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1. Sol–gel based metal-organic framework zeolite imidazolate framework-8 fibers for solid-phase microextraction of nitro polycyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons in water samples

Author:
Kong, Jijie; Zhu, Fengxi; Huang, Wen; He, Huan; Hu, Jiapeng; Sun, Cheng; Xian, Qiming; Yang, Shaogui
Source:
Journal of chromatography 2019 v.1603 pp. 92-101
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; coatings; coordination compounds; desorption; detection limit; environmental assessment; gas chromatography-mass spectrometry; hydrophobicity; mixing; pH; polycyclic aromatic hydrocarbons; solid phase microextraction; stainless steel; standard deviation; tandem mass spectrometry; temperature; zeolites;     Show all 17 Subjects
Abstract:
... In this study, three kinds of Zeolite imidazolate framework-8 (ZIF-8), synthesized by solvothermal, stirring and ball-milling method, were fabricated on the stainless steel wire via sol-gel technique. These fibers were used as solid phase microextraction (SPME) coating materials and applied for analyzing 16 polycyclic aromatic hydrocarbons (PAHs) and 11 nitro polycyclic aromatic hydrocarbons (NPAH ...
DOI:
10.1016/j.chroma.2019.06.063

2. Expanding the application of stir bar sorptive-dispersive microextraction approach to solid matrices: Determination of ultraviolet filters in coastal sand samples

Author:
Benedé, Juan L.; Chisvert, Alberto; Moyano, Carla; Giokas, Dimosthenis L.; Salvador, Amparo
Source:
Journal of chromatography 2018 v.1564 pp. 25-33
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; UV filters; coatings; desorption; detection limit; ethanol; gas chromatography-mass spectrometry; hydrophobicity; magnetism; microextraction; mixing; nanoparticles; pH; recreation; sand; sorbents; statistical analysis;     Show all 17 Subjects
Abstract:
... This work describes a new method for the determination of organic compounds in solid samples based on the equilibrium desorption of the analytes in an aqueous phase followed by stir bar sorptive-dispersive microextraction (SBSDME). Sand samples, contaminated with UV filters due to bathing and recreational activities, were dispersed in an aqueous medium by using a coated stir bar with CoFe2O4@oleic ...
DOI:
10.1016/j.chroma.2018.06.003

3. Magnetic carbon nanotube composite for the preconcentration of parabens from water and urine samples using dispersive solid phase extraction

Author:
Pastor-Belda, Marta; Marín-Soler, Lidia; Campillo, Natalia; Viñas, Pilar; Hernández-Córdoba, Manuel
Source:
Journal of chromatography 2018 v.1564 pp. 102-109
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; acetylation; adsorption; carbon nanotubes; desorption; detection limit; gas chromatography-mass spectrometry; magnetic materials; magnetism; solid phase extraction; solvents; urine; wastewater treatment;     Show all 13 Subjects
Abstract:
... This study describes the use of a magnetic multi-walled carbon nanotube composite for the preconcentration of nine parabens (methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, phenyl and benzylparaben) from water and urine samples after in situ acetylation. The enriched extracts were obtained by dispersive magnetic solid phase extraction (DMSPE) and analysed by gas chromatography with mass ...
DOI:
10.1016/j.chroma.2018.06.025

4. Purification and enrichment of polycyclic aromatic hydrocarbons in environmental water samples by column clean-up coupled with continuous flow single drop microextraction A

Author:
Li, Yue; Zhang, Lening; Wu, Lijie; Sun, Shuang; Shan, Hongyan; Wang, Ziming
Source:
Journal of chromatography 2018
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; detection limit; gas chromatography-mass spectrometry; microextraction; pH; packaging materials; polycyclic aromatic hydrocarbons; solvents; statistical analysis; temperature;     Show all 10 Subjects
Abstract:
... A novel method for the determination of sixteen polycyclic aromatic hydrocarbons (PAHs) in environmental water samples was developed using column clean-up (CCU) coupled with continuous flow single drop microextraction (CF-SDME) prior to the determination by gas chromatography-mass spectrometry (GC–MS). In this method, purification, extraction and enrichment were carried out in a single step, which ...
DOI:
10.1016/j.chroma.2018.07.013

5. New nanostructure of polydimethylsiloxane coating as a solid-phase microextraction fiber: Application to analysis of BTEX in aquatic environmental samples B Analytical technologies in the biomedical and life sciences

Author:
Zali, Sara; Jalali, Fahimeh; Es-haghi, Ali; Shamsipur, Mojtaba
Source:
Journal of chromatography 2016 v.1033-1034 pp. 287-295
ISSN:
1570-0232
Subject:
ionic strength,   etc   ; BTEX (benzene, toluene, ethylbenzene, xylene); agitation; benzene; coatings; desorption; ethylbenzene; gas chromatography-mass spectrometry; headspace analysis; nanoparticles; scanning electron microscopy; solid phase microextraction; stainless steel; temperature; thermal stability; toluene; xylene;     Show all 17 Subjects
Abstract:
... Electrospinning technique was used to convert polydimethyl siloxane (PDMS) sol-gel solution to a new nanostructure on a stainless steel wire. The surface morphology of the fiber was observed by scanning electron microscopy (SEM). It showed a diameter range of 30⿿60nm for PDMS nanoparticles with a homogeneous and porous surface structure. The applicability of this coating was assessed for the heads ...
DOI:
10.1016/j.jchromb.2016.08.045

6. Polydopamine-reinforced magnetization of zeolitic imidazolate framework ZIF-7 for magnetic solid-phase extraction of polycyclic aromatic hydrocarbons from the air-water environment

Author:
Zhang, Suling; Yao, Weixuan; Ying, Jianbo; Zhao, Hongting
Source:
Journal of chromatography 2016 v.1452 pp. 18-26
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; adsorption; air; coordination polymers; desorption; gas chromatography-mass spectrometry; iron oxides; ligands; magnetism; mixing; moieties; nanoparticles; pH; particulates; polycyclic aromatic hydrocarbons; porosity; rain; solid phase extraction; solvents; statistical analysis; surface area; tandem mass spectrometry; zeolites; zinc;     Show all 24 Subjects
Abstract:
... Zeolitic imidazolate frameworks (ZIFs) consist of metal nodes connected to imidazolate linkers, having both the properties of metal-organic frameworks (MOFs) and inorganic zeolites, such as controllable pore sizes, high porosity and surface areas, as well as exceptional thermal and chemical stability, thereby making them a class of attractive materials for diverse analytical applications. In this ...
DOI:
10.1016/j.chroma.2016.05.039

7. In-syringe magnetic stirring-assisted dispersive liquid–liquid microextraction and silylation prior gas chromatography–mass spectrometry for ultraviolet filters determination in environmental water samples

Author:
Clavijo, Sabrina; Avivar, Jessica; Suárez, Ruth; Cerdà, Víctor
Source:
Journal of chromatography 2016 v.1443 pp. 26-34
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; UV filters; acetone; air flow; cosmetics; derivatization; experimental design; gas chromatography-mass spectrometry; liquid-phase microextraction; magnetism; mixing; pH; seawater; silylation; solvents; stainless steel; statistical analysis; trichloroethylene;     Show all 18 Subjects
Abstract:
... A novel online approach involving in-syringe magnetic stirring assisted dispersive liquid–liquid microextraction and derivatization coupled to gas chromatography–mass spectrometry has been developed for the determination of seven UV filters extensively used in cosmetic products in environmental water samples. The effect of parameters such as the type and volume of extraction solvent, dispersive so ...
DOI:
10.1016/j.chroma.2016.03.036

8. Core–shell electrospun polybutylene terephthalate/polypyrrole hollow nanofibers for micro-solid phase extraction

Author:
Bagheri, Habib; Rezvani, Omid; Banihashemi, Solmaz
Source:
Journal of chromatography 2016 v.1434 pp. 19-28
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; desorption; detection limit; gas chromatography-mass spectrometry; moieties; nanofibers; pH; pyrroles; regression analysis; scanning electron microscopy; solvents; sorbents; temperature; triazine herbicides; wheat;     Show all 15 Subjects
Abstract:
... In the present work, a new micro-solid phase extraction (μ-SPE) sorbent as an extracting medium based on core–shell nanofibers was synthesized by electrospinning. The core–shell nanofibers of polyvinylpyrrolidone-Polybutylene terephthalate/polypyrrole (PVP-PBT/PPy) were electrospun and subsequently, modified hollow nanofibers were prepared by removing the central PVP moiety. Moreover, conventional ...
DOI:
10.1016/j.chroma.2015.12.082

9. A metal organic framework-polyaniline nanocomposite as a fiber coating for solid phase microextraction A

Author:
Bagheri, Habib; Javanmardi, Hasan; Abbasi, Alireza; Banihashemi, Solmaz
Source:
Journal of chromatography 2016 v.1431 pp. 27-35
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; aniline; coatings; desorption; electrolytes; gas chromatography-mass spectrometry; headspace analysis; nanocomposites; scanning electron microscopy; solid phase microextraction; stainless steel; statistical analysis; temperature;     Show all 13 Subjects
Abstract:
... A metal organic framework-polyaniline (MOF/PANI) nanocomposite was electrodeposited on a stainless steel wire and used as a solid phase microextraction (SPME) fiber coating. The electropolymerization process was carried out under a constant deposition potential and applied to the corresponding aqueous electrolyte containing aniline and MOF particles. The employment of MOFs with their large and sma ...
DOI:
10.1016/j.chroma.2015.12.077

10. Polydopamine decorated 3D nickel foam for extraction of sixteen polycyclic aromatic hydrocarbons A

Author:
Cai, Ying; Yan, Zhihong; Yang, Ming; Huang, Xiaoying; Min, Weiping; Wang, Lijia; Cai, Qingyun
Source:
Journal of chromatography 2016
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; X-ray photoelectron spectroscopy; adsorption; desorption; detection limit; energy; energy-dispersive X-ray analysis; foams; gas chromatography-mass spectrometry; nickel; pH; polycyclic aromatic hydrocarbons; river water; scanning electron microscopy; solid phase extraction; solvents; statistical analysis; wastewater;     Show all 18 Subjects
Abstract:
... In this work, polydopamine coated 3D nickel foam (NF-PDA) was prepared and applied as sorbent for the solid phase extraction (SPE) of 16 polycyclic aromatic hydrocarbons (PAHs) from water samples. NF-PDA were synthesized by situ oxidative self-polymerization procedure and characterized by using the techniques of scanning electron microscopy (SEM), energy dispersive spectrum analysis (EDS) and X-ra ...
DOI:
10.1016/j.chroma.2016.11.030

11. Graphene oxide-based dispersive solid-phase extraction combined with in situ derivatization and gas chromatography–mass spectrometry for the determination of acidic pharmaceuticals in water A

Author:
Naing, Nyi Nyi; Li, Sam Fong Yau; Lee, Hian Kee
Source:
Journal of chromatography 2015 v.1426 pp. 69-76
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; derivatization; desorption; detection limit; diclofenac; gas chromatography-mass spectrometry; gemfibrozil; graphene; graphene oxide; ibuprofen; ketoprofen; models; pH; quaternary ammonium compounds; solid phase extraction; solvents; sorbents; statistical analysis;     Show all 18 Subjects
Abstract:
... A fast and low-cost sample preparation method of graphene based dispersive solid-phase extraction combined with gas chromatography–mass spectrometric (GC–MS) analysis, was developed. The procedure involves an initial extraction with water-immiscible organic solvent, followed by a rapid clean-up using amine functionalized reduced graphene oxide as sorbent. Simple and fast one-step in situ derivatiz ...
DOI:
10.1016/j.chroma.2015.11.070

12. Analysis of volatile phenols in alcoholic beverage by ethylene glycol-polydimethylsiloxane based stir bar sorptive extraction and gas chromatography–mass spectrometry A

Author:
Zhou, Qin; Qian, Yanping; Qian, Michael C.
Source:
Journal of chromatography 2015 v.1390 pp. 22-27
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; beers; composite polymers; correlation; ethanol; ethylene; ethylene glycol; gas chromatography-mass spectrometry; pH; phenols; phosphates; wines;     Show all 12 Subjects
Abstract:
... An ethylene glycol (EG)/polydimethylsiloxane (PDMS) copolymer based stir bar sorptive extraction (SBSE)-GC–MS method was developed for the analysis of volatile phenols (4-ethylphenol, 4-vinylphenol, 4-ethylguaiacol, and 4-vinylguaiacol) in alcoholic beverages. The beverage samples were diluted with phosphate buffer (1M, pH 7) and extracted with an EG/PDMS stir bar. Volatile phenols were thermally ...
DOI:
10.1016/j.chroma.2015.02.064

13. Nanoscale-supported heteropoly acid as a new fiber coating for solid-phase microextraction coupled with gas chromatography–mass spectrometry A

Author:
Abolghasemi, Mir Mahdi; Hassani, Sona; Rafiee, Ezzat; Yousefi, Vahid
Source:
Journal of chromatography 2015 v.1381 pp. 48-53
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; Fourier transform infrared spectroscopy; coatings; desorption; equipment; ferric oxide; gas chromatography-mass spectrometry; maghemite; mixing; nanocomposites; nanoparticles; pH; phenolic compounds; scanning electron microscopy; solid phase microextraction; stainless steel; statistical analysis; surface area; temperature; thermal stability;     Show all 20 Subjects
Abstract:
... In the present study, 12-tungstophosphoric (PW) acid as heteropoly acid, supported on silica-coated γ-Fe2O3 nanoparticles (NPs), was used as a new fiber coating for solid-phase microextraction (SPME). The γ-Fe2O3@SiO2-PW nanocomposite with high surface area was synthesized and characterized by SEM and FT-IR. The prepared nanocomposite was immobilized on a stainless steel wire for fabrication of th ...
DOI:
10.1016/j.chroma.2014.12.080

14. Roles of inorganic oxide nanoparticles on extraction efficiency of electrospun polyethylene terephthalate nanocomposite as an unbreakable fiber coating A

Author:
Bagheri, Habib; Roostaie, Ali
Source:
Journal of chromatography 2015 v.1375 pp. 8-16
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; BTEX (benzene, toluene, ethylbenzene, xylene); benzene; coatings; desorption; detection limit; ethylbenzene; gas chromatography-mass spectrometry; headspace analysis; iron oxides; models; nanocomposites; nanofibers; nanoparticles; nickel oxide; polyethylene; polyethylene terephthalates; scanning electron microscopy; silica; solid phase microextraction; stainless steel; statistical analysis; tap water; temperature; toluene; volatile organic compounds; xylene;     Show all 27 Subjects
Abstract:
... In the present work, the roles of inorganic oxide nanoparticles on the extraction efficiency of polyethylene terephthalate-based nanocomposites were extensively studied. Four fiber coatings based on polyethylene terephthalate nanocomposites containing different types of nanoparticles along with a pristine polyethylene terephthalate polymer were conveniently electrospun on stainless steel wires. Th ...
DOI:
10.1016/j.chroma.2014.11.059

15. Trace analysis of endocrine disrupting compounds in environmental water samples by use of solid-phase extraction and gas chromatography with mass spectrometry detection A

Author:
Azzouz, Abdelmonaim; Ballesteros, Evaristo
Source:
Journal of chromatography 2014 v.1360 pp. 248-257
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; acetonitrile; alkylphenols; bisphenol A; derivatization; detection limit; drinking water; endocrine-disrupting chemicals; gas chromatography-mass spectrometry; groundwater; pH; rivers; silica gel; solid phase extraction; sorbents; statistical analysis; surface water; swimming pools; triclosan; wastewater;     Show all 20 Subjects
Abstract:
... A novel analytical method using a continuous solid-phase extraction system in combination with gas chromatography–mass spectrometry for the simultaneous separation and determination of endocrine disrupting compounds (EDCs) is reported. The method was applied to major EDCs of various types including parabens, alkylphenols, phenylphenols, bisphenol A and triclosan in water. Samples were preconcentra ...
DOI:
10.1016/j.chroma.2014.07.059

16. Three dimensionally honeycomb layered double hydroxides framework as a novel fiber coating for headspace solid-phase microextraction of phenolic compounds A

Author:
Abolghasemi, Mir Mahdi; Yousefi, Vahid
Source:
Journal of chromatography 2014 v.1345 pp. 9-16
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; adsorption; coatings; combs (social insects); desorption; equipment; gas chromatography-mass spectrometry; headspace analysis; hydroxides; mixing; pH; phenolic compounds; polycyclic aromatic hydrocarbons; solid phase microextraction; statistical analysis; temperature; thermal stability;     Show all 17 Subjects
Abstract:
... A new solid phase microextraction (SPME) fiber based on high-temperature three dimensionally honeycomb layered double hydroxide (TDH-LDH) material is presented. The fiber coating can be prepared easily, it is mechanically stable and exhibits relatively high thermal stability. This study shows that three dimensionally honeycomb layered double hydroxide generated porous morphology. The TDH-LDH mater ...
DOI:
10.1016/j.chroma.2014.04.018

17. Keggin-type heteropoly compounds supported on montmorillonite clays offering strong option for efficient solid-phase microextraction coating A

Author:
Abolghasemi, Mir Mahdi; Yousefi, Vahid; Rafiee, Ezzat
Source:
Journal of chromatography 2014 v.1327 pp. 14-18
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; coatings; desorption; equipment; gas chromatography-mass spectrometry; mixing; montmorillonite; nanomaterials; polycyclic aromatic hydrocarbons; solid phase microextraction; stainless steel; statistical analysis; temperature; thermal stability;     Show all 14 Subjects
Abstract:
... Keggin-type heteropoly compounds supported on montmorillonite clays were prepared and used as a highly porous fiber coating material for solid-phase microextraction (SPME). The prepared nanomaterial was immobilized onto a stainless steel wire for fabrication of the SPME fiber. The fiber was evaluated for the extraction of some polycyclic aromatic hydrocarbons (PAHs) from aqueous sample solutions i ...
DOI:
10.1016/j.chroma.2013.12.062

18. Electrospun modified silica-polyamide nanocomposite as a novel fiber coating A

Author:
Bagheri, Habib; Roostaie, Ali
Source:
Journal of chromatography 2014 v.1324 pp. 11-20
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; chlorobenzene; coatings; desorption; detection limit; gas chromatography-mass spectrometry; headspace analysis; models; nanocomposites; nanofibers; nanoparticles; polymers; scanning electron microscopy; silica; solid phase microextraction; stainless steel; temperature;     Show all 17 Subjects
Abstract:
... In the present work, a new solid phase microextraction (SPME) fiber coating based on modified silica-polyamide (PA) nanocomposite was electrospun on a stainless steel wire. Four modified silica-PA nanocomposites together with PA were fabricated by dispersing several typical modified silica nanoparticles in PA polymer solution prior to electrospinning. The surface characteristic of PA nanofibers an ...
DOI:
10.1016/j.chroma.2013.11.024

19. Simultaneous derivatization and ultrasound-assisted dispersive liquid–liquid microextraction of chloropropanols in soy milk and other aqueous matrices combined with gas-chromatography–mass spectrometry

Author:
Carro, A.M.; González, P.; Lorenzo, R.A.
Source:
Journal of chromatography 2013 v.1319 pp. 35-45
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; acetonitrile; beverages; chloroform; cost effectiveness; derivatization; detection limit; experimental design; food safety; fruit juices; gas chromatography-mass spectrometry; liquid-phase microextraction; milk; pH; solvents; soymilk; temperature; wastewater treatment;     Show all 18 Subjects
Abstract:
... A novel approach involving ultrasound-assisted dispersive liquid–liquid microextraction (UA-DLLME) and derivatization combined with gas chromatography–mass spectrometry was developed for the determination of chloropropanols in water and beverages. UA-DLLME was optimized as less solvent-consuming and cost-effective extraction method for water, fruit juice, milk and soy milk samples. The effect of p ...
DOI:
10.1016/j.chroma.2013.10.055

20. Speciation of common volatile halogenated disinfection by-products in tap water under different oxidising agents

Author:
Montesinos, Isabel; Gallego, Mercedes
Source:
Journal of chromatography 2013 v.1310 pp. 113-120
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; byproducts; chlorine; detection limit; disinfection; gas chromatography-mass spectrometry; headspace analysis; nitrates; nitrites; organic matter; sodium sulfate; tap water;     Show all 12 Subjects
Abstract:
... A simple and efficient method has been developed for the extraction and determination of sixteen common volatile halogenated disinfection by-products (DBPs) using the static headspace (HS) technique coupled with gas chromatography–mass spectrometry (GC–MS). The DBPs determined included trihalomethanes (THMs), halonitromethanes (HNMs) and haloacetonitriles (HANs). The extraction parameters (HS cond ...
DOI:
10.1016/j.chroma.2013.08.036