101
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Application of SPME to the determination of alkylphenols and bisphenol A in cyanobacteria culture media. Anal Bioanal Chem 2008; 391:425-32. [DOI: 10.1007/s00216-008-2005-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Revised: 02/08/2008] [Accepted: 02/20/2008] [Indexed: 10/22/2022]
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102
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Middelthon-Bruer TM, Gjelstad A, Rasmussen KE, Pedersen-Bjergaard S. Parameters affecting electro membrane extraction of basic drugs. J Sep Sci 2008; 31:753-9. [DOI: 10.1002/jssc.200700502] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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103
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Pedersen-Bjergaard S, Rasmussen KE. Liquid-phase microextraction with porous hollow fibers, a miniaturized and highly flexible format for liquid–liquid extraction. J Chromatogr A 2008; 1184:132-42. [PMID: 17889886 DOI: 10.1016/j.chroma.2007.08.088] [Citation(s) in RCA: 353] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Revised: 08/24/2007] [Accepted: 08/31/2007] [Indexed: 11/16/2022]
Abstract
Since 1999, substantial research has been devoted to the development of liquid-phase microextraction (LPME) based on porous hollow fibers. With this technology, target analytes are extracted from aqueous samples, through a thin supported liquid membrane (SLM) sustained in the pores in the wall of a porous hollow fiber, and further into a microL volume of acceptor solution placed inside the lumen of the hollow fiber. After extraction, the acceptor solution is directly subjected to a final chemical analysis by liquid chromatography (HPLC), gas chromatography (GC), capillary electrophoresis (CE), or mass spectrometry (MS). In this review, LPME will be discussed with focus on extraction principles, historical development, fundamental theory, and performance. Also, major applications have been compiled, and recent forefront developments will be discussed.
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104
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Sun SH, Xie JP, Xie FW, Zong YL. Determination of volatile organic acids in oriental tobacco by needle-based derivatization headspace liquid-phase microextraction coupled to gas chromatography/mass spectrometry. J Chromatogr A 2008; 1179:89-95. [PMID: 18155225 DOI: 10.1016/j.chroma.2007.11.102] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Revised: 11/26/2007] [Accepted: 11/28/2007] [Indexed: 10/22/2022]
Abstract
A method coupling needle-based derivatization headspace liquid-phase microextraction with gas chromatography-mass spectrometry (HS-LPME/GC-MS) was developed to determine volatile organic acids in tobacco. The mixture of N,O-bis(trimethylsilyl)trifluoroacetamide and decane was utilized as the solvent for HS-LPME, resulting that extraction and derivatization were simultaneously completed in one step. The solvent served two purposes. First, it pre-concentrated volatile organic acids in the headspace of tobacco sample. Second, the volatile organic acids extracted were derivatized to form silyl derivatives in the drop. The main parameters affecting needle-based derivatization HS-LPME procedure such as extraction and derivatization reagent, microdrop volume, extraction and derivatization time, and preheating temperature and preheating time were optimized. The standard addition approach was essential to obtain accurate measurements by minimizing matrix effects. Good linearity (R(2)> or =0.9804) and good repeatability (RSDs< or =15.3%, n=5) for 16 analytes in spiked standard analytes sample were achieved. The method has the additional advantages that at the same time it is simple, fast, effective, sensitive, selective, and provides an overall profile of volatile organic acids in the oriental tobacco. This paper does offer an alternative approach to determine volatile organic acids in tobacco.
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Affiliation(s)
- Shi-Hao Sun
- ZhengZhou Tobacco Research Institute, China National Tobacco Corporation, ZhengZhou 450001, China
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105
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Gjelstad A, Rasmussen KE, Pedersen-Bjergaard S. Simulation of flux during electro-membrane extraction based on the Nernst–Planck equation. J Chromatogr A 2007; 1174:104-11. [PMID: 17850807 DOI: 10.1016/j.chroma.2007.08.057] [Citation(s) in RCA: 176] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2007] [Revised: 08/23/2007] [Accepted: 08/27/2007] [Indexed: 10/22/2022]
Abstract
The present work has for the first time described and verified a theoretical model of the analytical extraction process electro-membrane extraction (EME), where target analytes are extracted from an aqueous sample, through a thin layer of 2-nitrophenyl octylether immobilized as a supported liquid membrane (SLM) in the pores in the wall of a porous hollow fibre, and into an acceptor solution present inside the lumen of the hollow fibre by the application of an electrical potential difference. The mathematical model was based on the Nernst-Planck equation, and described the flux over the SLM. The model demonstrated that the magnitude of the electrical potential difference, the ion balance of the system, and the absolute temperature influenced the flux of analyte across the SLM. These conclusions were verified by experimental data with five basic drugs. The flux was strongly dependent of the potential difference over the SLM, and increased potential difference resulted in an increase in the flux. The ion balance, defined as the sum of ions in the donor solution divided by the sum of ions in the acceptor solution, was shown to influence the flux, and high ionic concentration in the acceptor solution relative to the sample solution was advantageous for high flux. Different temperatures also led to changes in the flux in the EME system.
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106
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Fattahi N, Samadi S, Assadi Y, Hosseini MRM. Solid-phase extraction combined with dispersive liquid–liquid microextraction-ultra preconcentration of chlorophenols in aqueous samples. J Chromatogr A 2007; 1169:63-9. [PMID: 17900597 DOI: 10.1016/j.chroma.2007.09.002] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 09/03/2007] [Accepted: 09/05/2007] [Indexed: 11/21/2022]
Abstract
The solid-phase extraction (SPE) joined with the dispersive liquid-liquid microextraction (DLLME) has been developed as an ultra preconcentration technique for the determination of chlorophenols in water samples. Chlorophenols (CPs) were employed as model compounds to assess the extraction procedure and were determined by gas chromatography-electron-capture detection (GC-ECD). In solid-phase extraction-dispersive liquid-liquid microextraction (SPE-DLLME), CPs were adsorbed from a large volume of aqueous samples (100 mL) into 100 mg functionalized styrene-divinylbenzene polymer (PPL) sorbent. After the elution of the desired compounds from the sorbent by using acetone, DLLME technique was performed on the obtained solution. Some important extraction parameters, such as sample solution flow rate, breakthrough volume, sample pH, type and volume of the elution solvent as well as the salt addition, were studied and optimized. The new method (SPE-DLLME) provided an ultra enrichment factor (4390-17,870) for 19 CPs. The calibration graphs were linear in the range of 0.001-20 microg L(-1) and the limits of detection (LODs) ranged from 0.0005 to 0.1 microg L(-1). The relative standard deviations (RSDs, for 10.0 microg L(-1) of MCPs, 5.00 microg L(-1) of DCPs, 0.200 microg L(-1) of TCPs, 0.100 microg L(-1) of TeCPs and PCP) with and without the internal standard varied from 1.1 to 6.4% (n=7) and 2.5-9.7% (n=7), respectively. The relative recoveries of the well, tap and river water samples, spiked with different levels of CPs, were 71-110%, 73-115% and 88-121%, respectively.
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Affiliation(s)
- Nazir Fattahi
- Department of Analytical Chemistry, Faculty of Chemistry, Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Tehran, Iran
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107
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Pezo D, Salafranca J, Nerín C. Development of an automatic multiple dynamic hollow fibre liquid-phase microextraction procedure for specific migration analysis of new active food packagings containing essential oils. J Chromatogr A 2007; 1174:85-94. [PMID: 17765253 DOI: 10.1016/j.chroma.2007.08.033] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2007] [Revised: 08/09/2007] [Accepted: 08/13/2007] [Indexed: 11/26/2022]
Abstract
A two-phase based hollow fibre liquid-phase microextraction (HFLPME) with a high automatization degree and able to process up to six samples simultaneously by means of a multiple channel syringe pump has been successfully developed. The experimental set-up allows to carry out dynamic extractions with a considerable reduction of sample handling. The system has been applied for the first time to the determination in aqueous food simulant of migrants from prototypes of active packagings to assess their safety before marketing, showing detection limits in the ng g(-1) range, relative standard deviations below 13% and concentration factors ranging from 83 to 338.
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Affiliation(s)
- Davinson Pezo
- Department of Analytical Chemistry, Aragon Institute of Engineering Research I3A, CPS-University of Zaragoza, Torres Quevedo Building, María de Luna St. 3, E-50018 Zaragoza, Spain
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108
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Fattahi N, Assadi Y, Hosseini MRM, Jahromi EZ. Determination of chlorophenols in water samples using simultaneous dispersive liquid–liquid microextraction and derivatization followed by gas chromatography-electron-capture detection. J Chromatogr A 2007; 1157:23-9. [PMID: 17512936 DOI: 10.1016/j.chroma.2007.04.062] [Citation(s) in RCA: 270] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2007] [Revised: 04/25/2007] [Accepted: 04/26/2007] [Indexed: 10/23/2022]
Abstract
Simultaneous dispersive liquid-liquid microextraction (DLLME) and derivatization combined with gas chromatography-electron-capture detection (GC-ECD) was used to determine chlorophenols (CPs) in water sample. In this derivatization/extraction method, 500 microL acetone (disperser solvent) containing 10.0 microL chlorobenzene (extraction solvent) and 50 microL acetic anhydride (derivatization reagent) was rapidly injected by syringe in 5.00 mL aqueous sample containing CPs (analytes) and K(2)CO(3) (0.5%, w/v). Within a few seconds the analytes derivatized and extracted at the same time. After centrifugation, 0.50 microL of sedimented phase containing enriched analytes was determined by GC-ECD. Some effective parameters on derivatization and extraction, such as extraction and disperser solvent type and their volume, amount of derivatization reagent, derivatization and extraction time, salt addition and amount of K(2)CO(3) were studied and optimized. Under the optimum conditions, enrichment factors and recoveries are in the range of 287-906 and 28.7-90.6%, respectively. The calibration graphs are linear in the range of 0.02-400 microg L(-1) and limit of detections (LODs) are in the range of 0.010-2.0 microg L(-1). The relative standard deviations (RSDs, for 200 microg L(-1) of MCPs, 100 microg L(-1) of DCPs, 4.00 microg L(-1) of TCPs, 2.00 microg L(-1) of TeCPs and PCP in water) with and without using internal standard are in the range of 0.6-4.7% (n=7) and 1.7-7.1% (n=7), respectively. The relative recoveries of well, tap and river water samples which have been spiked with different levels of CPs are 91.6-104.7, 80.8-117.9 and 83.3-101.3%, respectively. The obtained results show that simultaneous DLLME and derivatization combined with GC-ECD is a fast simple method for the determination of CPs in water samples.
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Affiliation(s)
- Nazir Fattahi
- Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Tehran, Iran
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109
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Gjelstad A, Andersen TM, Rasmussen KE, Pedersen-Bjergaard S. Microextraction across supported liquid membranes forced by pH gradients and electrical fields. J Chromatogr A 2007; 1157:38-45. [PMID: 17521660 DOI: 10.1016/j.chroma.2007.05.007] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 04/30/2007] [Accepted: 05/02/2007] [Indexed: 11/24/2022]
Abstract
The present work has for the first time compared extraction of basic analytes across a supported liquid membrane (SLM) based on (1) passive diffusion in a pH gradient sustained over the SLM and (2) electrokinetic migration in an electrical field sustained over the SLM. For the passive diffusion experiments, performed as liquid-phase microextraction (LPME), five basic drugs were extracted under strong agitation from alkaline samples (10mM NaOH), through 2-nitrophenyl octylether immobilized in the pores of a porous hollow fibre of polypropylene (SLM), and into 25 microl of 10mM HCl as the acceptor solution. The experiments based on electrokinetic migration, performed as electro membrane isolation (EMI), were conducted under strong agitation from acidic samples (10mM HCl), through the same SLM as in LPME, and into 25 microl of 10mM HCl as the acceptor solution. Whereas LPME relied on diffusion and to some extent also convection as the principal mechanisms of mass transfer, mass transfer in EMI also included a strong contribution from electrokinetic migration. Thus, extraction kinetics was improved by a factor between 6 and 17 utilizing EMI instead of LPME. This major difference in terms of speed was especially pronounced from small sample volumes (150 microl), and suggest that EMI may be a very interesting future concept for miniaturized sample preparation. In addition to improved extraction kinetics, extraction rates were strongly compound dependent in EMI, opening the possibility to control the extraction selectivity by the extraction time.
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110
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Fiamegos YC, Stalikas CD. In-drop derivatisation liquid-phase microextraction assisted by ion-pairing transfer for the gas chromatographic determination of phenolic endocrine disruptors. Anal Chim Acta 2007; 597:32-40. [PMID: 17658310 DOI: 10.1016/j.aca.2007.06.021] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Revised: 06/07/2007] [Accepted: 06/10/2007] [Indexed: 10/23/2022]
Abstract
A novel in-drop derivatisation liquid-phase microextraction procedure with an ion-pairing agent is developed and optimised for the extraction of endocrine-disrupting chemicals. The ethyl esters of the analytes were rapidly formed in the organic drop and analysed by gas chromatography. The effects of various parameters such as rate and time of agitation, ion-pairing agent and reactant concentration, pH and temperature were studied systematically to optimise the process and bring out the locale of reaction in the organic drop. A study of the mechanistic pathways of the overall procedure is attempted leading to interesting findings and delineating important points of the kinetics and mechanism. A mechanistic model is proposed on the basis of the theory of mass transfer with chemical reaction in two liquid phases. The O-ethoxycarbonyl derivatisation appears to take place in the bulk organic phase. The system provides insight into the first reported analytical case of single-drop extraction-preconcentration-derivatisation assisted by an ion-pairing transfer and has all of the interesting facets of chemical reaction in which the role of mass transfer comes into picture. The analytical features of the method are acceptable and the overall relative standard deviations of the intra-day repeatability (n=5) and inter-day reproducibility were <3.9% and <5.4%, respectively, for gas chromatography-mass spectrometry analyses and <4.3% and <7.1% for gas chromatography-flame ionisation detection analyses. The method was applicable to urine and surface water samples. The LODs ranged between 0.2-1.3 ng mL(-1) and 8.5-26.5 ng mL(-1) for GC/MS and GC/FID analyses, respectively.
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Affiliation(s)
- Yiannis C Fiamegos
- Laboratory of Analytical Chemistry, Chemistry Department, University of Ioannina, 45110 Ioannina, Greece
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111
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Lambropoulou DA, Konstantinou IK, Albanis TA. Recent developments in headspace microextraction techniques for the analysis of environmental contaminants in different matrices. J Chromatogr A 2007; 1152:70-96. [PMID: 17379234 DOI: 10.1016/j.chroma.2007.02.094] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Revised: 02/23/2007] [Accepted: 02/26/2007] [Indexed: 11/24/2022]
Abstract
Headspace microextraction procedures such as solid-phase microextraction (SPME) and single drop microextraction (SDME) or liquid-phase microextraction (LPME) are increasingly used for the extraction of environmental organic pollutants from a variety of aqueous, viscous, semisolid and solid environmental and biological matrices. In this article, recent analytical applications of these methodologies when used as an isolation and trace enrichment step prior to the analysis of organic pollutants (pesticides, polycyclic aromatic hydrocarbons, polychlorinated compounds, organotin compounds, phenolic derivatives, aromatic amines, phthalates, etc.) by gas and liquid chromatography are reviewed. The applicability and inherent limitations of headspace microextraction are also discussed. The future direction of research in this field and general trends toward commercial applications are considered.
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Affiliation(s)
- Dimitra A Lambropoulou
- Laboratory of Environmental Technology, Department of Chemistry, University of Ioannina, Ioannina 45110, Greece.
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112
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Balchen M, Gjelstad A, Rasmussen KE, Pedersen-Bjergaard S. Electrokinetic migration of acidic drugs across a supported liquid membrane. J Chromatogr A 2007; 1152:220-5. [PMID: 17126351 DOI: 10.1016/j.chroma.2006.10.096] [Citation(s) in RCA: 191] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2006] [Revised: 10/25/2006] [Accepted: 10/30/2006] [Indexed: 11/29/2022]
Abstract
Electrokinetic cross membrane extraction of acidic drugs was demonstrated for the first time. The acidic drugs were extracted from an alkaline aqueous donor solution (300 microl), through a thin supported liquid membrane of 1-heptanol sustained in the pores of the wall of a porous hollow fiber, and into an aqueous alkaline acceptor solution (30 microl) present inside the lumen of the hollow fiber by the application of a d.c. electrical potential. The negative electrode was placed in the donor solution, and the positive electrode was placed in the acceptor solution. Optimal extractions were accomplished with 1-heptanol as the supported liquid membrane, with 50 V as the driving force, and with pH 12.0 in both the donor and acceptor solutions, respectively (NaOH). Equilibrium extraction conditions were obtained after 5 min of operation with the whole assembly agitated at 1200 rpm. Eleven different acidic drugs were extracted with recovery values between 8 and 100%, and initial data supported that electrokinetic cross membrane extraction provided repeatable data and linear response between original donor concentration and final acceptor concentration of the acidic model compounds.
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Affiliation(s)
- Marte Balchen
- School of Pharmacy, University of Oslo, Blindern, 0316 Oslo, Norway
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113
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Simões NG, Cardoso VV, Ferreira E, Benoliel MJ, Almeida CMM. Experimental and statistical validation of SPME-GC-MS analysis of phenol and chlorophenols in raw and treated water. CHEMOSPHERE 2007; 68:501-10. [PMID: 17292443 DOI: 10.1016/j.chemosphere.2006.12.057] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Revised: 12/14/2006] [Accepted: 12/18/2006] [Indexed: 05/13/2023]
Abstract
A procedure based on solid-phase microextraction (SPME) and gas chromatography coupled with mass spectrometry (GC-MS) was developed and validated in order to analyse 10 phenols in water samples. The optimised conditions were obtained using polyacrylate fibre (PA), 20ml of sample volume, 10% NaCl, pH 4.0 and direct extraction at 35 degrees C and 1000rpm, for 40min. The linear range and quantification limits for these compounds by SPME-GC-MS were defined. An evaluation of the main uncertainty sources of this method is included, which allows expanded uncertainties in the 9.4-35% range for the majority of the compounds. The main source of uncertainty is associated with matrix effects. The validated method is suitable for monitoring the production and distribution of potable water and was used, in field trials, for the analysis of samples from main intakes of water (surface or underground) and from water supply system of a large area (Lisbon and neighbour municipalities).
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Affiliation(s)
- Natércia Guerra Simões
- Master in Food Toxicology and Quality Control, Faculdade de Farmácia da Universidade de Lisboa (FFUL), Av. das Forças Armadas, 1649-019 Lisboa, Portugal
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114
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Bai-Juan Y, Feng-Hua J, Xiao-Qin X, Jun-Hui C, Lee FS. Determination of Alkylphenols in Water by Solid-Phase Extraction with On-column Derivatization Coupled with Gas Chromatography-Mass Spectrometry. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2007. [DOI: 10.1016/s1872-2040(07)60050-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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115
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Lee HSN, Sng MT, Basheer C, Lee HK. Determination of degradation products of chemical warfare agents in water using hollow fibre-protected liquid-phase microextraction with in-situ derivatisation followed by gas chromatography–mass spectrometry. J Chromatogr A 2007; 1148:8-15. [PMID: 17376465 DOI: 10.1016/j.chroma.2007.02.104] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 02/22/2007] [Accepted: 02/23/2007] [Indexed: 10/23/2022]
Abstract
Hollow fibre-protected liquid-phase microextraction (HF-LPME) together with gas chromatography/mass spectrometry was investigated for the analysis of degradation products of chemical warfare agents in water samples. The degradation products studied were those of nerve and blister agents, and a psychotomimetic agent. Extractions were successfully performed coupled with in-situ derivatisation using a mixture of solvent and derivatising agent. The protection of the moisture-sensitive derivatising agent was afforded by the hollow fibre. Parameters such as extraction solvent, pH, salt concentration, stirring speed and extraction time were optimised using spiked deionised water samples. The linear range established was between 0.005 and 5 microg ml(-1) depending on analyte, with squared regression coefficients ranging from 0.9929 to 1.0000. Relative standard deviations ranged from 9% to 22%. As compared to those of solid-phase microextraction, the limits of detection (0.01-0.54 microg l(-1)) of the newly-developed approach were significantly improved.
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Affiliation(s)
- Hoi Sim Nancy Lee
- DSO National Laboratories, 20 Science Park Drive, Singapore 118230, Singapore
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116
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Fan J, Guo HQ, Feng SL. Spectrofluorimetric Determination of Pentachlorophenol Based on Its Inhibitory Effect on The Redox Reaction Between Hydroxyl Radicals and Fluorescent Dye Rhodamine B. J Fluoresc 2007; 17:257-64. [PMID: 17473907 DOI: 10.1007/s10895-007-0167-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Accepted: 02/01/2007] [Indexed: 12/01/2022]
Abstract
Hydroxyl radicals that is generated by Fenton reagent reacts with rhodamine B, which makes the fluorescence quenching of rhodamine B. However, there is an inhibitory effect of pentachlorophenol on the reaction. Based on this observation, an inhibitory fluorimetric method is reported for the determination of trace pentachlorophenol. The fluorescent inhibition of rhodamine B is measured by fix-time method. On the optimum conditions of experimentation, the detection limit for pentachlorophenol is 3.0 ng/ml and the linear range of the determination is 4.0-240 ng/ml. Combined with the samples treating with ion exchange resins and XDA-1 absorption resin, the method has been used for the determination of pentachlorophenol in synthetic samples and natural water samples with satisfactory results. We have also discussed the possible mechanism of the reaction.
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Affiliation(s)
- Jing Fan
- School of Chemistry and Environmental Science, Henan Key Laboratory for Environmental, Pollution Control, Henan Normal University, Xinxiang, Henan 453007, P.R. China.
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117
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Zhao RS, Yuan JP, Li HF, Wang X, Jiang T, Lin JM. Nonequilibrium hollow-fiber liquid-phase microextraction with in situ derivatization for the measurement of triclosan in aqueous samples by gas chromatography-mass spectrometry. Anal Bioanal Chem 2007; 387:2911-5. [PMID: 17377785 DOI: 10.1007/s00216-007-1151-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 01/15/2007] [Accepted: 01/24/2007] [Indexed: 10/23/2022]
Abstract
Hollow-fiber liquid-phase microextraction (HF-LPME), a relatively new sample preparation technique, has attracted much interest in the field of environmental analysis. In the current study, a novel method based on hollow-fiber liquid-phase microextraction with in situ derivatization and gas chromatography-mass spectrometry for the measurement of triclosan in aqueous samples is described. Hollow-fiber liquid-phase microextraction conditions such as the type of extraction solvent, the stirring rate, the volume of derivatizing reagent, and the extraction time were investigated. When the conditions had been optimized, the linear range was found to be 0.05-100 microg l(-1) for triclosan, and the limit of detection to be 0.02 microg l(-1). Tap water and surface water samples collected from our laboratory and Wohushan reservoir, respectively, were successfully analyzed using the proposed method. The recoveries from the spiked water samples were 83.6 and 114.1%, respectively; and the relative standard deviation (RSD) at the 1.0 microg l(-1) level was 6.9%.
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Affiliation(s)
- Ru-Song Zhao
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China.
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118
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Gatidou G, Thomaidis NS, Stasinakis AS, Lekkas TD. Simultaneous determination of the endocrine disrupting compounds nonylphenol, nonylphenol ethoxylates, triclosan and bisphenol A in wastewater and sewage sludge by gas chromatography–mass spectrometry. J Chromatogr A 2007; 1138:32-41. [PMID: 17070818 DOI: 10.1016/j.chroma.2006.10.037] [Citation(s) in RCA: 265] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2006] [Revised: 10/17/2006] [Accepted: 10/18/2006] [Indexed: 11/26/2022]
Abstract
An integrated analytical method for the simultaneous determination of 4-n-nonylphenol (4-n-NP), nonylphenol monoethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO), bisphenol A (BPA) and triclosan (TCS) in wastewater (dissolved and particulate phase) and sewage sludge was developed based on gas chromatography-mass spectrometry. Chromatographic analysis was achieved after derivatization with bis(trimethylsilyl)trifluoroacetamide (BSTFA). Extraction from water samples was performed by solid-phase extraction (SPE). The optimization of SPE procedure included the type of sorbent and the type of the organic solvent used for the elution. Referred to solid samples, the target compounds were extracted by sonication. In this case the optimization of the extraction procedure included the variation of the amount of the extracted biomass, the duration and the temperature of sonication and the type of the extraction organic solvent. The developed extraction procedures resulted in good repeatability and reproducibility with relative standard deviations (RSDs) less than 13% for all the tested compounds for both types of samples. Satisfactory recoveries were obtained (>60%) for all the compounds in both liquid and solid samples, except for 4-n-NP, which gave recoveries up to 35% in wastewater samples and up to 63% in sludge samples. The limits of detection (LODs) of the target compounds varied from 0.03 (4-n-NP) to 0.41 microg l(-1) (NP2EO) and from 0.04 (4-n-NP) to 0.96 microg kg(-1) (NP2EO) for liquid and solid samples, respectively. The developed methods were successfully applied to the analysis of the target compounds in real samples.
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Affiliation(s)
- Georgia Gatidou
- Laboratory of Analytical Chemistry, Department of Chemistry, University of Athens, Panepistimioupolis Zografou, 15771 Athens, Greece
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119
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Guo H, Fan J, Guo Y. A fluorimetric method for the determination of trace pentachlorophenol, based on its inhibitory effect on the redox reaction between the improved Fenton reagent and rhodamine B. LUMINESCENCE 2007; 22:407-14. [PMID: 17471461 DOI: 10.1002/bio.977] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A sensitive fluorimetric method is presented and discussed for the determination of pentachlorophenol in aqueous solutions. This method is based on the inhibitory effect of pentachlorophenol on the reaction of conventional Fenton [Fe(III) + H(2)O(2)] reagent with rhodamine B in the medium of perchloric acid, which results in the fluorescence quenching of rhodamine B. It was further found that the sensitivity for the determination was improved significantly when the molecular ligand EDTA was added. This improved system was therefore presented for the determination of pentachlorophenol. The characteristics of the excitation and emission spectra, optimization of the experimental conditions, the stability of the system and the influence of foreign matter have all been investigated. Under optimal conditions, the linear range for the determination of pentachlorophenol is 12-480 ng/mL with a 3sigma limit of detection of 0.96 ng/mL. Compared with the conventional Fenton system, the improved system shows obvious advantages in both sensitivity and selectivity. By combination with the pretreatment of samples using ion exchange resins and XDA-1 absorption resin, the improved Fenton method was used for the first time for the determination of pentachlorophenol in synthetic samples and natural water samples, and satisfactory results, in agreement with those of the HPLC method, were achieved. The possible mechanism of the reactions has also been discussed.
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Affiliation(s)
- Huiqin Guo
- School of Chemistry and Environmental Science, Henan Key Laboratory for Environmental Pollution Control, Henan Normal University, Xinxiang, Henan 453007, People's Republic of China
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120
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Chapter 2.5 Analysis of acidic drugs by gas chromatography. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0166-526x(07)50006-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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121
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Zhao RS, Cheng CG, Yuan JP, Jiang T, Wang X, Lin JM. Sensitive measurement of ultratrace phenols in natural water by purge-and-trap with in situ acetylation coupled with gas chromatography-mass spectrometry. Anal Bioanal Chem 2006; 387:687-94. [PMID: 17139487 DOI: 10.1007/s00216-006-0890-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 09/24/2006] [Accepted: 10/02/2006] [Indexed: 10/23/2022]
Abstract
A novel purge-and-trap method coupled with gas chromatography-mass spectrometry (GC-MS) is developed for the analysis of trace and ultratrace phenols based on their derivatization with acetic anhydride. Parameters affecting the extraction efficiency, such as purge temperature, concentration of sodium chloride, purge time, and volume of derivatization reagent, were investigated. The optimized conditions were addition of 150 microL acetic anhydride, purge time of 25 min at the purge temperature of 60 degrees C with 30% NaCl. The linear range was 0.2-100 microg L(-1) for phenols. The limits of detection (LODs) ranged from 0.08 to 0.15 microg L(-1) and the relative standard deviations (RSDs) for most of the phenols at the 10 microg L(-1) level were below 10%. Natural water samples collected from a pool were successfully analyzed using the proposed method. The recovery of spiked water samples was 72.9-84.2%.
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Affiliation(s)
- Ru-Song Zhao
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, People's Republic of China.
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122
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Campillo N, Peñalver R, Hernández-Córdoba M. Evaluation of solid-phase microextraction conditions for the determination of chlorophenols in honey samples using gas chromatography. J Chromatogr A 2006; 1125:31-7. [PMID: 16769077 DOI: 10.1016/j.chroma.2006.05.051] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Revised: 05/10/2006] [Accepted: 05/15/2006] [Indexed: 10/24/2022]
Abstract
A rapid and solvent-free method for the determination of nine chlorophenol (CP) compounds in honey samples using headspace solid-phase microextraction (HS-SPME) and gas chromatography with atomic emission detection (GC-AED) is developed. The different factors affecting the efficiency of the extraction and derivatization steps were carefully optimized. The polydimethylsiloxane-divinylbenzene (PDMS/DVB) fiber was the most suitable for preconcentrating the analytes from the headspace of an aqueous solution containing the dissolved honey samples where the chlorophenols had been submitted to acetylation. When the matrix effect was evaluated for different samples, it was concluded that standard addition calibration was required for quantification purposes. Detection limits roughly ranged from 0.1 to 2.4 ng g(-1), depending on the compound and the honey sample analyzed, with a fiber time exposure of only 15 min at 75 degrees C. The optimized method was successfully applied to different samples, some of the studied chlorophenols being detected in some of the analyzed honeys at concentration levels 0.6-9.4 ng g(-1).
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Affiliation(s)
- Natalia Campillo
- Department of Analytical Chemistry, Faculty of Chemistry, University of Murcia, E-30071 Murcia, Spain
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123
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Basheer C, Alnedhary AA, Rao BSM, Valliyaveettil S, Lee HK. Development and Application of Porous Membrane-Protected Carbon Nanotube Micro-Solid-Phase Extraction Combined with Gas Chromatography/Mass Spectrometry. Anal Chem 2006; 78:2853-8. [PMID: 16615802 DOI: 10.1021/ac060240i] [Citation(s) in RCA: 290] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A novel, multiwalled carbon nanotube (MWCNT)-supported micro-solid-phase extraction (mu-SPE) procedure has been developed. A 6-mg sample of MWCNTs was packed inside a (2 cm x 1.5 cm) sheet of porous polypropylene membrane whose edges were heat-sealed to secure the contents. The mu-SPE device, which was wetted with dichloromethane, was then placed in a stirred sewage sludge sample solution to extract organophosporous pesticides, used here as model compounds. Tumbling of the extraction device within the sample solution facilitated extraction, and the porous membrane acted as a filter to exclude the extraction of extraneous materials. After extraction, analytes were desorbed in hexane and analyzed using gas chromatography/mass spectrometry. Since the porous membrane afforded protection of the MWCNTs, no further cleanup of the extract was required. The pi-pi electrostatic interaction with the analytes and the large surface area of MWCNTs facilitated the adsorption of analytes, with good selectivity and reproducibility. Under the optimized extraction conditions, the method showed good linearity in the range of 0.1-50 mug/L, repeatability of the extractions (RSD 2-8%, n = 4), and low limits of detection (1-7 pg/g). No analyte carryover effect was observed, and each mu-SPE device could be used for up to 30 extractions. Comparison was made with hollow fiber protected solid-phase microextraction and headspace solid-phase microextraction; mu-SPE was demonstrated to be a fast, accurate, and cost-effective pretreatment method for sewage sludge samples.
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Affiliation(s)
- Chanbasha Basheer
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore
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124
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Quintana JB, Rodríguez I. Strategies for the microextraction of polar organic contaminants in water samples. Anal Bioanal Chem 2006; 384:1447-61. [PMID: 16496135 DOI: 10.1007/s00216-005-0242-z] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2005] [Revised: 11/14/2005] [Accepted: 11/18/2005] [Indexed: 10/25/2022]
Abstract
In this paper the most recent developments in the microextraction of polar analytes from aqueous environmental samples are critically reviewed. The particularities of different microextraction approaches, mainly solid-phase microextraction (SPME), stir-bar-sorptive extraction (SBSE), and liquid-phase microextraction (LPME), and their suitability for use in combination with chromatographic or electrically driven separation techniques for determination of polar species are discussed. The compatibility of microextraction techniques, especially SPME, with different derivatisation strategies enabling GC determination of polar analytes and improving their extractability is revised. In addition to the use of derivatisation reactions, the possibility of enhancing the yield of solid-phase microextraction methods for polar analytes by using new coatings and/or larger amounts of sorbent is also considered. Finally, attention is also focussed on describing the versatility of LPME in its different possible formats and its ability to improve selectivity in the extraction of polar analytes with acid-base properties by using separation membranes and buffer solutions, instead of organic solvents, as the acceptor solution.
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Affiliation(s)
- José Benito Quintana
- Department of Water Quality Control, Technical University of Berlin, Sekr KF 4, Strasse des 17 Juni 135, 10623, Berlin, Germany.
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125
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Kawaguchi M, Ito R, Endo N, Okanouchi N, Sakui N, Saito K, Nakazawa H. Liquid phase microextraction with in situ derivatization for measurement of bisphenol A in river water sample by gas chromatography-mass spectrometry. J Chromatogr A 2006; 1110:1-5. [PMID: 16472528 DOI: 10.1016/j.chroma.2006.01.061] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2005] [Revised: 01/10/2006] [Accepted: 01/12/2006] [Indexed: 10/25/2022]
Abstract
A new method that involves liquid phase microextraction (LPME) with in situ derivatization and gas chromatography-mass spectrometry (GC-MS) is described for the determination of trace amounts of bisphenol A (BPA) in river water samples. The LPME conditions, such as the type of extraction solvent and the extraction time, are investigated. Then, the extract is directly injected into GC-MS. The detection limit and the quantification limit of BPA in river water sample are 2 and 10pgml(-1) (ppt), respectively. The calibration curve for BPA is linear with a correlation coefficient of >0.999 in the range of 10-10,000pgml(-1). The average recoveries of BPA in river water samples spiked with 100 and 1000pgml(-1) BPA are 104.1 (RSD: 8.9%) and 98.3 (RSD: 3.2%), respectively, with correction using the added surrogate standard, bisphenol A-(13)C(12). This simple, accurate, sensitive and selective analytical method may be applicable to the determination of trace amounts of BPA in liquid samples.
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Affiliation(s)
- Migaku Kawaguchi
- Department of Analytical Chemistry, Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
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126
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Paik MJ, Choi Y, Kim KR. Simultaneous profiling analysis of alkylphenols and amines by gas chromatography and gas chromatography–mass spectrometry. Anal Chim Acta 2006. [DOI: 10.1016/j.aca.2005.12.047] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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127
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Chia KJ, Huang SD. Simultaneous derivatization and extraction of primary amines in river water with dynamic hollow fiber liquid-phase microextraction followed by gas chromatography–mass spectrometric detection. J Chromatogr A 2006; 1103:158-61. [PMID: 16343509 DOI: 10.1016/j.chroma.2005.11.072] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2005] [Revised: 11/18/2005] [Accepted: 11/21/2005] [Indexed: 12/01/2022]
Abstract
A one-step derivatization and extraction technique for the determination of primary amines in river water by liquid-phase microextraction (LPME) is presented. In this method the primary amines are derivatized with pentafluorobenzaldehyde (PFBAY) in aqueous solution and extracted by dynamic hollow fiber-protected-LPME (HF-LPME) simultaneously. The effects of solvent selection, sample agitation, extraction time, extraction temperature and salt concentration on the extraction performance are investigated. High enrichments (172-244-fold) and good repeatabilities (RSD less than 7.2%) were obtained. Linearity in this developed method was ranging from 1 to 500 ng/ml, and the correlation coefficients (R2) were between 0.992 and 0.998. Comparisons of sensitivity and precision between dynamic HF-LPME and single-drop liquid-phase microextraction (SDME) were also made.
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Affiliation(s)
- Kan-Jung Chia
- Department of Chemistry, National Tsing Hua University, Hsinchu 30043, Taiwan
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128
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Dietz C, Sanz J, Cámara C. Recent developments in solid-phase microextraction coatings and related techniques. J Chromatogr A 2006; 1103:183-92. [PMID: 16337213 DOI: 10.1016/j.chroma.2005.11.041] [Citation(s) in RCA: 223] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2005] [Revised: 11/08/2005] [Accepted: 11/14/2005] [Indexed: 11/28/2022]
Abstract
During the last decade, solid-phase microextraction (SPME) has gained widespread acceptance for analyte matrix separation and preconcentration. Relatively few data are currently available dealing with in-house production of fibres with tailor-made properties to be used for SPME, though recently the number of publications evaluating new coatings has been considerably growing. This review, centred on publications that appeared during the last five years, is resuming different approaches which can be used for fibre production and further summarises alternative techniques closely related to SPME, such as in-tube extraction or single-drop microextraction (SDME). The aim is to give the reader a concise overview of recent developments in new coating procedures and materials, including the respective applications.
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Affiliation(s)
- Christian Dietz
- Department of Analytical Chemistry, Faculty of Chemistry, University Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain
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129
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Tsai WT. Human health risk on environmental exposure to Bisphenol-A: a review. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, ENVIRONMENTAL CARCINOGENESIS & ECOTOXICOLOGY REVIEWS 2006; 24:225-55. [PMID: 17114111 DOI: 10.1080/10590500600936482] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Bisphenol-A (BPA), identified as an environmental hormone (i.e., endocrine disruptor), is an industrially important chemical that is being used as a primary raw material for the production of engineering plastics (e.g., polycarbonate/epoxy resins), food cans (i.e., lacquer coatings), and dental composites/sealants. From the ecotoxicology, human health and regulatory points of view, it is urgent to restrict the emissions and releases of the estrogenic chemical from the industrial processes and commercial products. This article reviews BPA in the current literature in terms of physiochemical properties, industrial/commercial uses, environmental distributions in the atmospheric/aquatic/terrestrial phases, possible human toxicity, and its exposure standards and limits. Emphasis is put on the most significant distribution in the aquatic environment, and occupational and non-occupational human exposures. Overall, it is strongly convinced that BPA is not a carcinogenic risk to humans, and is also rapidly glucuronidated and excreted through the route of urine.
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Affiliation(s)
- Wen-Tien Tsai
- Graduate Institute of Bioresources, National Pingtung University of Science and Technology, Pingtung, Taiwan.
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130
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Basheer C, Parthiban A, Jayaraman A, Lee HK, Valiyaveettil S. Determination of alkylphenols and bisphenol-A. J Chromatogr A 2005; 1087:274-82. [PMID: 16130724 DOI: 10.1016/j.chroma.2005.03.014] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A functional polymer (hydroxylated polymethacrylate) coated on porous polysulfone hollow fiber membrane (PS-HFM) was used as an adsorbent for the extraction of alkylphenols and bisphenol-A from seawater samples. Analyses of the extracts were performed using gas chromatography-mass spectrometry (GC-MS) after injection-port derivatization using bis(trimethylsilyl)trifluoroacetamide (BSTFA). We term the procedure as polymer-coated hollow fiber microextraction (PC-HFME). Owing to high porosity PS-HFM coated with hydroxylated polymer showed high extraction efficiency. Compared with solid-phase microextraction (SPME), PC-HFME showed good selectivity and sensitivity. Detection limits of alkylphenols and bisphenol-A ranged between 0.07 and 2.34 ng l(-1). The linearity range was from 0.01 to 15 microg l(-1) and the correlation coefficient (r) up to 0.997. The sensitivity and selectivity of the coated HFM could be potentially tuned by changing the characteristics of the coated hydroxylated polymer. The PC-HFME procedure was applied to the detection of alkylphenols and bisphenol-A in the coastal waters of Singapore.
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Affiliation(s)
- Chanbasha Basheer
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
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131
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Basheer C, Jegadesan S, Valiyaveettil S, Lee HK. Sol–gel-coated oligomers as novel stationary phases for solid-phase microextraction. J Chromatogr A 2005; 1087:252-8. [PMID: 16130721 DOI: 10.1016/j.chroma.2005.02.024] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Amphiphilic and hydrophilic oligomers were synthesized and coated on fused silica capillaries using a sol-gel technique. Sol-gel-coated capillaries were evaluated for the solid-phase microextraction and preconcentration of a wide variety of non-polar and polar analytes. Both types of coatings were stable under high temperature (up to 280 degrees C). The extraction efficiency of the sol-gel coatings was evaluated for the extraction of both non-polar and polar analytes, including organochlorine pesticides, triazine herbicides, estrogens and alkylphenols (APs) and bisphenol-A (BPA). Compared with commercially available solid-phase microextraction (SPME) adsorbents such as poly(dimethylsiloxane)divenylbenzene and polyacrylate, the new materials showed comparable selectivity and sensitivity towards both non-polar and polar analytes. The new coatings gave good linearity and detection limits. For example with triazines, a detection limit of <0.005 microl l(-1), precision from 5.0 to 11.0% (n = 6) and linearity of the calibration plots (0.5 to 50 microl l(-1)) were obtained. The sol-gel coated SPME capillaries were used for the determination of triazine herbicides in reservoir water samples collected in Singapore.
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Affiliation(s)
- Chanbasha Basheer
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
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