t-NP), and diethylstilbestrol (DES) were at 0.13, 5.03, and 0.02 μg L−1 in river water and 3.76, 13.25, and 0.10 μg L−1 in fish serum, respectively. Natural steroid hormones estrone (E1), 17β-estradiol (E2), and testosterone (T) were at 0.19, 0.11, and 6.22 μg L−1 in river water; and in female fish serum E1, E2, and pregnenolone (PREG) were at 1.37, 1.95, and 6.25 μg L−1, respectively. These results were confirmed by the manual method. The developed fully automated SPME and on-fiber silylation
procedures showed satisfactory applications in environmental analysis and the performances show improved precision and a reduced
analysis time compared to the manual method. 相似文献
16.
Noushin Rastkari Reza Ahmadkhaniha Masud Yunesian 《International journal of environmental analytical chemistry》2013,93(14):1650-1665
A reliable and sensitive method for simultaneous determination of perchloroethylene (PCE), trichloroethylene (TCE), and trichloroacetic acid (TCA) in human urine by gas chromatography-mass spectrometry (GC/MS) is described after extraction and preconcentration by a new solid-phase microextraction (SPME) adsorbent. The potential of single-walled carbon nanotubes (SWCNTs) as SPME adsorbent for the pre-concentration of environmental pollutants has been investigated in recent years. This work was carried out to investigate the feasibility of SWCNTs as a headspace SPME adsorbent for the determination of chloroethylenes in human urine. SWCNTs were attached onto a stainless steel wire through an organic binder. Potential factors affecting the extraction efficiency, including extraction time, extraction temperature, desorption time, desorption temperature, and salinity were optimized. The developed method showed good performance. For PCE and TCE, calibration curves were linear (r 2 ?≥?0.994) over the concentration ranges from 15 to 8000?ng?L?1 and the limit of detection (LOD) at signal-to-noise (S/N) ratio of 3 was 5?ng?L?1. The analytical procedure also involves derivatization of TCA with dimethyl sulfate, before headspace sampling. For TCA the linear range and LOD were 45-8000 (r 2 ?≥?0.992) and 15?ng L?1, respectively. In addition, a comparative study between the SWCNT and a commercial carboxen/polydimethylsiloxane (CAR/PDMS) SPME fibre for the determination of chloroethylenes in human urine was carried out. SWCNT fibre showed higher extraction capacity, better thermal stability (over 350°C) and longer life span (over 200 times) than the commercial CAR/PDMS fibre. The developed method was successfully applied to determine chloroethylenes in human urine samples. As the results indicated, the mean concentrations of TCE, PCE and TCA in exposed workers (dry-cleaning industry workers) were significantly greater than that of control group. 相似文献
17.
Based on polyethylene glycol modified single-walled carbon nanotubes, a novel sol–gel fiber coating was prepared and applied
to the headspace microextraction of chlorinated organic carriers (COCs) in textiles by gas chromatography-electron capture
detection. The preparation of polyethylene glycol modified single-walled carbon nanotubes and the sol–gel fiber coating process
was stated and confirmed by infrared spectra, Raman spectroscopy, and scanning electron microscopy. Several parameters affecting
headspace microextraction, including extraction temperature, extraction time, salting-out effect, and desorption time, were
optimized by detecting 11 COCs in simulative sweat samples. Compared with the commercial solid-phase microextraction fibers,
the sol–gel polyethylene glycol modified single-walled carbon nanotubes fiber showed higher extraction efficiency, better
thermal stability, and longer life span. The method detection limits for COCs were in the range from 0.02 to 7.5 ng L−1 (S/N = 3). The linearity of the developed method varied from 0.001 to 50 μg L−1 for all analytes, with coefficients of correlation greater than 0.974. The developed method was successfully applied to the
analysis of trace COCs in textiles, the recoveries of the analytes indicated that the developed method was considerably useful
for the determination of COCs in ecological textile samples. 相似文献
18.
de Morais P Stoichev T Basto MC Carvalho PN Vasconcelos MT 《Analytical and bioanalytical chemistry》2011,399(7):2531-2538
A headspace solid phase microextraction coupled to gas chromatography with electron capture detector (HS-SPME-GC-ECD) method
was optimized for the determination of seven chlorophenols (CPs) with different levels of chlorination. This is the first
time that HS-SPME-GC-ECD with acetylation of the analytes is used for the simultaneous determination of CPs in water samples.
The influence of fibre type, derivatization conditions, salt addition, temperature and time of extraction and temperature
of desorption was checked. Possible sources of contamination and analyte losses were considered. The best results were obtained
with the polydimethylsiloxane/divinylbenzene fibre, derivatization by acetylation using 100 μL of acetic anhydride and 0.1 g
of anhydrous sodium carbonate per 10 mL of sample, salt addition of 100 g L−1 sodium chloride, extraction at 70 °C for 60 min and desorption in the GC injector at 260 °C for 6 min. The limits of detection
(LOD) for monochlorophenols were 12 and 122 ng L−1 for 2-chlorophenol and 4-chlorophenol, respectively. For polychlorinated CPs, the LODs were lower than 6 ng L−1, values similar to the existing methods that use SPME with derivatization for CPs determination in water samples. The method
is suitable for the determination of CPs in most environmental aqueous samples. Repeatability and reproducibility were less
than 16.8% and 11.7%, respectively. The optimized method was successfully applied for the analysis of waters with complex
matrices such as river and estuarine water samples. 相似文献
19.
Lijun Xie Shuqin LiuZhubing Han Ruifen JiangHong Liu Fang Zhu Feng ZengChengyong Su Gangfeng Ouyang 《Analytica chimica acta》2015
Metal-organic frameworks (MOFs) have received great attention as novel sorbents due to their fascinating structures and intriguing potential applications in various fields. In this work, a MIL-101(Cr)-coated solid-phase microextraction (SPME) fiber was fabricated by a simple direct coating method and applied to the determination of volatile compounds (BTEX, benzene, toluene, ethylbenzene, m-xylene and o-xylene) and semi-volatile compounds (PAHs, polycyclic aromatic hydrocarbons) from water samples. The extraction and desorption conditions of headspace SPME (HS-SPME) were optimized. Under the optimized conditions, the established methods exhibited excellent extraction performance. Good precision (<7.7%) and low detection limits (0.32–1.7 ng L−1 and 0.12–2.1 ng L−1 for BTEX and PAHs, respectively) were achieved. In addition, the MIL-101(Cr)-coated fiber possessed good thermal stability, and the fiber can be reused over 150 times. The fiber was successfully applied to the analysis of BTEX and PAHs in river water by coupling with gas chromatography–mass spectrometry (GC–MS). The analytes at low concentrations (1.7 and 10 ng L−1) were detected, and the recoveries obtained with the spiked river water samples were in the range of 80.0–113% and 84.8–106% for BTEX and PAHs, respectively, which demonstrated the applicability of the self-made fiber. 相似文献
20.
Reddithota J. Krupadam Bhagyashree Bhagat Muntazir S. Khan 《Analytical and bioanalytical chemistry》2010,397(7):3097-3106
A method based on solid--phase extraction with a molecularly imprinted polymer (MIP) has been developed to determine five
probable human carcinogenic polycyclic aromatic hydrocarbons (PAHs) in ambient air dust by gas chromatography-mass spectrometry
(GC-MS). Molecularly imprinted poly(vinylpyridine-co-ethylene glycol dimethacrylate) was chosen as solid-phase extraction
(SPE) material for PAHs. The conditions affecting extraction efficiency, for example surface properties, concentration of
PAHs, and equilibration times were evaluated and optimized. Under optimum conditions, pre-concentration factors for MIP-SPE
ranged between 80 and 93 for 10 mL ambient air dust leachate. PAHs recoveries from MIP-SPE after extraction from air dust
were between 85% and 97% and calibration graphs of the PAHs showed a good linearity between 10 and 1000 ng L−1 (r = 0.99). The extraction efficiency of MIP for PAHs was compared with that of commercially available SPE materials—powdered
activated carbon (PAC) and polystyrene-divinylbenzene resin (XAD)—and it was shown that the extraction capacity of the MIP
was better than that of the other two SPE materials. Organic matter in air dust had no effect on MIP extraction, which produced
a clean extract for GC-MS analysis. The detection limit of the method proposed in this article is 0.15 ng L−1 for benzo[a]pyrene, which is a marker molecule of air pollution. The method has been applied to the determination of probable carcinogenic
PAHs in air dust of industrial zones and satisfactory results were obtained. 相似文献