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1. A cadmium(II)-based metal-organic framework material for the dispersive solid-phase extraction of polybrominated diphenyl ethers in environmental water samples A

Author:
Su, Hao; Wang, Ze; Jia, Yuqian; Deng, Liulin; Chen, Xiangfeng; Zhao, Rusong; Chan, T.-W. Dominic
Source:
Journal of chromatography 2015 v.1422 pp. 334-339
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; Fourier transform infrared spectroscopy; cadmium; coordination polymers; detection limit; gas chromatography; ionization; polybrominated diphenyl ethers; response surface methodology; scanning electron microscopy; solid phase extraction; solvents; sorbents; spectrometers; statistical analysis; temperature; thermogravimetry;     Show all 17 Subjects
Abstract:
... In this study, a stable cadmium(II)-based metal-organic framework (MOF) material was designed and used as a sorbent for the dispersive solid-phase extraction (dSPE) of polybrominated diphenyl ethers (PBDEs) in environmental water samples. Gas chromatography coupled with triple quadrupole mass spectrometer (GC–MS/MS), working in the negative chemical ionization mode, was used to quantify the target ...
DOI:
10.1016/j.chroma.2015.10.039

2. A dispersive liquid-liquid microextraction based on solidification of floating organic droplet followed by injector port silylation coupled with gas chromatography–tandem mass spectrometry for the determination of nine bisphenols in bottled carbonated beverages A

Author:
Mandrah, Kapil; Satyanarayana, G.N.V.; Roy, Somendu Kumar
Source:
Journal of chromatography 2017
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; bisphenol A; bisphenol F; bisphenol S; carbonated beverages; derivatization; detection limit; droplets; energy; gas chromatography; liquid-phase microextraction; pH; silylation; solidification; solvents; statistical analysis; tandem mass spectrometry; temperature; India;     Show all 19 Subjects
Abstract:
... In the present study, a method has been efficiently developed for the first time to determine nine bisphenol analogues [bisphenol A (BPA), bisphenol C (BPC), bisphenol AF (BPAF), bisphenol E (BPE), bisphenol F (BPF), bisphenol G (BPG), bisphenol M (BPM), bisphenol S (BPS), and bisphenol Z (BPZ)] together in bottled carbonated beverages (collected from the local market of Lucknow, India) using disp ...
DOI:
10.1016/j.chroma.2017.10.071

3. Analysis of hydrocarbon contamination with membrane-assisted solvent extraction: Comparison of agitation and sonication methods

Author:
Szekeres, Z.; Eke, Zs.; Rikker, T.; Torkos, K.
Source:
Journal of chromatography 2009 v.1216 no.41 pp. 6964-6969
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; agitation; chromatography; diesel fuel; evaporation; gasoline; hexane; methanol; solvents; temperature; water pollution;     Show all 11 Subjects
Abstract:
... Membrane-assisted solvent extraction (MASE) coupled to large volume injection was applied to the determination of (gasoline-type) hydrocarbon contamination in water samples. Hexane was used as acceptor phase. 50μL extract was injected in the programmed temperature vaporizer injector using combined split-splitless evaporation. The extraction conditions were optimized both for MASE with agitation an ...
DOI:
10.1016/j.chroma.2009.08.048

4. Analysis of malondialdehyde in human plasma samples through derivatization with 2,4-dinitrophenylhydrazine by ultrasound-assisted dispersive liquid–liquid microextraction-GC-FID approach

Author:
Malaei, Reyhane; Ramezani, Amir M.; Absalan, Ghodratollah
Source:
Journal of chromatography 2018 v.1089 pp. 60-69
ISSN:
1570-0232
Subject:
ionic strength,   etc   ; Food and Drug Administration; biomarkers; centrifugation; chromatography; derivatization; detection limit; guidelines; humans; hydrazones; liquid-phase microextraction; malondialdehyde; pH; solvents; sonication; temperature; ultrasonic treatment;     Show all 17 Subjects
Abstract:
... A sensitive and reliable ultrasound-assisted dispersive liquid–liquid microextraction (UA-DLLME) procedure was developed and validated for extraction and analysis of malondialdehyde (MDA) as an important lipids-peroxidation biomarker in human plasma. In this methodology, to achieve an applicable extraction procedure, the whole optimization processes were performed in human plasma. To convert MDA i ...
DOI:
10.1016/j.jchromb.2018.05.001

5. Application of affinity capillary electrophoresis and density functional theory to the investigation of benzo-18-crown-6-ether complex with ammonium cation

Author:
Ehala, Sille; Toman, Petr; Makrlík, Emanuel; Kašička, Václav
Source:
Journal of chromatography 2009 v.1216 no.45 pp. 7927-7931
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; ammonium compounds; capillary electrophoresis; chromatography; electrolytes; hydrogen bonding; oxygen; regression analysis; solvents; temperature;     Show all 10 Subjects
Abstract:
... Affinity capillary electrophoresis (ACE) and quantum mechanical density functional theory (DFT) calculations have been employed for investigation of non-covalent interactions between macrocyclic ligand, benzo-18-crown-6-ether (B18C6) and ammonium cation, NH₄ ⁺. Firstly, by means of ACE, the strength of the B18C6-NH₄ ⁺ complex in mixed binary hydro-organic solvent system, methanol-water (50/50, v/v ...
DOI:
10.1016/j.chroma.2009.09.034

6. Application of ceramic/carbon composite as a novel coating for solid-phase microextraction

Author:
Zeng, Jingbin; Yu, Binbin; Chen, Wenfeng; Lin, Zhijie; Zhang, Limei; Lin, Zequan; Chen, Xi; Wang, Xiaoru
Source:
Journal of chromatography 2008 v.1188 no.1 pp. 26-33
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; carbon; ceramics; chlorpyrifos; coatings; desorption; detection limit; ethion; gas chromatography; mechanical properties; mixing; pirimiphos-methyl; quinalphos; scanning electron microscopy; solid phase microextraction; solvents; stainless steel; temperature;     Show all 18 Subjects
Abstract:
... A ceramic/carbon composite was developed and applied as a novel coating for solid-phase microextraction (SPME). The ceramic/carbon coating exhibited several good properties for SPME, such as high extraction quantities and enhanced thermal and organic solvent stability. Under scanning electron microscopy (SEM), the tightly attached coating layer on stainless steel wire revealed excellent mechanical ...
DOI:
10.1016/j.chroma.2007.08.017

7. Application of headspace single-drop microextraction coupled with gas chromatography for the determination of short-chain fatty acids in RuO₄ oxidation products of asphaltenes

Author:
Li, Yun; Xiong, Yongqiang; Liang, Qianyong; Fang, Chenchen; Wang, Chunjiang
Source:
Journal of chromatography 2010 v.1217 no.22 pp. 3561-3566
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; agitation; gas chromatography; headspace analysis; ionization; microextraction; mixing; oxidation; ruthenium; short chain fatty acids; sodium chloride; solvents; temperature;     Show all 13 Subjects
Abstract:
... In this study, headspace single-drop microextraction (HS-SDME) coupled with gas chromatography-flame ionization detection (GC-FID), was employed to determine short-chain fatty acids (SCFAs) in ruthenium tetroxide (RuO₄) oxidation products of asphaltenes. Several significant parameters, such as drop solvent type, drop volume, sample solution ionic strength, agitation speed, extraction time, and rat ...
DOI:
10.1016/j.chroma.2010.03.041

8. Application of non-ionic surfactant as a developed method for the enhancement of two-phase solvent bar microextraction for the simultaneous determination of three phthalate esters from water samples A

Author:
Bandforuzi, Samereh Ranjbar; Hadjmohammadi, Mohammad Reza
Source:
Journal of chromatography 2018 v.1561 pp. 39-47
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; detection limit; dibutyl phthalate; diethyl phthalate; drinking water; high performance liquid chromatography; hydrophobicity; micelles; microextraction; mixing; nonionic surfactants; pH; solvents; temperature;     Show all 14 Subjects
Abstract:
... The extraction of phthalate esters (PEs) from aqueous matrices using two-phase solvent bar microextraction by organic micellar phase was investigated. A short hollow fiber immobilized with reverse micelles of Brij 35 surfactant in 1-octanol was served as the solvent bar for microextraction. Experimental results show that the extraction efficiency were much higher using two-phase solvent bar microe ...
DOI:
10.1016/j.chroma.2018.05.039

9. Application of ultrasound-assisted emulsification microextraction based on applying low-density organic solvent for the determination of organochlorine pesticides in water samples

Author:
Zhang, Yufeng; Lee, Hian Kee
Source:
Journal of chromatography 2012 v.1252 pp. 67-73
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; aqueous solutions; centrifugation; cost effectiveness; detection limit; dieldrin; emulsifying; emulsions; endrin; gas chromatography-mass spectrometry; heptachlor; hexachlorobenzene; iso-octanes; microextraction; pesticide residues; polyethylene; rivers; solvents; tap water; temperature; ultrasonics; water pollution;     Show all 22 Subjects
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 ...
DOI:
10.1016/j.chroma.2012.06.065

10. Characterization of carboxylic acids in atmospheric aerosols using hydrophilic interaction liquid chromatography tandem mass spectrometry

Author:
Kitanovski, Zoran; Grgić, Irena; Veber, Marjan
Source:
Journal of chromatography 2011 v.1218 no.28 pp. 4417-4425
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; acetonitrile; aerosols; ammonium acetate; detection limit; electrospray ionization mass spectrometry; hydrophilic interaction chromatography; isomers; monitoring; pH; phthalic acid; pyruvic acid; solvents; tandem mass spectrometry; temperature;     Show all 15 Subjects
Abstract:
... A sensitive hydrophilic interaction liquid chromatography/electrospray ionization mass spectrometry (HILIC/ESI-MS/MS) method was developed for determination of selected aliphatic (i.e. malonic, succinic, glutaric, adipic, pimelic, suberic, azelaic, maleic, fumaric, glycolic and pyruvic acid), alicyclic (i.e. cis-pinonic and pinic acid) and aromatic (i.e. trimesic, phthalic acid and its isomers) ca ...
DOI:
10.1016/j.chroma.2011.05.020

11. Chemometric assisted solid-phase microextraction for the determination of anti-inflammatory and antiepileptic drugs in river water by liquid chromatography-diode array detection

Author:
Vera-Candioti, L.; Gil García, M.D.; Martínez Galera, M.; Goicoechea, H.C.
Source:
Journal of chromatography 2008 v.1211 no.1-2 pp. 22-32
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; anti-inflammatory activity; anticonvulsants; chemometrics; desorption; detection limit; indomethacin; ketoprofen; liquid chromatography; mixing; pH; river water; screening; soaking; solid phase microextraction; solvents; temperature; uncertainty;     Show all 18 Subjects
Abstract:
... In the present work, an analytical method for the simultaneous determination of seven non steroidal anti-inflammatory drugs (naproxen, ketoprofen, diclofenac, piroxicam, indomethacin, sulindac and diflunisal) and the anticonvulsant carbamazepine is reported. The method involves preconcentration and clean-up by solid-phase microextraction using polydimethylsiloxane/divinylbenzene fibers, followed b ...
DOI:
10.1016/j.chroma.2008.09.093

12. 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

13. Determination of cocaine in postmortem human liver exposed to overdose. Application of an innovative and efficient extraction/clean up procedure and gas chromatography–mass spectrometry analysis

Author:
Magalhães, Elisângela Jaqueline; Queiroz, Maria Eliana Lopes Ribeiro de; Penido, Marcus Luiz de Oliveira; Paiva, Marco Antônio Ribeiro; Teodoro, Janaína Aparecida Reis; Augusti, Rodinei; Nascentes, Clésia Cristina
Source:
Journal of chromatography 2013 v.1309 pp. 15-21
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; acetonitrile; cattle; cocaine; gas chromatography-mass spectrometry; humans; liver; overdose; pH; sodium chloride; solvents; temperature;     Show all 12 Subjects
Abstract:
... A simple and efficient method was developed for the determination of cocaine in post-mortem samples of human liver via solid–liquid extraction with low temperature partitioning (SLE–LTP) and analysis by gas chromatography coupled to mass spectrometry (GC–MS). The extraction procedure was optimized by evaluating the influence of the following variables: pH of the extract, volume and composition of ...
DOI:
10.1016/j.chroma.2013.08.039

14. Determination of organophosphorus pesticides and metabolites in cereal-based baby foods and wheat flour by means of ultrasound-assisted extraction and hollow-fiber liquid-phase microextraction prior to gas chromatography with nitrogen phosphorus detection

Author:
González-Curbelo, Miguel Ángel; Hernández-Borges, Javier; Borges-Miquel, Teresa María; Rodríguez-Delgado, Miguel Ángel
Source:
Journal of chromatography 2013 v.1313 pp. 166-174
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; European Union; acetonitrile; desorption; detection limit; evaporation; formic acid; gas chromatography; infant foods; liquid-phase microextraction; maximum residue limits; metabolites; mixing; nitrogen; organophosphorus pesticides; pH; phosphorus; sodium chloride; solvents; temperature; wheat flour;     Show all 21 Subjects
Abstract:
... A new method based on hollow-fiber liquid-phase microextraction (HF-LPME) has been developed for the determination of a group of organophosphorus pesticides, including some of their metabolites, in two commercial cereal-based baby foods and one wheat flour prior to gas chromatography-nitrogen phosphorus detection. Samples were first extracted by ultrasound-assisted extraction with acetonitrile (AC ...
DOI:
10.1016/j.chroma.2013.05.081

15. Development of a method for the determination of UV filters in water samples using stir bar sorptive extraction and thermal desorption-gas chromatography-mass spectrometry

Author:
Rodil, Rosario; Moeder, Monika
Source:
Journal of chromatography 2008 v.1179 no.2 pp. 81-88
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; correlation; desorption; detection limit; extraction; gas chromatography; lakes; mass spectrometry; pH; reproducibility; river water; solvents; temperature; ultraviolet radiation; wastewater; water analysis; water filters;     Show all 17 Subjects
Abstract:
... Stir bar sorptive extraction (SBSE) in combination with thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) was applied for the determination of 9 UV filters in water samples. The stir bar coated with polydimethylsiloxane (PDMS) was added to 20mL of water sample at pH 2 (10% MeOH) and stirred at 1000rpm for 180min. Then, the stir bar was subjected to TD-GC-MS. The desorption conditi ...
DOI:
10.1016/j.chroma.2007.11.090

16. Development of an ultrasound-assisted emulsification–microextraction method for the determination of the main compounds causing cork taint in wines

Author:
Pizarro, C.; Sáenz-González, Cristina; Pérez-del-Notario, Nuria; González-Sáiz, José María
Source:
Journal of chromatography 2012 v.1229 pp. 63-71
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; chromatography; cork; correlation; detection limit; experimental design; pentachlorophenol; solvents; taint; temperature; ultrasonic treatment; wines;     Show all 12 Subjects
Abstract:
... In this work, an ultrasound-assisted emulsification–microextraction method has been optimised for the determination in wine of haloanisoles (2,4,6-trichloranisole (TCA), 2,3,4,6-tetrachloroanisole (TeCA), 2,4,6-tribromoanisole (TBA) and pentachloranisole (PCA)) responsible for the so-called cork taint. Their halophenolic precursors (2,4,6-trichlorophenol (TCP), 2,3,4,6-tetrachlorophenol (TeCP), 2, ...
DOI:
10.1016/j.chroma.2012.01.033

17. Development of multiwalled carbon nanotubes based micro-solid-phase extraction for the determination of trace levels of sixteen polycyclic aromatic hydrocarbons in environmental water samples

Author:
Guo, Liang; Lee, Hian Kee
Source:
Journal of chromatography 2011 v.1218 no.52 pp. 9321-9327
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; United States Environmental Protection Agency; agitation; carbon nanotubes; desorption; detection limit; gas chromatography-mass spectrometry; polycyclic aromatic hydrocarbons; polypropylenes; river water; solvents; temperature; ultrasonic treatment;     Show all 13 Subjects
Abstract:
... Micro-solid-phase extraction (μ-SPE) was developed for the determination of trace level of 16 United States Environmental Protection Agency priority polycyclic aromatic hydrocarbons (PAHs) in river water samples with gas chromatography–mass spectrometry (GC–MS). In the μ-SPE device, multiwalled carbon nanotubes was employed as sorbent and was packed inside an porous polypropylene membrane “envelop ...
DOI:
10.1016/j.chroma.2011.10.066

18. Effects of the operation parameters on Hydrophilic Interaction Liquid Chromatography separation of phenolic acids on zwitterionic monolithic capillary columns

Author:
Škeříková, Veronika; Jandera, Pavel
Source:
Journal of chromatography 2010 v.1217 no.51 pp. 7981-7989
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; acetates; acetonitrile; beers; hydrophilic interaction chromatography; methanol; phenolic acids; polymerization; solvents; temperature; thermal stability; zwitterions;     Show all 12 Subjects
Abstract:
... Strongly polar phenolic acids are weakly retained and often poorly separated in reversed-phase (RP) liquid chromatography. We prepared zwitterionic polymethacrylate monolithic columns for micro-HPLC by in situ co-polymerization in fused-silica capillaries. The capillary monolithic columns prepared under optimized polymerization conditions show some similarities with the conventional particulate co ...
DOI:
10.1016/j.chroma.2010.07.061

19. Headspace hollow fiber protected liquid-phase microextraction combined with gas chromatography–mass spectroscopy for speciation and determination of volatile organic compounds of selenium in environmental and biological samples

Author:
Ghasemi, Ensieh; Sillanpää, Mika; Najafi, Nahid Mashkouri
Source:
Journal of chromatography 2011 v.1218 no.3 pp. 380-386
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; detection limit; equations; experimental design; gas chromatography-mass spectrometry; headspace analysis; liquid-phase microextraction; mixing; screening; selenium; solvents; temperature; volatile organic compounds;     Show all 13 Subjects
Abstract:
... A simple and novel speciation method for the determination of volatile organic compounds of selenium (dimethylselenide (DMSe) and dimethyldiselenide (DMDSe) has been developed using a headspace hollow fiber protected liquid-phase microextraction (HS-HF-LPME) combined with capillary gas chromatography–mass spectrometry (GC–MS). The organic solvent impregnated in the pores and filled inside the poro ...
DOI:
10.1016/j.chroma.2010.12.005

20. Hollow fiber-based liquid-liquid-liquid microextraction combined with electrospray ionization-ion mobility spectrometry for the determination of pentazocine in biological samples

Author:
Saraji, Mohammad; Jafari, Mohammad Taghi; Sherafatmand, Hossein
Source:
Journal of chromatography 2010 v.1217 no.32 pp. 5173-5178
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; chromatography; detection limit; liquid-phase microextraction; solvents; spectroscopy; temperature; urine;     Show all 8 Subjects
Abstract:
... A new method based on liquid-liquid-liquid microextraction combined with electrospray ionization-ion mobility spectrometry (LLLME-ESI-IMS) was used for the determination of pentazocine in urine and plasma samples. Experimental parameters which control the performance of LLLME, such as selection of composition of donor and acceptor phase, type of organic solvent, ionic strength of the sample, extra ...
DOI:
10.1016/j.chroma.2010.06.035