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You searched for: Subject term derivatization Remove constraint Subject term: derivatization Subject term acidification Remove constraint Subject term: acidification
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1. Atmospheric degradation of industrial fluorinated acrylates and methacrylates with Cl atoms at atmospheric pressure and 298 K

Author:
Cynthia B. Rivela; María B. Blanco; Mariano A. Teruel
Source:
Atmospheric environment 2018 v.178 pp. 206-213
ISSN:
1352-2310
Subject:
acidification; acrylates; atmospheric chemistry; atmospheric pressure; chlorine; derivatization; esters; flame ionization; formaldehyde; gas chromatography-mass spectrometry; gases; global warming; hydroxylamine; ozone; photochemistry; solid phase microextraction
Abstract:
... The gas-phase reaction of Cl atom with 2,2,2-trifluoroethylacrylate (k1), 1,1,1,3,3,3-hexafluoroisopropylacrylate (k2), 2,2,2-trifluoroethylmethacrylate (k3) and 1,1,1,3,3,3-hexafluoroisopropylmethacrylate (k4), have been investigated at 298 K and 1 atm using the relative method by gas chromatography coupled with flame ionization detection (GC-FID). The values obtained are (in cm3 molecule−1 s−1): ...
DOI:
10.1016/j.atmosenv.2018.01.055

2. Automated pre-column derivatization with 9-xanthydrol for the determination of ethyl carbamate in food matrices by high performance liquid chromatography with fluorimetric detection

Author:
Daniel Antonio Aguilera Ojeda; Kazimierz Wrobel; Alma Rosa Corrales Escobosa; Luis Fernando Mejia Diaz; Katarzyna Wrobel
Source:
Journal of food measurement & characterization 2019 v.13 no.4 pp. 2722-2728
ISSN:
2193-4126
Subject:
acidification; automation; derivatization; detection limit; ethyl carbamate; fluorometry; food matrix; high performance liquid chromatography; perchloric acid; red wines; soy sauce
Abstract:
... In this work, derivatization of ethyl carbamate (EC) with 9-xanthydrol prior to liquid chromatography with fluorimetric detection (HPLC-FLD) was revisited, focusing on refining the reaction conditions and on automation. Perchloric acid was used for sample acidification and a sequence of operations was defined to perform the reaction in the autosampler needle. Chromatographic separation together wi ...
DOI:
10.1007/s11694-019-00193-6

3. Determination of Lewisites and their hydrolysis products in aqueous and multiphase samples by in-sorbent tube butyl thiolation followed by thermal desorption–gas chromatography–full scan mass spectrometry

Author:
Oliver Terzic; Sandra Bartenbach; Pim de Voogt
Source:
Journal of chromatography 2013 v.1304 no. pp. 34-41
ISSN:
0021-9673
Subject:
acidification; air; decontamination; derivatization; detection limit; equipment; forensic sciences; gas chromatography; hydrolysis; liquid-liquid extraction; mass spectrometry; wastes
Abstract:
... A rapid, sensitive and robust method for determining the chemical warfare agents Lewisites and their hydrolysis products in aqueous and multiphase sample matrices has been developed as an extension of the previous work (Terzic, 2010 [32]). In the new method, the acidification of the sample and use of 1-butanethiol derivatisation instead of trimethylsilylation significantly improved both, qualitati ...
DOI:
10.1016/j.chroma.2013.06.068

4. Determination of UV-327 and its metabolites in human urine using dispersive liquid-liquid microextraction and gas chromatography-tandem mass spectrometry

Author:
Corinna Fischer; Thomas Göen
Source:
Analytical methods 2021 v.13 no.35 pp. 3978-3986
ISSN:
1759-9679
Subject:
acidification; chemical species; chloroform; derivatization; enzymatic hydrolysis; humans; hydrochloric acid; isopropyl alcohol; liquid-phase microextraction; metabolism; metabolites; pH; sodium chloride; solvents; stabilizers; tandem mass spectrometry; triazoles; urine
Abstract:
... The benzotriazole UV stabilizer (BUVS) 2-(5-chloro-benzotriazol-2-yl)-4,6-di-(tert-butyl)phenol (UV-327) is added to plastic materials for UV protection. The compound is known to be ubiquitously distributed in the environment. We developed the first analytical method for the determination of UV-327 and seven metabolites, which were identified in vitro, in urine to be able to investigate the in viv ...
DOI:
10.1039/d1ay00932j

5. Determination of acetone in seawater using derivatization solid-phase microextraction

Author:
Hudson, Edward D.; Okuda, Kadek; Ariya, Parisa A.
Source:
Analytical and bioanalytical chemistry 2007 v.388 no.5-6 pp. 1275-1282
ISSN:
1618-2642
Subject:
acetone; acidification; buffering capacity; derivatization; detection limit; gas chromatography-mass spectrometry; pH; saline water; seawater; solid phase microextraction; troposphere; Arctic region
Abstract:
... Acetone plays an important role in the chemistry of both the atmosphere and the ocean, due to its potential effect on the tropospheric HOx (= HO + HO₂) budget, as well as its environmental and health effects. We discuss the development of a mobile, sensitive, selective, economical and facile method for the determination of acetone in seawater. The method consists of derivatizing acetone to its pen ...
DOI:
10.1007/s00216-007-1324-x

6. Determination of endogenous GHB levels in chest and pubic hair

Author:
Elisabetta Bertol; Francesco Mari; Alessio Lachi; Giusy Tespio; Fabio Vaiano
Source:
Forensic science international 2021 v.325 pp. 110857
ISSN:
0379-0738
Subject:
acidification; chest; derivatization; ethyl acetate; forensic sciences; gas chromatography-mass spectrometry; gender; hairs; keratin; regression analysis; t-test
Abstract:
... Endogenous nature of GHB represents a critical issue for forensic toxicologists, especially in alleged sexual assaults. Therefore, discrimination between physiologically and additional amounts from exogenous sources of such a substance must be effective and reliable in order to avoid severe misinterpretation. This study aimed to quantify the GHB baseline concentrations in chest and pubic hairs col ...
DOI:
10.1016/j.forsciint.2021.110857

7. Determination of epoxides by high-performance liquid chromatography following derivatization with N,N-diethyldithiocarbamate

Author:
Dupard-Julien, Catrina L.; Kandlakunta, Bhaskarachary; Uppu, Rao M.
Source:
Analytical and bioanalytical chemistry 2007 v.387 no.3 pp. 1027-1032
ISSN:
1618-2642
Subject:
acetonitrile; acidification; alkenes; carbon disulfide; cell culture; derivatization; epoxides; esters; fetal bovine serum; molecular weight; pH; reversed-phase high performance liquid chromatography; ultrafiltration; water flow
Abstract:
... A reversed-phase, high-performance liquid chromatography (RP-HPLC) method that allows quantitation of low levels of epoxides has been described. The method involved derivatization of epoxides using 100- to 1,000-fold excess N,N-diethyldithiocarbamate (DTC) at 60 °C for 20 min at neutral pH. The unreacted DTC was then decomposed to CS₂ and diethyl amine by acidification of the reaction mixture to p ...
DOI:
10.1007/s00216-006-1003-3
PubMed:
17205273

8. Determination of glyphosate, AMPA and glufosinate in dairy farm water from Argentina using a simplified UHPLC-MS/MS method

Author:
Luisina Delma Demonte; Nicolás Michlig; Monica Gaggiotti; Claudia Guadalupe Adam; Horacio Ramón Beldoménico; Maria Rosa Repetti
Source:
Science of the total environment 2018 v.645 pp. 34-43
ISSN:
0048-9697
Subject:
acidification; dairy farming; derivatization; farms; glufosinate; glyphosate; liquid chromatography; livestock; mass spectrometry; methylene chloride; monitoring; neutralization; risk analysis; tanks; wells; Argentina; Brazil; United States
Abstract:
... Argentina, together with the USA and Brazil, produces approximately 80% of the total worldwide glyphosate loadings. The development of a simplified ultra-high performance liquid chromatographic tandem mass spectrometric method (UHPLC-MS/MS) for the determination of glyphosate, aminomethylphosphonic acid (AMPA) and glufosinate in water is described, including studies of several alternatives of 9-fl ...
DOI:
10.1016/j.scitotenv.2018.06.340

9. Development and Validation of a High-Performance Liquid Chromatography Method for the Determination of Histamine in Fish Samples Using Fluorescence Detection with Pre-column Derivatization

Author:
Ayoub Kounnoun; Mohamed EL Maadoudi; Francesco Cacciola; Luigi Mondello; Hajar Bougtaib; Naoual Alahlah; Nadia Amajoud; Aicha EL Baaboua; Adnane Louajri
Source:
Chromatographia 2020 v.83 no.7 pp. 893-901
ISSN:
0009-5893
Subject:
acidification; beta-mercaptoethanol; derivatization; detection limit; fish; fluorescence; food industry; high performance liquid chromatography; histamine; humans; ion exchange; perchloric acid; solid phase extraction
Abstract:
... Histamine level determination in fish and fish products is important for human safety, fish quality and food industry. For this reason, a rapid, robust, and precise method is needed. To achieve this objective, an HPLC method with fluorescence detection was developed and validated. Histamine in fish samples was efficiently extracted with perchloric acid, and purified with ion-exchange solid-phase e ...
DOI:
10.1007/s10337-020-03909-9

10. Development and validation of a GC-FID method for the analysis of short chain fatty acids in rat and human faeces and in fermentation fluids

Author:
Serena Scortichini; Maria Chiara Boarelli; Stefania Silvi; Dennis Fiorini
Source:
Journal of chromatography 2020 v.1143 pp. 121972
ISSN:
1570-0232
Subject:
acetic acid; acidification; chemical species; derivatization; ethyl ether; feces; fermentation; flame ionization; hexanoic acid; humans; intestinal microorganisms; metabolites; mice; polyethylene glycol; propionic acid; quantitative analysis; rats
Abstract:
... Short-chain fatty acids (SCFAs) are gut microbiota metabolites recognized for their beneficial effects on the host organism. In this study, a simple and rapid sample preparation method combined to SCFAs analysis by direct injection and gas chromatography coupled with flame ionization detection (GC-FID), for the determination and quantification of eight SCFAs (acetic, propionic, i-butyric, butyric, ...
DOI:
10.1016/j.jchromb.2020.121972

11. Fast determination of four polar contaminants in soy nutraceutical products by liquid chromatography coupled to tandem mass spectrometry

Author:
Renata Domingos Alves; Roberto Romero-González; Rosalía López-Ruiz; M. L. Jiménez-Medina; Antonia Garrido Frenich
Source:
Analytical and bioanalytical chemistry 2016 v.408 no.28 pp. 8089-8098
ISSN:
1618-2642
Subject:
acetonitrile; acidification; adsorbents; carbon; derivatization; formic acid; functional foods; liquid chromatography; maleic hydrazide; methanol; perchlorates; polar compounds; solvents; tandem mass spectrometry
Abstract:
... An analytical method based on a modified QuPPe (quick polar pesticide) extraction procedure coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was evaluated for the determination of four polar compounds (chlorate, fosetyl-Al, maleic hydrazide, and perchlorate) in nutraceutical products obtained from soy. Experimental conditions including extraction such as solvent, acidificatio ...
DOI:
10.1007/s00216-016-9912-2

12. High-performance liquid chromatography determination of glyoxal, methylglyoxal, and diacetyl in urine using 4-methoxy-o-phenylenediamine as derivatizing reagent

Author:
Armando Gómez Ojeda; Katarzyna Wrobel; Alma Rosa Corrales Escobosa; Ma. Eugenia Garay-Sevilla; Kazimierz Wrobel
Source:
Analytical biochemistry 2014 v.449 pp. 52-58
ISSN:
0003-2697
Subject:
acetonitrile; acidification; alcoholic beverages; biomarkers; calibration; derivatization; diacetyl; fluorometry; glycation; juveniles; oxidative stress; pH; patients; quinoxalines; reversed-phase high performance liquid chromatography; separation; urine
Abstract:
... Bioanalytical relevance of glyoxal (Go) and methylglyoxal (MGo) arises from their role as biomarkers of glycation processes and oxidative stress. The third compound of interest in this work is diacetyl (DMGo), a component of different food products and alcoholic beverages and one of the small α-ketoaldehydes previously reported in urine. The original idea for the determination of the above compoun ...
DOI:
10.1016/j.ab.2013.12.014

13. Ion chromatography combined with online electrochemical derivatization and fluorescence detection for the determination of carbamazepine in human plasma

Author:
Shuchao Wu; Wei Xu; Qamar Subhani; Bingcheng Yang; Deying Chen; Yan Zhu; Lanjuan Li
Source:
Talanta 2012 v.101 no. pp. 541-545
ISSN:
0039-9140
Subject:
acetonitrile; acidification; anion exchange; derivatization; detection limit; electrochemistry; fluorescence; humans; ion exchange chromatography; phosphoric acid; sodium hydroxide
Abstract:
... This paper describes the determination of carbamazepine (CBZ) in human plasma using ion chromatography combined with online electrochemical derivatization and fluorescence detection. Separation of CBZ with anion exchange column was demonstrated to be feasible using either basic (10mM NaOH) or acidic (0.1 M H₃PO₄) reagent with a small amount of acetonitrile (ACN) added as eluent. Electrochemical de ...
DOI:
10.1016/j.talanta.2012.09.039

14. Multifunctional properties and safety evaluation of lactic acid bacteria and yeasts associated with fermented cereal doughs

Author:
Marcel Houngbédji; S. Wilfrid Padonou; Charles Parkouda; Pernille Greve Johansen; Mathias Hounsou; B. Pélagie Agbobatinkpo; Hagretou Sawadogo-Lingani; Lene Jespersen; D. Joseph Hounhouigan
Source:
World journal of microbiology & biotechnology 2021 v.37 no.2 pp. 34
ISSN:
0959-3993
Subject:
Candida glabrata; Pichia kudriavzevii; Saccharomyces cerevisiae; Weissella confusa; acidification; amphotericin B; ampicillin; antibiotic resistance; antifungal properties; biotechnology; chloramphenicol; derivatization; dough; erythromycin; fermentation; fluconazole; free amino acids; itraconazole; kanamycin; lactic acid; liquids; minimum inhibitory concentration; phenotype; reversed-phase high performance liquid chromatography; streptomycin; tetracycline; yeasts; Benin
Abstract:
... Spontaneous cereal fermentations involve diverse lactic acid bacteria (LAB) and yeasts which may include multifunctional and safe or unsafe strains. This study assessed acidification ability, safety, antifungal activity and free amino acids release ability of LAB and yeasts previously isolated from spontaneously fermented cereal doughs in Benin. Fourteen LAB and thirteen yeast strains were studied ...
DOI:
10.1007/s11274-021-02994-8

15. Optimization and validation of direct gas chromatography-mass spectrometry method for simultaneous quantification of ten short-chain fatty acids in rat feces

Author:
Jin-Hao Zhu; Qian Mao; Si-Yu Wang; Hui Liu; Shan-Shan Zhou; Wei Zhang; Ming Kong; He Zhu; Song-Lin Li
Source:
Journal of chromatography 2022 v.1669 pp. 462958
ISSN:
0021-9673
Subject:
acidification; derivatization; ethyl ether; feces; formic acid; gas chromatography-mass spectrometry; rats; temperature; toxicity
Abstract:
... Short-chain fatty acids (SCFAs) play key roles in maintaining health and treating disease. Quantification of important fecal SCFAs is necessary to facilitate the clarification of their biological roles. However, the existing quantifying methods mainly depend on complicated precolumn derivatization, and/or are unable to determine formic acid, a SCFA commonly associated with toxicity. In this study, ...
DOI:
10.1016/j.chroma.2022.462958

16. Profiling thiol metabolites and quantification of cellular glutathione using FT-ICR-MS spectrometry

Author:
Sadakatali S. Gori; Pawel Lorkiewicz; Daniel S. Ehringer; Alex C. Belshoff; Richard M. Higashi; Teresa W.-M. Fan; Michael H. Nantz
Source:
Analytical and bioanalytical chemistry 2014 v.406 no.18 pp. 4371-4379
ISSN:
1618-2642
Subject:
acidification; adenocarcinoma; cysteine; derivatization; glutathione; homocysteine; humans; isotopes; metabolites; pH; spectroscopy; thiols
Abstract:
... We describe preparation and use of the quaternary ammonium-based α-iodoacetamide QDE and its isotopologue *QDE as reagents for chemoselective derivatization of cellular thiols. Direct addition of the reagents to live cells followed by adduct extraction into n-butanol and analysis by FT-ICR-MS provided a registry of matched isotope peaks from which molecular formulae of thiol metabolites were deriv ...
DOI:
10.1007/s00216-014-7810-z
PubMed:
24858467
PubMed Central:
PMC4144182

17. Rapid analysis of quinones in complex matrices by derivatization-based wooden-tip electrospray ionization mass spectrometry

Author:
Chen Ling; Qiaofang Shi; Zhanpeng Wei; Jingjing Zhang; Junjie Hu; Jiying Pei
Source:
Talanta 2022 v.237 pp. 122912
ISSN:
0039-9140
Subject:
acidification; blood serum; cysteamine; derivatization; electric potential difference; electrospray ionization mass spectrometry; human health; ionization; rapid methods; solvents; urine
Abstract:
... Quinones are important components participating in various biological processes as well as hazardous substances to human health. Rapid determination of quinones in environmental samples and biofluids is the basis for assessing their health effect. Here, we presented a rapid, straightforward, highly sensitive and environmental-friendly wooden-tip electrospray ionization mass spectrometry (ESI-MS) m ...
DOI:
10.1016/j.talanta.2021.122912

18. Sensitive analysis of amino acids with carrier-mediated single drop microextraction in-line coupled with capillary electrophoresis

Author:
Jeongmi Choi; Kihwan Choi; Jihye Kim; Ahmed Yacine Badjah Hadj Ahmed; Zeid A. Al-Othman; Doo Soo Chung
Source:
Journal of chromatography 2011 v.1218 no.41 pp. 7227-7233
ISSN:
0021-9673
Subject:
acidification; agitation; amino acids; capillary electrophoresis; centrifugation; chromatography; correlation; derivatization; humans; microextraction; urine
Abstract:
... In order to analyze amino acids sensitively without derivatization, we have developed carrier-mediated single drop microextraction (SDME). Nonane-1-sulfonic acid was added to an acidic sample donor solution as a carrier to form neutral ion pair complexes with amino acids. The ion pair complexes were extracted to the organic phase, covering a drop of an aqueous basic acceptor phase hanging at the t ...
DOI:
10.1016/j.chroma.2011.08.035

19. Sensitivity improvement of the LC–MS/MS quantification of carbidopa in human plasma and urine by derivatization with 2,4-pentanedione

Author:
Nico C. van de Merbel; Kees J. Bronsema; Steven H. Gorman; Ray Bakhtiar
Source:
Journal of chromatography 2017 v.1064 pp. 62-67
ISSN:
1570-0232
Subject:
acidification; antioxidants; butylated hydroxytoluene; derivatization; excretion; guidelines; humans; hydrazine; ice; ionization; pH; pharmacokinetics; reversed-phase liquid chromatography; sodium metabisulfite; stable isotopes; tandem mass spectrometry; urine
Abstract:
... The reliable quantification of carbidopa in biological samples at low concentrations is challenging because of the polar and highly unstable nature of the compound. In this paper, LC–MS/MS methods are described for the determination of carbidopa in 50μL of human plasma and 25μL of human urine in the concentration ranges 1–1,000ng/mL and 100–50,000ng/mL, respectively. After a simple protein precipi ...
DOI:
10.1016/j.jchromb.2017.09.010

20. Simultaneous Analysis of Zofenopril and Its Active Metabolite Zofenoprilat in Human Plasma by LC-ESI-MS Using Pre-Column Derivatization with p-Bromophenacyl Bromide

Author:
Gao, Fang; Ding, Li; Ma, Pengcheng; Wu, Fei
Source:
Chromatographia 2010 v.71 no.11-12 pp. 1007-1014
ISSN:
0009-5893
Subject:
acetic acid; acidification; ammonium acetate; bioavailability; calcium; derivatization; electrospray ionization mass spectrometry; humans; liquid chromatography; metabolites; thiols; volunteers
Abstract:
... Zofenoprilat is an active metabolite of zofenopril, which is very unstable in plasma because of oxidative degradation of its thiol group. In this method, p-bromophenacyl bromide was used as derivatization reagent, immediately after plasma separation, to react with the free thiol group of zofenoprilat and form the derivative zofenoprilat-p-BPB. After acidification with 50% acetic acid, the derivati ...
DOI:
10.1365/s10337-010-1606-x

21. Simultaneous analysis of non-steroidal anti-inflammatory drugs and estrogenic hormones in water and wastewater samples using gas chromatography–mass spectrometry and gas chromatography with electron capture detection

Author:
Natalia Migowska; Magda Caban; Piotr Stepnowski; Jolanta Kumirska
Source:
Science of the total environment 2012 v.441 no. pp. 77-88
ISSN:
0048-9697
Subject:
acidification; derivatization; effluents; electrons; endocrine-disrupting chemicals; gas chromatography; hormones; households; irradiation; methanol; microwave ovens; nonsteroidal anti-inflammatory agents; river water; solid phase extraction; surface water; temperature; wastewater; Poland
Abstract:
... Non-steroidal anti-inflammatory drugs are the group of pharmaceuticals that is most often found in the environment, whereas estrogenic hormones are considered to be potent endocrine disruptors. However, the fate and persistence of these compounds in the environment are still unclear. In this study we propose two approaches for determining these compounds in environmental water samples: GC–MS using ...
DOI:
10.1016/j.scitotenv.2012.09.043
PubMed:
23137972

22. The development of a gas chromatographic-mass spectrometric analytical procedure for the determination of lipids, proteins and resins in the same paint micro-sample avoiding interferences from inorganic media

Author:
Bonaduce, Ilaria; Cito, Marcello; Colombini, Maria Perla
Source:
Journal of chromatography 2009 v.1216 no.32 pp. 5931-5939
ISSN:
0021-9673
Subject:
acidification; amino acids; animals; anions; casein; cations; derivatization; dryers; eggs; gas chromatography; hydrolysis; lipids; mass spectrometry; metals; pigments; resins; saponification; terpenoids; waxes
Abstract:
... This paper presents a GC-MS analytical procedure for determining proteinaceous materials, glycerolipids, natural waxes and terpenoid resins in the same paint micro-sample. The procedure is also reliable when high amounts of interfering inorganic pigments, dryers and charges are present. The characterisation of proteinaceous binders in a paint sample can be subject to analytical interferences by in ...
DOI:
10.1016/j.chroma.2009.06.033

23. Ultratrace-level determination of glyphosate, aminomethylphosphonic acid and glufosinate in natural waters by solid-phase extraction followed by liquid chromatography–tandem mass spectrometry: performance tuning of derivatization, enrichment and detection

Author:
Irene Hanke; Heinz Singer; Juliane Hollender
Source:
Analytical and bioanalytical chemistry 2008 v.391 no.6 pp. 2265-2276
ISSN:
1618-2642
Subject:
EDTA (chelating agent); acetonitrile; acidification; byproducts; derivatization; detection limit; glufosinate; glyphosate; groundwater; liquid chromatography; metal ions; methylene chloride; solid phase extraction; solvents; spectrometers; surface water; tandem mass spectrometry
Abstract:
... A sensitive and robust analytical method for the quantification of glyphosate, aminomethylphosphonic acid (AMPA) and glufosinate in natural water has been developed on the basis of a derivatization with 9-fluorenylmethylchloroformate (FMOC-Cl), solid-phase extraction (SPE) and liquid chromatography followed by electrospray tandem mass spectrometry (LC-ESI-MS/MS). In order to maximize sensitivity, ...
DOI:
10.1007/s00216-008-2134-5
PubMed:
18481049