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waterpipe, water-pipe, nargile, narghile, arguileh, arguile, shisha, sheesha, chichi, hubble bubble, hubbly bubbly, goza, hookah, bong
| Title | Pub Year | Author Sort descending | SearchLink |
|---|---|---|---|
| A novel graphene nanosheets coated stainless steel fiber for microwave assisted headspace solid phase microextraction of organochlorine pesticides in aqueous samples followed by gas chromatography with electron capture detection | 2011 | Department of Chemistry, National Chung-Hsing University, Taichung 402, Taiwan. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
28-Sep
Volume
1218
Issue
39
Start Page
6861
Other Pages
6868
Notes
CI: Copyright (c) 2011; JID: 9318488; 0 (Hydrocarbons, Chlorinated); 0 (Pesticides); 0 (Water Pollutants, Chemical); 12597-68-1 (Stainless Steel); 7782-42-5 (Graphite); 2011/04/15 [received]; 2011/08/08 [revised]; 2011/08/08 [accepted]; 2011/08/16 [aheado
Place of Publication
Netherlands
ISSN/ISBN
1873-3778; 0021-9673
Accession Number
PMID: 21872868
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1016/j.chroma.2011.08.019 [doi]
Output Language
Unknown(0)
PMID
21872868
Abstract
In this study, a novel graphene nanosheets (GNSs) coated solid phase microextraction (SPME) fiber was prepared by immobilizing microwave synthesized GNSs on a stainless steel wire. Microwave synthesized GNSs were verified by X-ray diffraction, field emission-scanning electron microscopy (FE-SEM) and transmission electron microscope (TEM). GNS-SPME fiber was characterized using FE-SEM and the results showed the GNS coating was homogeneous, porous, and highly adherent to the surface of the stainless steel fiber. The performance and feasibility of the GNS-SPME fiber was evaluated under one-step microwave assisted (MA) headspace (HS) SPME followed by gas chromatography with electron capture detection for five organochlorine pesticides (OCPs) in aqueous samples. Parameters influencing the extraction efficiency of MA-HS-GNS-SPME such as microwave irradiation power and time, pH, ionic strength, and desorption conditions were thoroughly examined. Under the optimized conditions, detection limits for the OCPs varied between 0.16 and 0.93 ng L(-1) and linear ranges varied between 1 and 1500 n gL(-1), with correlation coefficients ranging from 0.9984 to 0.9998, and RSDs in the range of 3.6-15.8% (n=5). In comparison with the commercial 100 mum polydimethylsiloxane fiber, the GNS coated fiber showed better extraction efficiency, higher mechanical and thermal stability (up to 290 degrees C), longer life span (over 250 times), and lower production cost. The method was successfully applied to the analysis of real water samples with recoveries ranged between 80.1 and 101.1% for river water samples. The results demonstrated that the developed MA-HS-GNS-SPME method was a simple, rapid, efficient pretreatment and environmentally friendly procedure for the analysis of OCPs in aqueous samples.
Descriptors
Links
Book Title
Database
Publisher
Elsevier B.V
Data Source
Authors
Ponnusamy,V.K., Jen,J.F.
Original/Translated Title
URL
Date of Electronic
20110816
PMCID
Editors
|
|||
| Development of liquid phase microextraction based on manual shaking and ultrasound-assisted emulsification method for analysis of organochlorine pesticides in aqueous samples | 2011 | Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
23-Dec
Volume
1218
Issue
51
Start Page
9142
Other Pages
9148
Notes
LR: 20151119; CI: Copyright (c) 2011; JID: 9318488; 0 (Emulsions); 0 (Fatty Alcohols); 0 (Hydrocarbons, Chlorinated); 0 (Pesticides); 0 (Water Pollutants, Chemical); 451W47IQ8X (Sodium Chloride); 89V4LX791F (n-decyl alcohol); 2011/09/28 [received]; 2011/1
Place of Publication
Netherlands
ISSN/ISBN
1873-3778; 0021-9673
Accession Number
PMID: 22099225
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1016/j.chroma.2011.10.084 [doi]
Output Language
Unknown(0)
PMID
22099225
Abstract
A novel method using sample preparation method, "ultrasound-assisted emulsification microextraction" (USAEME) with manual shaking, coupled with gas chromatography using and an electron capture detector (GC-ECD) was developed for the analysis of organochlorine pesticides (OCPs) in aqueous samples. The apparatus is simple and easy to operate. After manual shaking for 10s, ultrasound was used to accelerate emulsification of the organic solvent (1-decanol) in aqueous solution. Only 10 muL of the low-toxicity extraction solvent is used in this method; no dispersive solvent is required and the total extraction time is approximately 4 min. Manual shaking before ultrasound-assisted emulsification enhances the extraction efficiency by >100%. The effects of horizontal and vertical orientation as well as the location of the sample within the ultrasonic bath were studied. After centrifugation, we used an improved solvent collection system (ISCS) to reduce the amount of extraction solvent required. A 1 muL sample of the extract was injected into the GC column. Under optimum conditions, the linear range of the method is 5-2500 ngL(-1) for most of the OCPs, and the limit of detection of the method ranged from 0.6 to 2.9 ngL(-1).The relative recoveries ranged from 75 to 107% for sea water and from 70 to 99% for field fresh water. The method, which provides good enrichment factors, low LODs and minimization of the consumption of organic solvent, provides a rapid, simple and environment-friendly procedure for determining OCPs in aqueous samples.
Descriptors
Links
Book Title
Database
Publisher
Elsevier B.V
Data Source
Authors
Wei,S.Y., Leong,M.I., Li,Y., Huang,S.D.
Original/Translated Title
URL
Date of Electronic
20111103
PMCID
Editors
|
|||
| Water with low concentration of surfactant in dispersed solvent-assisted emulsion dispersive liquid-liquid microextraction for the determination of organochlorine pesticides in aqueous samples | 2013 | Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
26-Jul
Volume
1300
Issue
Start Page
51
Other Pages
57
Notes
CI: Copyright (c) 2013; JID: 9318488; 0 (Acetates); 0 (Hydrocarbons, Chlorinated); 0 (Pesticides); 0 (Polysorbates); 0 (Solvents); 0 (Surface-Active Agents); 0 (Water Pollutants, Chemical); 178A96NLP2 (Dodecanol); 76J36KE44B (lauryl acetate); OTO: NOTNLM;
Place of Publication
Netherlands
ISSN/ISBN
1873-3778; 0021-9673
Accession Number
PMID: 23566919
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1016/j.chroma.2013.02.073 [doi]
Output Language
Unknown(0)
PMID
23566919
Abstract
A novel sample preparation method, "water with low concentration of surfactant in dispersed solvent-assisted emulsion dispersive liquid-liquid microextraction (WLSEME)", coupled with gas chromatography using an electron capture detector (GC-ECD) was developed for the analysis of the organochlorine pesticides (OCPs), heptachlor, alpha-endosulfan, 4,4-DDE, 2,4-DDD and endrin, in aqueous samples. A microsyringe is used to withdrew and discharge 10-12muL of the extraction solvent and 60-120muL of water as the dispersed solvent (containing 1mgL(-1), Tween 80) 4 times within 10s to form a cloudy emulsified solution in the syringe. This is then injected into an 8mL aqueous sample spiked with all above OCPs. Dodecyl acetate and 2-dodecanol were both selected as extraction solvents to optimize their conditions separately. The total extraction time was about 0.5min. Under optimum conditions, using dodecyl acetate (12muL) as extraction solvent, the linear range of the method was 10-1000ngL(-1) for all OCPs, and the the limits of detection (LODs) ranged from 1 to 5ngL(-1). The absolute recoveries and relative recoveries were from 20.8 to 43.5% and 83.2 to 109.8% for lake water, and 19.9-49.2% and 85.4-115.9% for seawater respectively. In the second method, 2-dodecanol as extraction solvent, the linear range was from 5 to 5000ngL(-1) for the target compounds, and the LODs were between 0.5 and 2ngL(-1). The absolute recoveries and relative recoveries ranged from 25.7 to 42.2% and 96.3-111.2% for sea water, and 22.4-41.9% and 90.7-107.9% for stream water. This could solve several problems, which commonly occur in ultrasound-assisted emulsification micro-extraction (USAEME), dispersive liquid-liquid micro-extraction (DLLME) and other assisted emulsification methods. These problems include analyte degradation, increased solubility of the extraction solvent and analyte, and high toxicity and large volume of the organic solvent used.
Descriptors
Links
Book Title
Database
Publisher
Elsevier B.V
Data Source
Authors
Li,Y., Chen,P.S., Huang,S.D.
Original/Translated Title
URL
Date of Electronic
20130228
PMCID
Editors
|
|||
| Determination of volatile organic compounds in water using ultrasound-assisted emulsification microextraction followed by gas chromatography | 2012 | Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of separation science
Periodical, Abbrev.
J.Sep.Sci.
Pub Date Free Form
Mar
Volume
35
Issue
6-May
Start Page
688
Other Pages
694
Notes
CI: (c) 2012; JID: 101088554; 0 (Volatile Organic Compounds); 0 (Water Pollutants, Chemical); 2011/07/12 [received]; 2011/11/27 [revised]; 2011/12/04 [accepted]; 2012/01/24 [aheadofprint]; ppublish
Place of Publication
Germany
ISSN/ISBN
1615-9314; 1615-9306
Accession Number
PMID: 22271628
Language
eng
SubFile
Evaluation Studies; Journal Article; IM
DOI
10.1002/jssc.201100610 [doi]
Output Language
Unknown(0)
PMID
22271628
Abstract
Volatile organic compounds (VOCs) are toxic compounds in the air, water and land. In the proposed method, ultrasound-assisted emulsification microextraction (USAEME) combined with gas chromatography-mass spectrometry (GC-MS) has been developed for the extraction and determination of eight VOCs in water samples. The influence of each experimental parameter of this method (the type of extraction solvent, volume of extraction solvent, salt addition, sonication time and extraction temperature) was optimized. The procedure for USAEME was as follows: 15 muL of 1-bromooctane was used as the extraction solvent; 10 mL sample solution in a centrifuge tube with a cover was then placed in an ultrasonic water bath for 3 min. After centrifugation, 2 muL of the settled 1-bromooctane extract was injected into the GC-MS for further analysis. The optimized results indicated that the linear range is 0.1-100.0 mug/L and the limits of detection (LODs) are 0.033-0.092 mug/L for the eight analytes. The relative standard deviations (RSD), enrichment factors (EFs) and relative recoveries (RR) of the method when used on lake water samples were 2.8-9.5, 96-284 and 83-110%. The performance of the proposed method was gauged by analyzing samples of tap water, lake water and river water samples.
Descriptors
Links
Book Title
Database
Publisher
WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Data Source
Authors
Leong,M.I., Huang,S.D.
Original/Translated Title
URL
Date of Electronic
20120124
PMCID
Editors
|
|||
| Low toxic dispersive liquid-liquid microextraction using halosolvents for extraction of polycyclic aromatic hydrocarbons in water samples | 2010 | Department of Chemistry, National Tsing Hua University, Sec. 2, Kung Fu Rd., 101, Hsinchu, Taiwan. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
20-Aug
Volume
1217
Issue
34
Start Page
5455
Other Pages
5461
Notes
LR: 20151119; CI: Copyright 2010; JID: 9318488; 0 (Hydrocarbons, Brominated); 0 (Hydrocarbons, Chlorinated); 0 (Hydroxides); 0 (Polycyclic Hydrocarbons, Aromatic); 0 (Potassium Compounds); 0 (Propionates); 0 (Water Pollutants, Chemical); 451W47IQ8X (Sodiu
Place of Publication
Netherlands
ISSN/ISBN
1873-3778; 0021-9673
Accession Number
PMID: 20663510
Language
eng
SubFile
Comparative Study; Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1016/j.chroma.2010.06.056 [doi]
Output Language
Unknown(0)
PMID
20663510
Abstract
A low toxic dispersive liquid-liquid microextraction (LT-DLLME) combined with gas chromatography-mass spectrometry (GC-MS) had been developed for the extraction and determination of 16 polycyclic aromatic hydrocarbons (PAHs) in water samples. In normal DLLME assay, chlorosolvent had been widely used as extraction solvents; however, these solvents are environmental-unfriendly. In order to solve this problem, we proposed to use low toxic bromosolvent (1-bromo-3-methylbutane, LD(50) 6150mg/kg) as the extraction solvent. In this study we compared the extraction efficiency of five chlorosolvents and thirteen bromo/iodo solvents. The results indicated that some of the bromo/iodo solvents showed better extraction and had much lower toxicity than chlorosolvents. We also found that propionic acid is used as the disperser solvent, as little as 50microL is effective. Under optimum conditions, the range of enrichment factors and extraction recoveries of tap water samples are ranging 372-1308 and 87-105%, respectively. The linear range is wide (0.01-10.00microgL(-1)), and the limits of detection are between 0.0003 and 0.0078microgL(-1) for most of the analytes. The relative standard deviations (RSD) for 0.01microgL(-1) of PAHs in tap water were in the range of 5.1-10.0%. The performance of the method was gauged by analyzing samples of tap water, sea water and lake water samples.
Descriptors
Chemical Fractionation/methods, Fresh Water/chemistry, Gas Chromatography-Mass Spectrometry, Hydrocarbons, Brominated/chemistry, Hydrocarbons, Chlorinated/chemistry, Hydroxides/chemistry, Polycyclic Hydrocarbons, Aromatic/analysis/isolation & purification, Potassium Compounds/chemistry, Propionates/chemistry, Sodium Chloride/chemistry, Water Pollutants, Chemical/analysis/isolation & purification
Links
Book Title
Database
Publisher
Elsevier B.V
Data Source
Authors
Leong,M. I., Chang,C. C., Fuh,M. R., Huang,S. D.
Original/Translated Title
URL
Date of Electronic
20100630
PMCID
Editors
|
|||
| Determination of organic micropollutants in rainwater using hollow fiber membrane/liquid-phase microextraction combined with gas chromatography-mass spectrometry | 2003 | Department of Chemistry, National University of Singapore, 3 Science Drive 3, Republic of Singapore 117543, Singapore. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
17-Oct
Volume
1016
Issue
1
Start Page
11
Other Pages
20
Notes
LR: 20090115; JID: 9318488; 0 (Organic Chemicals); 0 (Water Pollutants, Chemical); ppublish
Place of Publication
Netherlands
ISSN/ISBN
0021-9673; 0021-9673
Accession Number
PMID: 14601824
Language
eng
SubFile
Journal Article; IM
DOI
Output Language
Unknown(0)
PMID
14601824
Abstract
A simple and rapid liquid-phase microextraction (LPME) method using a hollow fiber membrane (HFM) in conjunction with gas chromatography-mass spectrometry (GC-MS) is presented for the quantitative determination of 16 polycyclic aromatic hydrocarbons (PAHs) and 12 organochlorine pesticides (OCPs) in rainwater samples. The LPME conditions were optimized for achieving high enrichment of the analytes from aqueous samples, in terms of hollow fiber exposure time, stirring rate, sample pH, and composition. Enrichment factors of more than 100 could be achieved within 35 min of extraction with relative standard deviations (R.S.D.s) 1.3-13.6% for PAHs and 1.7-13.8% for OCPs, respectively, over a wide range of analyte concentrations. Detection limits ranged from 0.002 to 0.047 microg l(-1) for PAHs, and from 0.013 to 0.059 microg l(-1) for OCPs, respectively. The newly developed LPME-GC-MS method has been validated for the analysis of PAHs and OCPs in rainwater samples. Extraction recoveries from spiked synthetic rainwater samples varied from 73 to 115% for PAHs and from 75 to 113% for OCPs, respectively. Real rainwater samples were analyzed using the optimized method. The concentrations of PAHs and OCPs in real rainwater samples were between 0.005-0.162, and 0.063 microg l(-1), respectively.
Descriptors
Gas Chromatography-Mass Spectrometry/methods, Organic Chemicals/analysis, Rain, Reference Standards, Reproducibility of Results, Sensitivity and Specificity, Water Pollutants, Chemical/analysis
Links
Book Title
Database
Publisher
Data Source
Authors
Basheer,C., Balasubramanian,R., Lee,H. K.
Original/Translated Title
URL
Date of Electronic
PMCID
Editors
|
|||
| Magnetic micro-solid-phase-extraction of polycyclic aromatic hydrocarbons in water | 2016 | Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore; National University of Singapore Environmental Research Institute, T-Lab Building #02-01, 5A Engineering Drive 1, Singapore 117411, Singapore.; Depa | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
1-Apr
Volume
1440
Issue
Start Page
23
Other Pages
30
Notes
CI: Copyright (c) 2016; JID: 9318488; 0 (Polycyclic Hydrocarbons, Aromatic); 0 (Water Pollutants, Chemical); 059QF0KO0R (Water); 7782-42-5 (Graphite); OTO: NOTNLM; 2015/11/22 [received]; 2016/02/14 [revised]; 2016/02/15 [accepted]; 2016/02/17 [aheadofprin
Place of Publication
Netherlands
ISSN/ISBN
1873-3778; 0021-9673
Accession Number
PMID: 26931424
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1016/j.chroma.2016.02.046 [doi]
Output Language
Unknown(0)
PMID
26931424
Abstract
A novel sorbent, magnetic chitosan functionalized graphene oxide (MCFG) was synthesized and used in the micro-solid-phase-extraction (mu-SPE) and gas chromatography-mass spectrometric (GC-MS) analysis of polycyclic aromatic hydrocarbons (PAHs) from water. Through the use of the magnetic sorbent, the mu-SPE device also functioned as a stir bar during extraction. Three types of MCFG were prepared using glutaraldehyde cross-linked chitosan and graphene oxide with different amounts of magnetic nanoparticles (Fe3O4) (0.05g, 0.07g and 0.1g). The material was characterized using Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Parameters affecting the extraction such as the type of sorbent, extraction and desorption times, volume of sample solution and type of desorption solvent were optimized. Under the most favourable conditions, the highest extraction was obtained by using the composite prepared with 0.1g of Fe3O4. For the latter material as sorbent, the linearity of the analytes was in the range of 0.01 and 100mugL(-1) for naphthalene, fluoranthene and pyrene while acenaphthylene and phenanthrene exhibited linearity in the range of 0.05 and 100mugL(-1). For fluorene and anthracene, the linearity range was from 0.01 to 50mugL(-1). The coefficients of determination (r(2)) associated with the above linear ranges were higher than 0.987. The limits of detection from GC-MS analysis of the seven PAHs were in the range 0.2-1.8ngL(-1); limits of quantification were between 0.8 and 5.9ngL(-1) while the relative standard deviations (RSDs) varied from 2.1 to 8.2%. The recoveries of the method for the compounds at spiking levels of 1 and 5mugL(-1) were in the range 67.5-106.9% with RSDs below 15%. The enrichment factors were found to be in between 67 and 302. The developed method afforded an interesting and innovative approach using MCFG as an efficient and promising sorbent.
Descriptors
Links
Book Title
Database
Publisher
Elsevier B.V
Data Source
Authors
Naing,N.N., Yau Li,S.F., Lee,H.K.
Original/Translated Title
URL
Date of Electronic
20160217
PMCID
Editors
|
|||
| Microwave assisted extraction combined with solvent bar microextraction for one-step solvent-minimized extraction, cleanup and preconcentration of polycyclic aromatic hydrocarbons in soil samples | 2013 | Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
19-Apr
Volume
1286
Issue
Start Page
9
Other Pages
15
Notes
LR: 20131121; CI: Copyright (c) 2013; JID: 9318488; 0 (Polycyclic Hydrocarbons, Aromatic); 0 (Soil); 0 (Soil Pollutants); 3FPU23BG52 (Toluene); 2012/12/13 [received]; 2013/02/21 [revised]; 2013/02/21 [accepted]; 2013/02/27 [aheadofprint]; ppublish
Place of Publication
Netherlands
ISSN/ISBN
1873-3778; 0021-9673
Accession Number
PMID: 23497848
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1016/j.chroma.2013.02.067 [doi]
Output Language
Unknown(0)
PMID
23497848
Abstract
For the first time, a novel one-step sample preparation method that combines microwave assisted extraction and solvent bar microextraction (MAE-SBME) with analysis by gas chromatography-mass spectrometry (GC-MS), was developed for the fast and efficient determination of polycyclic aromatic hydrocarbons (PAHs) in environmental soil samples. An interesting feature of the new procedure is that SBME was conducted simultaneously with MAE. Thus, the extract from the SBME could be directly and immediately analyzed by GC-MS. A separate clean up and/or preconcentration process, such as time-consuming and tedious gel permeation chromatography, solid-phase extraction, filtration, or adsorption chromatography, normally associated with conventional MAE, was not necessary. It is also notable that the procedure was environmentally benign since water was used as the extraction solvent in MAE, and only several microliters of organic solvent were used in SBME. Some factors affecting the extraction were studied and optimized. Under the most favorable conditions, the method showed good linearities (between 0.2 and 500, 0.5 and 500, 1 and 500, and 2 and 500 ng/g, depending on the analytes), low limits of detection (from 0.03 to 0.25 ng/g), and satisfactory precision (with relative standard deviations below 9.8%). The MAE-SBME procedure provides a fast and simple sample preparation approach for the processing of environmental soil samples.
Descriptors
Links
Book Title
Database
Publisher
Elsevier B.V
Data Source
Authors
Guo,L., Lee,H.K.
Original/Translated Title
URL
Date of Electronic
20130227
PMCID
Editors
|
|||
| Application of ultrasound-assisted emulsification microextraction based on applying low-density organic solvent for the determination of organochlorine pesticides in water samples | 2012 | Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
24-Aug
Volume
1252
Issue
Start Page
67
Other Pages
73
Notes
LR: 20151119; CI: Copyright (c) 2012; JID: 9318488; 0 (Hydrocarbons, Chlorinated); 0 (Octanes); 0 (Pesticides); 0 (Water Pollutants, Chemical); 451W47IQ8X (Sodium Chloride); 540-84-1 (2,2,4-trimethylpentane); 2012/04/17 [received]; 2012/06/14 [revised]; 2
Place of Publication
Netherlands
ISSN/ISBN
1873-3778; 0021-9673
Accession Number
PMID: 22771061
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1016/j.chroma.2012.06.065 [doi]
Output Language
Unknown(0)
PMID
22771061
Abstract
In this study, a polyethylene Pasteur pipette-based ultrasound-assisted emulsification microextraction (USAEME) applying low-density organic solvent was successfully developed for the extraction of trace levels of organochlorine pesticides (OCPs) in water samples and followed by gas chromatography-mass spectrometry (GC-MS) analysis. In this approach, a polyethylene Pasteur squeeze-type pipette was employed as a convenient extraction device and ultrasound radiation was applied to accelerate the emulsification of low-density organic solvent in aqueous solutions to enhance the microextraction efficiency of OCPs in water samples. Thirty microliters of extraction solvent (isooctane), of lower density than water, were injected into the aqueous sample solution held in the pipette. The latter was then immersed in an ultrasound water bath to form an emulsion. After 30s extraction, phase separation was achieved by centrifugation. The upper layer (isooctane) was collected and analyzed by GC-MS. No disperser solvent was required in this procedure. Significantly, fast analysis and high extraction efficiency were achieved. Another feature of the procedure was the use of the pipette as the extraction device, which permitted less dense than water organic solvent to be used as extraction solvent. This method broadens the applicability of USAEME to a wider range of solvent. Additionally, carry-over problems were avoided with the use of the disposable pipette. Parameters affecting the efficiency of polyethylene Pasteur pipette-based USAEME, such as the extraction solvent, extraction solvent volume, extraction and centrifugation time, ionic strength and extraction temperature were investigated. Under the optimum conditions, the proposed method provided good enrichment factors (EFs) in the range of 128 and 328, with relative standard deviations (RSDs) ranging from 2.7% to 12.4%. The limits of detection were in the range of 0.8 and 10ng/L depending on the analytes. The linearities were between 0.01 and 50mug/L for hexachlorobenzene, dieldrin, endrin and o,p'-DDD, 0.05-25mug/L for heptachlor, and 0.005-50mug/L for p,p'-DDE. Finally, the polyethylene Pasteur pipette-based USAEME was successfully used for the fast determination of OCPs in river and tap water samples. The proposed method provides a simple, convenient, rapid, sensitive, cost-effective, and environmentally friendly process for the determination of OCPs in water samples.
Descriptors
Links
Book Title
Database
Publisher
Elsevier B.V
Data Source
Authors
Zhang,Y., Lee,H.K.
Original/Translated Title
URL
Date of Electronic
20120626
PMCID
Editors
|
|||
| Electro membrane extraction followed by low-density solvent based ultrasound-assisted emulsification microextraction combined with derivatization for determining chlorophenols and analysis by gas chromatography-mass spectrometry | 2012 | Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore. | Read more... |
|
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of chromatography.A
Periodical, Abbrev.
J.Chromatogr.A
Pub Date Free Form
22-Jun
Volume
1243
Issue
Start Page
14
Other Pages
22
Notes
LR: 20131121; CI: Copyright (c) 2012; JID: 9318488; 0 (Chlorophenols); 0 (Emulsions); 0 (Membranes, Artificial); 0 (Water Pollutants, Chemical); 059QF0KO0R (Water); NV1779205D (1-Octanol); 2012/03/01 [received]; 2012/04/23 [revised]; 2012/04/23 [accepted]
Place of Publication
Netherlands
ISSN/ISBN
1873-3778; 0021-9673
Accession Number
PMID: 22579488
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1016/j.chroma.2012.04.054 [doi]
Output Language
Unknown(0)
PMID
22579488
Abstract
A highly efficient and simple two-step method, electro membrane extraction (EME) followed by low-density solvent based ultrasound-assisted emulsification microextraction (EME-LDS-USAEME) combined with derivatization and analysis by gas chromatography-mass spectrometry (GC-MS), was developed for the determination of trace level chlorophenols in environmental water samples. In the first step, the analytes were extracted, under electrical potential, from the sample solution into the acceptor solution, which was held in a polypropylene membrane sheet with 1-octanol as the supported liquid membrane. The acceptor solution from the first step was then employed as the sample solution for the second step of LDS-USAEME. In this step, the target analytes were extracted into a solvent with lower density than water that was dispersed in the sample solution with the assistance of ultrasound. The extract was separated from the sample solution by centrifugation and collected as the upper layer. Finally, the extract with a derivatization reagent were injected into a GC-MS system for analysis. Six chlorophenols, 2-chlorophenol, 4-chlorophenol, 2,3-dichlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol were selected here as model compounds for developing and evaluating the method. Several factors influencing the extraction and derivatization were investigated. With the EME-LDS-USAEME procedure, high enrichment factors of up to 2198 were achieved. Under the most favorable conditions, good limits of detection (down to 0.005 mug/L), linearity (from 0.05-10 to 0.2-10 mug/L, depending on the analytes), and repeatability of extraction (RSDs below 9.7%, n=5) were obtained. The proposed method was applied to determine chlorophenols in drainwater samples.
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Elsevier B.V
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Authors
Guo,L., Lee,H.K.
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Date of Electronic
20120501
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