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1. 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

2. Amino-modified covalent organic framework as solid phase extraction absorbent for determination of carboxylic acid pesticides in environmental water samples

Author:
Ji, Wen-Hua; Guo, Yu-Shuang; Wang, Xiao; Lu, Xiao-Fan; Guo, Dian-Shun
Source:
Journal of chromatography 2019 v.1595 pp. 11-18
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; absorbents; absorption; carboxylic acids; desorption; high performance liquid chromatography; hydrophilicity; pH; pesticides; scanning electron microscopy; solid phase extraction; solvents; surface area;     Show all 16 Subjects
Abstract:
... The amino-modified covalent organic framework (NH2@COF) was synthesized via the thiol-ene click reaction of vinyl covalent organic framework (COF) with 4-aminobenzenethiol. The introduction of amino groups can interact with the anionic headgroup of carboxylic acid pesticides. Moreover, ample hydrophilic surface area can boost absorption in the water media. The NH2@COF was fully characterized by Fo ...
DOI:
10.1016/j.chroma.2019.02.048

3. 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

4. Analysis of phenolic pollutants in human samples by high performance capillary electrophoresis based on pretreatment of ultrasound-assisted emulsification microextraction and solidification of floating organic droplet

Author:
Wang, Huili; Yan, Hao; Wang, Chengjun; Chen, Fan; Ma, Meiping; Wang, Wenwei; Wang, Xuedong
Source:
Journal of chromatography 2012 v.1253 pp. 16-21
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; 2,4-dichlorophenol; ambient temperature; blood; capillary electrophoresis; centrifugation; chromatography; correlation; detection limit; emulsifying; humans; ice; microextraction; pH; pentachlorophenol; pollutants; rapid methods; solidification; solvents; ultrasonics; urine;     Show all 21 Subjects
Abstract:
... A novel, simple and rapid method, termed ultrasound-assisted emulsification microextraction and solidification of floating organic droplet (UAEM–SFO) coupled to high performance capillary electrophoresis (HPCE), was developed for preconcentration and analysis of five phenolic compounds (PCs) in human urine and blood samples. The proposed method is based on microextraction of target analytes in les ...
DOI:
10.1016/j.chroma.2012.06.088

5. A new anionic exchange stir bar sorptive extraction coating based on monolithic material for the extraction of inorganic anion

Author:
Huang, Xiaojia; Lin, Jianbing; Yuan, Dongxing
Source:
Journal of chromatography 2010 v.1217 no.30 pp. 4898-4903
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; anions; bromides; chromatography; coatings; desorption; detection limit; infrared spectroscopy; nitrates; pH; phosphates; scanning electron microscopy; solutes; solvents; trademarks;     Show all 15 Subjects
Abstract:
... A novel anionic exchange stir bar sorptive extraction (SBSE) coating based on poly(2-(methacryloyloxy)ethyltrimethylammonium chloride-co-divinylbenzene) monolithic material for the extraction of inorganic anion was prepared. The effect of preparation conditions such as ratio of functional monomer to cross-linker, content of porogenic solvent on the extraction efficiencies were investigated in deta ...
DOI:
10.1016/j.chroma.2010.05.063

6. A new strategy to simultaneous microextraction of acidic and basic compounds

Author:
Moradi, Morteza; Yamini, Yadollah; Kakehmam, Jamal; Esrafili, Ali; Ghambarian, Mahnaz
Source:
Journal of chromatography 2011 v.1218 no.26 pp. 3945-3951
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; chromatography; detection limit; emulsifiers; emulsifying; ionization; mass transfer; microextraction; molecular weight; pH; pollutants; solvents; surfactants;     Show all 13 Subjects
Abstract:
... The simultaneous extraction of acidic and basic pollutants from water samples is an interesting and debatable work in sample preparation techniques. A novel and efficient method named ion pair based surfactant assisted microextraction (IP-SAME) was applied for extraction and preconcentration of five selected acidic and basic aromatic species as model compounds in water samples, followed by high pe ...
DOI:
10.1016/j.chroma.2011.04.060

7. An innovative method for synthesis of imprinted polymer nanomaterial holding thiamine (vitamin B1) selective sites and its application for thiamine determination in food samples B Analytical technologies in the biomedical and life sciences

Author:
Alizadeh, Taher; Akhoundian, Maedeh; Ganjali, Mohammad Reza
Source:
Journal of chromatography 2018 v.1084 pp. 166-174
ISSN:
1570-0232
Subject:
ionic strength,   etc   ; Fourier transform infrared spectroscopy; binding capacity; chloroform; chromatography; fluorometry; hydrophilicity; models; nanomaterials; pH; polymerization; polymers; scanning electron microscopy; solvents; sorption isotherms; thiamin; zeta potential;     Show all 17 Subjects
Abstract:
... Thiamine is a highly hydrophilic vitamin which is insoluble in common organic solvents, utilized traditionally for synthesis of molecularly imprinted polymer. In this work a simple strategy is introduced to overcome the insolubility problem of thiamine and prepare an efficient MIP in chloroform. Thiamine, as a cationic agent, involved in an ion-pair complex with anionic species of trimethylsilyl-p ...
DOI:
10.1016/j.jchromb.2018.03.036

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. A study of thin film solid phase microextraction methods for analysis of fluorinated benzoic acids in seawater A

Author:
Boyacı, Ezel; Goryński, Krzysztof; Viteri, C. Ricardo; Pawliszyn, Janusz
Source:
Journal of chromatography 2016 v.1436 pp. 51-58
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; benzoic acids; derivatization; desorption; gas chromatography; industry; liquid chromatography; mass spectrometry; oils; pH; petroleum; seawater; solid phase microextraction; solvents; tracer techniques;     Show all 15 Subjects
Abstract:
... Fluorinated benzoic acids (FBAs) are frequently used as tracers by the oil industry to characterize petroleum reservoirs. The demand for fast, reliable, robust, and sensitive approaches to separate and quantify FBAs in produced water, both in laboratory and field conditions, has not been yet fully satisfied. In this study, for the first time, thin film solid phase microextraction (TF-SPME) is prop ...
DOI:
10.1016/j.chroma.2016.01.071

10. A two level hierarchical model of protein retention in ion exchange chromatography A

Author:
Salvalaglio, Matteo; Paloni, Matteo; Guelat, Bertrand; Morbidelli, Massimo; Cavallotti, Carlo
Source:
Journal of chromatography 2015 v.1411 pp. 50-62
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; Gibbs free energy; chymotrypsinogen; ion exchange chromatography; lysozyme; models; molecular dynamics; pH; prediction; protein structure; proteins; solvents; van der Waals forces;     Show all 13 Subjects
Abstract:
... Predicting protein retention in ion exchange chromatography (IEX) from first principles is a fascinating perspective. In this work a two level hierarchical modeling strategy is proposed in order to calculate protein retention factors. Model predictions are tested against experimental data measured for Lysozyme and Chymotrypsinogen A in IEX columns as a function of ionic strength and pH. At the hig ...
DOI:
10.1016/j.chroma.2015.07.101

11. Capabilities of mixed-mode liquid chromatography coupled to inductively coupled plasma mass spectrometry for the simultaneous speciation analysis of inorganic and organically-bound selenium

Author:
Peachey, Emma; Cook, Ken; Castles, Adrian; Hopley, Christopher; Goenaga-Infante, Heidi
Source:
Journal of chromatography 2009 v.1216 no.42 pp. 7001-7006
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; anion exchange; arsenic; arsenites; biogeography; biological speciation; citrates; detection limit; enzymatic hydrolysis; high performance liquid chromatography; leaching; mass spectrometry; methylselenocysteine; monitoring; pH; selenium; selenomethionine; solvents; watercress;     Show all 19 Subjects
Abstract:
... This work investigates for the first time the potential of mixed-mode (anion-exchange with reversed-phase) high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) for the simultaneous retention and selective separation of a range of inorganic and organically-bound selenium (Se) species. Baseline separation and detection of selenocystine (SeCys₂), Se- ...
DOI:
10.1016/j.chroma.2009.08.047

12. Carbon coated magnetic nanoparticles as a novel magnetic solid phase extraction adsorbent for simultaneous extraction of methamphetamine and ephedrine from urine samples B Analytical technologies in the biomedical and life sciences

Author:
Taghvimi, Arezou; Hamishehkar, Hamed
Source:
Journal of chromatography 2017 v.1041-1042 pp. 113-119
ISSN:
1570-0232
Subject:
ionic strength,   etc   ; Fourier transform infrared spectroscopy; X-ray diffraction; adsorbents; agitation; carbon; chromatography; desorption; ephedrine; forensic sciences; nanoparticles; pH; scanning electron microscopy; solid phase extraction; solvents; urine;     Show all 16 Subjects
Abstract:
... This paper develops a highly selective, specific and efficient method for simultaneous determination of ephedrine and methamphetamine by a new carbon coated magnetic nanoparticles (C/MNPs) as a magnetic solid phase extraction (MSPE) adsorbent in biological urine medium. The characterization of synthesized magnetic nano adsorbent was completely carried out by various characterization techniques lik ...
DOI:
10.1016/j.jchromb.2016.11.039

13. 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

14. 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

15. Comparison of peak shape in hydrophilic interaction chromatography using acidic salt buffers and simple acid solutions A

Author:
Heaton, James C.; Russell, Joseph J.; Underwood, Tim; Boughtflower, Robert; McCalley, David V.
Source:
Journal of chromatography 2014 v.1347 pp. 39-48
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; ammonium; buffers; formates; formic acid; hydrophilic interaction chromatography; ionization; pH; phosphoric acid; silica; solutes; solvents;     Show all 12 Subjects
Abstract:
... The retention and peak shape of neutral, basic and acidic solutes was studied on hydrophilic interaction chromatography (HILIC) stationary phases that showed both strong and weak ionic retention characteristics, using aqueous–acetonitrile mobile phases containing either formic acid (FA), ammonium formate (AF) or phosphoric acid (PA). The effect of organic solvent concentration on the results was a ...
DOI:
10.1016/j.chroma.2014.04.026

16. 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

17. 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

18. Determination of estrogenic mycotoxins in environmental water samples by low-toxicity dispersive liquid–liquid microextraction and liquid chromatography–tandem mass spectrometry A

Author:
Emídio, Elissandro Soares; da Silva, Claudia Pereira; de Marchi, Mary Rosa Rodrigues
Source:
Journal of chromatography 2015 v.1391 pp. 1-8
ISSN:
0021-9673
Subject:
ionic strength,   etc   ; centrifugation; detection limit; ionization; liquid chromatography; liquid-phase microextraction; liquids; pH; river water; solvents; statistical analysis; tandem mass spectrometry; zearalenol; zearalenone;     Show all 14 Subjects
Abstract:
... A novel, simple, rapid and eco-friendly method based on dispersive liquid–liquid microextraction using a bromosolvent was developed to determine six estrogenic mycotoxins (zearalenone, zearalanone, α-zearalanol, β-zearalanol, α-zearalenol and β-zearalenol) in water samples by liquid chromatography–electrospray ionization tandem mass spectrometry in the negative mode (LC–ESI–MS/MS). The optimal con ...
DOI:
10.1016/j.chroma.2015.02.067

19. 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

20. Determination of three tetracyclines in bovine milk using magnetic solid phase extraction in tandem with dispersive liquid-liquid microextraction coupled with HPLC

Author:
Al-Afy, Nour; Sereshti, Hassan; Hijazi, Akram; Rashidi Nodeh, Hamid
Source:
Journal of chromatography 2018 v.1092 pp. 480-488
ISSN:
1570-0232
Subject:
ionic strength,   etc   ; Fourier transform infrared spectroscopy; adsorbents; beta-cyclodextrin; desorption; detection limit; doxycycline; energy-dispersive X-ray analysis; graphene oxide; high performance liquid chromatography; liquid-phase microextraction; magnetism; milk; oxytetracycline; pH; scanning electron microscopy; solid phase extraction; solvents; zeta potential;     Show all 19 Subjects
Abstract:
... A novel analytical method namely magnetic solid phase extraction in tandem with dispersive liquid-liquid microextraction was developed and used for the extraction/preconcentration of tetracycline (TCN), oxytetracycline (OTC) and doxycycline (DC) from bovine milk sample before HPLC-UV analysis. The β-cyclodextrin functionalized silica-coated magnetic graphene oxide (Fe3O4@SiO2@GO-β-CD) was used as ...
DOI:
10.1016/j.jchromb.2018.06.049