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You searched for: Subject term chemical species Remove constraint Subject term: chemical species Subject term acetic acid Remove constraint Subject term: acetic acid
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1. A Combination of Chromatography with Tandem Mass Spectrometry Systems (UPLC-MS/MS and GC-MS/MS), Modified QuEChERS Extraction and Mixed-Mode SPE Clean-Up Method for the Analysis of 656 Pesticide Residues in Rice

Author:
Thanh-Thien Tran-Lam; Minh Quang Bui; Hoa Quynh Nguyen; Yen Hai Dao; Giang Truong Le
Source:
Foods 2021 v.10 no.10 pp. -
ISSN:
2304-8158
Subject:
acetic acid; adsorption; chemical species; compliance; insecticides; protocols; rice; solvents; tandem mass spectrometry; Vietnam
Abstract:
... The emerging ungovernable application of pesticides in rice farming has attracted public concerns as these hazardous chemicals leave long-lasting environmental impacts and cause severe health effects. Here, an optimized analytical method was proposed for the measurement of 656 pesticide residues in rice samples collected in Vietnam. We utilized chromatography with tandem mass spectrometry systems ...
DOI:
10.3390/foods10102455

2. A Sol–gel Method for Preparing Poly (N-Isopropyl Acrylamide) Hybrid Column and Its Application in Small Molecular Analysis Using Capillary Liquid Chromatography

Author:
Yang Zhao; Jiao Zeng; Junheng You; Yuanxing Duan; Yuandong Li; Chunbo Liu; Zhihua Liu; Liu Yang; Qinpeng Shen; Zhenjie Li
Source:
Chromatographia 2020 v.83 no.8 pp. 985-992
ISSN:
0009-5893
Subject:
acetic acid; acrylamides; chemical species; chlorophenols; free radicals; hydrolysis; permeability; polyethylene glycol; polymerization; reversed-phase liquid chromatography; sol-gel processing; temperature; urea
Abstract:
... A poly (N-isopropyl acrylamide) (polyNIPA)-based hybrid column for capillary liquid chromatography (cLC) was prepared with N-isopropyl acrylamide (NIPA) and alkoxysilanes through a sol–gel “one-pot” method. In this process, the hydrolyzed tetramethoxysilane (TMOS) and vinyltrimethoxysilane (VTMS) were the precursors for the synthesis of a silica-based monolith and subsequently reacted with organic ...
DOI:
10.1007/s10337-020-03906-y

3. A detection and confirmation strategy for screening of veterinary drugs in honey by liquid chromatography coupled quadrupole time-of-flight mass spectrometry

Author:
Zhibin Wang; Yan Li; Qiaoying Chang; Jian Kang; Guo-Fang Pang
Source:
Analytical methods 2017 v.10 no.1 pp. 59-68
ISSN:
1759-9679
Subject:
acetic acid; acetonitrile; chemical species; ciprofloxacin; cleaning; data collection; databases; honey; liquid chromatography; macrolides; mass spectrometry; pH; screening; sorbents; sulfonamides; tetracyclines; veterinary drugs
Abstract:
... A strategy for the quantification and confirmation of 40 multi-class veterinary drugs in honey by QuEChERS (quick, easy, cheap, effective, rugged, and safe) combined with liquid chromatography coupled quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS) is described. The veterinary drugs examined belong to four classes: quinolones, sulfonamides, macrolides, and tetracyclines. Before analysis ...
DOI:
10.1039/c7ay02440a

4. A new anion exchange purification method for Cu stable isotopes in blood samples

Author:
Shun-Chung Yang; Lisa Welter; Anand Kolatkar; Jorge Nieva; Kathryn R. Waitman; Kuo-Fang Huang; Wen-Hsuan Liao; Shotaro Takano; William M. Berelson; A. Joshua West; Peter Kuhn; Seth G. John
Source:
Analytical and bioanalytical chemistry 2019 v.411 no.3 pp. 765-776
ISSN:
1618-2642
Subject:
acetic acid; anion exchange; biopsy; blood sampling; blood serum; cadmium; chemical species; copper; homeostasis; humans; hydrochloric acid; iron; isotope fractionation; liquids; metabolism; neoplasms; patients; purification methods; rapid methods; stable isotopes; zinc
Abstract:
... The isotopic composition of iron, zinc, copper, and cadmium (δ⁵⁶Fe, δ⁶⁶Zn, δ⁶⁵Cu, and δ¹¹⁴Cd) are novel and promising tools to study the metabolism and homeostasis of trace metals in the human body. Serum δ⁶⁵Cu has been proposed as a potential tool for diagnosis of cancer in liquid biopsy, and other metals may have similar utility. However, accurate analysis of trace metal isotopes is challenging ...
DOI:
10.1007/s00216-018-1498-4

5. A new clean-up approach for stomach content toxicological analysis

Author:
Mariana D. Peres; Simone Nascimento; Fabrício S. Pelição
Source:
Forensic science international 2019 v.302 pp. 109936
ISSN:
0379-0738
Subject:
acetic acid; acetonitrile; biotransformation; carbaryl; carbofuran; centrifugation; chemical species; cocaine; detection limit; diazepam; diazinon; forensic sciences; gas chromatography-mass spectrometry; heptachlor; lipids; magnesium sulfate; malathion; permethrin; phenobarbital; poisoning; prochloraz; sodium chloride; sorbents; stomach; toxicity testing
Abstract:
... Stomach content is a matrix often applied in post-mortem cases. It is especially important in oral intoxication cases. The main advantages are the usually high concentration of analytes and the lack of biotransformation process. Still, even with extensive sample preparation, the final extract is not always suitable for analysis. The aim of this study was to develop an alternative method using QuEC ...
DOI:
10.1016/j.forsciint.2019.109936

6. A rapid and robust method for amino acid quantification using a simple N-hydroxysuccinimide ester derivatization and liquid chromatography-ion mobility-mass spectrometry

Author:
Taylor M. Domenick; Austin L. Jones; Robin H. J. Kemperman; Richard A. Yost
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.18 pp. 5549-5559
ISSN:
1618-2642
Subject:
acetic acid; amino acids; analytical chemistry; chemical species; derivatization; mass spectrometry; metabolites; metabolomics; neuroglia; reversed-phase liquid chromatography; yeast extract
Abstract:
... The vast majority of mass spectrometry (MS)-based metabolomics studies employ reversed-phase liquid chromatography (RPLC) to separate analytes prior to MS detection. Highly polar metabolites, such as amino acids (AAs), are poorly retained by RPLC, making quantitation of these key species challenging across the broad concentration ranges typically observed in biological specimens, such as cell extr ...
DOI:
10.1007/s00216-022-03993-w

7. A strategy of utilizing Cu2+-mediating interaction to prepare magnetic imprinted polymers for the selective detection of celastrol in traditional Chinese medicines

Author:
Fei Li; Xiaoxuan Li; Jie Su; Yijun Li; Xiwen He; Langxing Chen; Yukui Zhang
Source:
Talanta 2021 v.231 pp. 122339
ISSN:
0039-9140
Subject:
acetic acid; adsorbents; adsorption; carbon nanotubes; catalysts; chemical species; detection limit; magnetism; methanol; molecular imprinting; polymerization
Abstract:
... In this work, a novel strategy to prepare molecularly imprinted polymers (MIPs) functionalized magnetic carbon nanotubes (MCNTs) via a facile sol-gel polymerization by adopting Cu²⁺-mediating interaction was presented for selective recognition of celastrol (Cel), in the traditional Chinese medicines (TCM). Firstly, template Cel, 3-aminopropyltriethoxysilane (APTES) as monomer and Cu²⁺ (co-monomer) ...
DOI:
10.1016/j.talanta.2021.122339

8. Acetic acid-modified zinc oxide nanoparticles for solid phase extraction of Cu(II) and Cr(III) in water

Author:
Asnake Tesfaye; Meseret Amde; Endale Teju; Deribachew Bekana; Negussie Megersa
Source:
Toxicological and environmental chemistry 2022 v.104 no.1 pp. 20-35
ISSN:
1029-0486
Subject:
acetic acid; adsorbents; atomic absorption spectrometry; chemical species; ionic strength; pH; solid phase extraction; toxicity; toxicology; water pollution; zinc oxide
Abstract:
... Water pollution due to toxic metals may pose a significant effect on the environment and the biota indicating the necessity of careful management of their concentration in the system. On the other hand, a simplified and useable sample preparation technique is required for their trace analysis. In this report, a simple solid-phase extraction procedure was developed for fast extraction and preconcen ...
DOI:
10.1080/02772248.2021.2007922

9. An antibody-free LC-MS/MS method for the quantification of intact insulin-like growth factors 1 and 2 in human plasma [Erratum: August 2021, Vol.413(21), p.5529]

Author:
Mark S. Pratt; Martijn van Faassen; Noah Remmelts; Rainer Bischoff; Ido P. Kema
Source:
Analytical and bioanalytical chemistry 2021 v.413 no.8 pp. 2035-2044
ISSN:
1618-2642
Subject:
acetic acid; acetone; acetonitrile; analytical chemistry; biomarkers; chemical species; dissociation; electrospray ionization mass spectrometry; ethanol; humans; immunoassays; quantitative analysis; reference standards; spectrometers
Abstract:
... Insulin-like growth factors 1 and 2 (IGF-1 and IGF-2) are important biomarkers in research and diagnosis of growth disorders. Quantitative analysis is performed using various ligand-binding assays or enzymatic digestion LC-MS/MS methods, whose widespread adoption is hampered by time-consuming sample preparation procedures. We present a simple and fast antibody-free LC-MS/MS method for the quantifi ...
DOI:
10.1007/s00216-021-03185-y

10. An untargeted evaluation of the volatile and semi-volatile compounds migrating into food simulants from polypropylene food containers by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry

Author:
C. Carrero-Carralero; J. Escobar-Arnanz; M. Ros; S. Jiménez-Falcao; M.L. Sanz; L. Ramos
Source:
Talanta 2019 v.195 pp. 800-806
ISSN:
0039-9140
Subject:
acetic acid; chemical species; comprehensive two-dimensional gas chromatography; containers; databases; ethanol; iso-octanes; manufacturing; mass spectrometry; polypropylenes; volatile compounds
Abstract:
... This study reports on the potential of comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GC×GC−ToF MS) for the exhaustive untargeted characterization of the volatile and semi-volatile analytes migrating from four commercial polypropylene food containers into four simulants (water, 3% acetic acid, 10% ethanol, and isooctane) according to European Regul ...
DOI:
10.1016/j.talanta.2018.12.011

11. Analysis of β-agonists in different biological matrices by liquid chromatography–tandem mass spectrometry

Author:
Tomasz Śniegocki; Bartosz Sell; Andrzej Posyniak
Source:
Journal of Veterinary Research 2021 v.65 no.4 pp. 469-475
ISSN:
2450-8608
Subject:
acetic acid; adverse effects; ammonium acetate; bronchodilators; chemical species; clenbuterol; enzymatic hydrolysis; isoxsuprine; liver; lungs; methanol; muscle tissues; muscles; oxygen; pH; protein synthesis; ractopamine; solid phase extraction; tandem mass spectrometry; therapeutics; urine; veterinary medicine; zilpaterol hydrochloride
Abstract:
... Wide use is made of β-agonists in therapy due to their smooth muscle–relaxant properties. They also have a side effect of increasing muscle mass. Besides improving oxygen utilisation as bronchodilators, β-agonists increase protein synthesis and promote fat burning. The growth- and performance-enhancing effects are often exploited in illegal use. The guiding objective of this study was to develop a ...
DOI:
10.2478/jvetres-2021-0058

12. Application of a fabric phase sorptive extraction-high performance liquid chromatography-photodiode array detection method for the trace determination of methyl paraben, propyl paraben and butyl paraben in cosmetic and environmental samples

Author:
Sumeyra Gülle; Halil Ibrahim Ulusoy; Abuzar Kabir; Angela Tartaglia; Kenneth G. Furton; Marcello Locatelli; Victoria F. Samanidou
Source:
Analytical methods 2019 v.11 no.48 pp. 6136-6145
ISSN:
1759-9679
Subject:
acetic acid; acetonitrile; adsorption; chemical species; desorption; detection limit; fabrics; filtration; high performance liquid chromatography; methanol; models; pH; solvents; standard deviation
Abstract:
... A new sample preparation and chromatographic separation method for methyl paraben (MP), propyl paraben (PP) and butyl paraben (BP) in cosmetic and environmental samples has been developed, based on fabric phase sorptive extraction (FPSE) and high performance liquid chromatography-photodiode array (HPLC-PDA) detection. In the proposed method, MP, PP and BP molecules were efficiently retained on a s ...
DOI:
10.1039/c9ay02260k

13. Chemical fingerprint and simultaneous determination of flavonoids in Flos Sophorae Immaturus by HPLC-DAD and HPLC-DAD-ESI-MS/MS combined with chemometrics analysis

Author:
Zhisheng Xie; Shingchung Lam; Junwei Wu; Depo Yang; Xinjun Xu
Source:
Analytical methods 2014 v.6 no.12 pp. 4328-4335
ISSN:
1759-9679
Subject:
acetic acid; acetonitrile; chemical species; chemometrics; cluster analysis; high performance liquid chromatography; principal component analysis; quality control; quantitative analysis; quercetin; regression analysis; rutin; wavelengths; China
Abstract:
... A simple and efficient HPLC method is developed for the fingerprint analysis of Flos Sophorae Immaturus and for the simultaneous determination of three flavonoids in Flos Sophorae Immaturus, namely rutin, narcissin and quercetin. The separation of analytes is conducted on a Dikma Diamonsil C₁₈ column (250 mm × 4.6 mm, 5 μm) at 35 °C; the wavelength of UV detector was set at 254 nm; the mobile phas ...
DOI:
10.1039/c4ay00289j

14. Comparative Pharmacokinetic Study of Three Major Bioactive Components in the Normal and Different Courses of Liver-Stagnation and Spleen-Deficiency Syndrome Depressive Rats after Intragastric Administration of Zhi-Zi-Hou-Po Decoction

Author:
Kaiwen Luo; Mengdie Wang; Xiangxiang Pan; Yadong Xing
Source:
Journal of Analytical Methods in Chemistry (Online) 2022 v.2022 pp. -
ISSN:
2090-8873
Subject:
acetic acid; acetonitrile; antidepressants; chemical species; computer software; digestive tract; honokiol; intragastric administration; liver; models; naringin; oral administration; pharmacokinetics; rats; serotonin; sucrose; tandem mass spectrometry; ultra-performance liquid chromatography
Abstract:
... To reveal the pharmacokinetic process of narirutin, naringin, and honokiol in normal and different courses of liver-stagnation and spleen-deficiency syndrome depressive rats after intragastric administration of Zhi-Zi-Hou-Po decoction (ZZHPD), a rapid ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) method was proposed in this study. Chronic unpredicta ...
DOI:
10.1155/2022/8657616

15. Comprehensive and quantitative profiling of B vitamins and related compounds in the mammalian liver

Author:
Juan Xu; Constance E. Clare; Amey H. Brassington; Kevin D. Sinclair; David A. Barrett
Source:
Journal of chromatography 2020 v.1136 pp. 121884
ISSN:
1570-0232
Subject:
acetic acid; acetonitrile; acid hydrolysis; amines; chemical species; cold; detection limit; diet; electrospray ionization mass spectrometry; epigenetics; flavin-adenine dinucleotide; genetic variation; hydrophilic interaction chromatography; ionization; isotope labeling; liver; metabolism; models; pyridoxal; pyridoxal phosphate; quantitative analysis; sarcosines; sheep; thiamin; vitamin status
Abstract:
... A method for the simultaneous quantification of B vitamins and related amines in one-carbon (1C) metabolism would benefit the study of diet and genetic/epigenetic regulation of mammalian development and health. We present a validated method for the simultaneous quantitative analysis of 13 B vitamers and four related 1C-pathway amine intermediates in liver using hydrophilic interaction chromatograp ...
DOI:
10.1016/j.jchromb.2019.121884
PubMed:
31821966
PubMed Central:
PMC6961113

16. Determination and pharmacokinetics study of oxyclozanide suspension in cattle by LC-MS/MS

Author:
Jili Zhang; Yubin Bai; Bing Li; Xuzheng Zhou; Hongfei Si; Jiyu Zhang
Source:
BMC veterinary research 2019 v.15 no.1 pp. 210
ISSN:
1746-6148
Subject:
high performance liquid chromatography; oral administration; drugs; chemical species; oxyclozanide; standard deviation; half life; formates; monitoring; chlorine; cattle; models; acetonitrile; niclosamide; ammonium; pharmacokinetics; acetic acid; fascioliasis; methanol; tandem mass spectrometry; fluorine
Abstract:
... BACKGROUND: Oxyclozanide is an anthelmintic drug that is widely used to treat fasciolosis. However, the pharmacokinetics of oxyclozanide in cattle are not yet clearly understood. The present study was designed to develop a sensitive method to determine oxyclozanide levels in cattle plasma using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and to study its pharmacoki ...
DOI:
10.1186/s12917-019-1963-0
PubMed:
31234851
PubMed Central:
PMC6591842

17. Determination of S-adenosylmethionine and S-adenosylhomocysteine in blood plasma by UPLC with fluorescence detection

Author:
Alexander Vladimirovich Ivanov; Ekaterina Alexandrovna Dubchenko; Maria Petrovna Kruglova; Edward Danielevich Virus; Polina Olegovna Bulgakova; Valery Vasil'evich Alexandrin; Anatolij Nikolaevich Fedoseev; Alexey Nikolaevich Boyko; Sergej Vitalievich Grachev; Aslan Amirkhanovich Kubatiev
Source:
Journal of chromatography 2019 v.1124 pp. 366-374
ISSN:
1570-0232
Subject:
S-adenosylmethionine; acetic acid; acetonitrile; blood plasma; chemical species; derivatization; detection limit; fluorescence; metabolites; phenylboronic acids; potassium dihydrogen phosphate; solid phase extraction; ultra-performance liquid chromatography; volunteers
Abstract:
... A validated approach to determine various methionine cycle metabolites (S-adenosylmethionine, S-adenosylhomocysteine, and methylthioadenosine) in human blood plasma is offered. The approach is based on solid-phase extraction (with grafted phenylboronic acid) and derivatization with chloroacetaldehyde followed by ultra-performance liquid chromatography with fluorescence detection. We used a 100 × 2 ...
DOI:
10.1016/j.jchromb.2019.06.032

18. Determination of phenolic compounds in extracts of Amazonian medicinal plants by liquid chromatography-electrospray tandem mass spectrometry

Author:
Henrique Faccin; Roberta Fabricio Loose; Carine Viana; Osmar A. Lameira; Leandro Machado de Carvalho
Source:
Analytical methods 2017 v.9 no.7 pp. 1141-1151
ISSN:
1759-9679
Subject:
Bauhinia variegata; Cecropia palmata; Connarus; Mansoa alliacea; acetic acid; acetonitrile; apigenin; caffeic acid; catechin; chemical species; chlorogenic acid; data collection; detection limit; ferulic acid; high performance liquid chromatography; medicinal plants; monitoring; p-coumaric acid; rutin; tandem mass spectrometry; ultra-performance liquid chromatography; vanillic acid; Amazonia; Brazil
Abstract:
... A method for the separation, identification and quantification of 24 phenolic compounds using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed and validated. Six species of traditional medicinal plants from the Brazilian Amazon region were studied (Mansoa alliacea, Bauhinia variegata var. variegata, Bauhinia variegata var. alboflava, Conn ...
DOI:
10.1039/c6ay02937j

19. Determination of selected emerging contaminants in freshwater invertebrates using a universal extraction technique and liquid chromatography accurate mass spectrometry

Author:
Jalal T. Althakafy; Chadin Kulsing; Michael R. Grace; Philip J. Marriott
Source:
Journal of separation science 2018 v.41 no.19 pp. 3706-3715
ISSN:
1615-9306
Subject:
acetic acid; acetonitrile; aquatic invertebrates; calibration; chemical species; computer software; drugs; energy; freshwater; ions; liquid chromatography; liquid-liquid extraction; personal care products; streams; tandem mass spectrometry
Abstract:
... A simple sample preparation method based on a modified liquid‐phase extraction approach to extract selected pharmaceuticals and personal care products from freshwater organisms is described. Extracted samples were analysed using liquid chromatography with Q‐Exactive plus hybrid quadrupole Orbitrap mass spectrometry, using 2.6 μm C18 media. A 0.1% v/v acetic acid/acetonitrile mobile phase was appli ...
DOI:
10.1002/jssc.201800507

20. Determination of sildenafil and vardenafil by capillary zone electrophoresis using capacitively coupled contactless conductivity detection

Author:
Denis Tadeu Rajh Vidal; Marcio Antonio Augelli; Claudimir Lucio do Lago
Source:
Analytical methods 2013 v.5 no.8 pp. 2041-2045
ISSN:
1759-9679
Subject:
acetic acid; aqueous solutions; capillary zone electrophoresis; chemical species; detectors; electrolytes; enzymes; high performance liquid chromatography
Abstract:
... A method based on capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C⁴D) for determination of two important phosphodiesterase type-5 inhibitors (sildenafil and vardenafil) is introduced. The background electrolyte (BGE) consisted of an aqueous solution of 500 mmol L⁻¹ acetic acid, and the capillary was previously treated with polybrene solution to prevent c ...
DOI:
10.1039/c3ay26470j

21. Determination of sixteen pyrethroids in water using dispersive liquid–liquid microextraction based on dissolved carbon dioxide flotation after emulsification microextraction using gas chromatography with triple quadrupole mass spectrometry

Author:
Jingqing Ye; Zhoulin Yao; Zhiwei Wang; Jing Nie; Zuguang Li
Source:
Analytical methods 2016 v.8 no.32 pp. 6194-6201
ISSN:
1759-9679
Subject:
acetic acid; acetonitrile; centrifugation; chemical species; dissolved carbon dioxide; emulsifying; gas chromatography; glass; liquid-phase microextraction; mass spectrometry; pyrethrins; separation; sodium bicarbonate; solvents
Abstract:
... A method using dissolved carbon dioxide flotation after dispersive liquid–liquid microextraction (DCF-DLLME) was proposed for the determination of sixteen pyrethroids in water samples, coupled with gas chromatography with triple quadrupole mass spectrometry in a homemade glass round flask. The DCF-DLLME method is based on the rapid and simple phase separation of a low density organic solvent from ...
DOI:
10.1039/c6ay01503d

22. Determination of sulfonylurea pesticide residues in edible seeds used as nutraceuticals by QuEChERS in combination with ultra-high-performance liquid chromatography-tandem mass spectrometry

Author:
Maykel Hernández-Mesa; Ana M. García-Campaña
Source:
Journal of chromatography 2020 v.1617 pp. 460831
ISSN:
0021-9673
Subject:
Helianthus annuus; Salvia hispanica; acetic acid; acetonitrile; chemical species; commercialization; detection limit; dietary supplements; guidelines; laws and regulations; liquid chromatography; maximum residue limits; methanol; pesticide residues; pumpkins; seeds; standard deviation; sulfonylureas; tandem mass spectrometry; temperature
Abstract:
... This work proposes a novel Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method in combination with ultra-high performance liquid chromatography-tandem mass spectrometry for the determination of sulfonylurea residues in edible seeds. The chromatographic separation of nine sulfonylureas was accomplished in less than 5.5 min, using a Luna Omega C₁₈ column (50 × 2.1 mm, 1.6 µm). Mobile p ...
DOI:
10.1016/j.chroma.2019.460831

23. 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

24. Development of a Validated UHPLC-ESI (-)-HRMS Methodology for the Simultaneous Quantitative Determination of Hesperidin, Hesperetin, Naringin, and Naringenin in Chicken Plasma

Author:
Eirini Baira; Ioanna Dagla; Eleni Siapi; Panagiotis Zoumpoulakis; Anthony Tsarbopoulos; Panagiotis Simitzis; Michael Goliomytis; Stelios G Deligeorgis; Alexios-Leandros Skaltsounis; Evagelos Gikas
Source:
Food analytical methods 2019 v.12 no.5 pp. 1187-1196
ISSN:
1936-9751
Subject:
acetic acid; acetone; acetonitrile; broiler chickens; chemical species; cold; dietary supplements; hesperetin; hesperidin; ionization; isopropyl alcohol; naringenin; naringin; quantitative analysis; ultra-performance liquid chromatography
Abstract:
... A highly sensitive and specific methodology has been developed for the simultaneous determination of the flavonoids hesperidin, hesperetin, naringin, and naringenin in chicken plasma employing UHPLC-HRMS (Orbitrap Velos). Plasma samples were preprocessed by protein precipitation with cold acetone. Analysis was carried out on an INTERCHIM UHPLC C18 column using aq. 0.1% glacial acetic acid, acetoni ...
DOI:
10.1007/s12161-018-01420-4

25. Direct detection of inorganic ions and underivatized amino acids in seconds using high-speed capillary electrophoresis coupled with back-scatter interferometry

Author:
Miyuru De Silva; Prabhavie M. Opallage; Robert C. Dunn
Source:
Analytical methods 2021 v.13 no.11 pp. 1340-1348
ISSN:
1759-9679
Subject:
acetic acid; arginine; capillary electrophoresis; chemical species; diagnostic techniques; interferometry; metabolic diseases; pH; refractive index
Abstract:
... High speed capillary electrophoresis (HSCE) combined with refractive index (RI) detection is developed for the rapid separation and detection of inorganic ions and amino acids. A mixture of three inorganic ions (K⁺, Na⁺, Li⁺) and eight amino acids (Lys, Arg, Ala, Gly, Val, Thr, Trp, Asp) are detected using back scatter interferometry (BSI), without the need for chemical modifications or contrast. ...
DOI:
10.1039/d0ay02218g

26. Dispersive liquid–liquid microextraction method for the extraction of acidic pesticides in edible oils; application of short-chain organic acids as co–disperser and protonation agent

Author:
Payam Gonbari Milani; Mohammadali Torbati; Mir Ali Farajzadeh; Ali Mohebbi; Mohammad Reza Afshar Mogaddam
Source:
International journal of environmental analytical chemistry 2022 v.102 no.3 pp. 667-680
ISSN:
1029-0397
Subject:
acetic acid; analytical chemistry; chemical species; cooking fats and oils; fenoxaprop; fluazifop; haloxyfop; liquid-phase microextraction; methylene chloride; pH; protonation; sodium hydroxide; solvents
Abstract:
... In the present study, a sample pretreatment based on the combination of vortex assisted liquid–liquid extraction and dispersive liquid–liquid microextraction has been proposed for the isolation and preconcentration of three acidic herbicides including fenoxaprop, fluazifop, and haloxyfop from edible oil samples. For this purpose, firstly, the analytes were extracted into sodium hydroxide solution ...
DOI:
10.1080/03067319.2020.1724991

27. Effect of Acetic Acid Addition on Decomposition of Xylose in Supercritical Water

Author:
Tanawan Chalermsaktrakul; Yukihiko Matsumura
Source:
Energy & fuels 2018 v.32 no.2 pp. 1754-1760
ISSN:
1520-5029
Subject:
acetic acid; carbon; chemical species; free radicals; fuels; furfural; gasification; hemicellulose; ions; models; xylose; xylulose
Abstract:
... The supercritical water gasification of xylose, a model substrate for hemicellulose, was carried out at 400 and 450 °C and at a constant pressure of 25 MPa in the presence of acetic acid using a continuous flow reactor. More specifically, we aimed to compare the reaction rate constants of xylose decomposition in both the presence and absence of acetic acid. Upon the application of a residence time ...
DOI:
10.1021/acs.energyfuels.7b02720

28. Effects of storage on the sequential extraction of micronutrients and trace elements in fruit and vegetable residue flour

Author:
Luana Sarpa Reis; Édira C. B. A. Gonçalves
Source:
Chemical speciation and bioavailability 2014 v.26 no.4 pp. 278-285
ISSN:
0954-2299
Subject:
acetic acid; ammonium acetate; bioavailability; calcium chloride; chemical species; chemical structure; copper; extractors; flour; fruits; iron; magnesium; manganese; pH; pomace; vegetable residues; vegetables; zinc
Abstract:
... Sequential extraction consists of the use of a number of extractors with different chemical properties that are progressively applied to a sample. The objective of this study was to evaluate the influence of sequential extraction of Cu, Fe, Mn, Mg and Zn from fruit and vegetable residue flour during storage for up to 60 days. The following extractors were applied: 1M calcium chloride, 0.1M acetic ...
DOI:
10.3184/095422914X14142395856286

29. Electric field-assisted multiphase extraction to increase selectivity and sensitivity in liquid chromatography-mass spectrometry and paper spray mass spectrometry

Author:
Millena Christie Ferreira Avelar; Clesia Cristina Nascentes; Ricardo Mathias Orlando
Source:
Talanta 2021 v.224 pp. 121887
ISSN:
0039-9140
Subject:
acetic acid; acetonitrile; antidepressants; chemical species; detection; electric field; electrolytes; extraction; liquid chromatography; liquid membranes; mass spectrometry; precision; screening; solvents; standard deviation; toxicity testing
Abstract:
... In this work, for the first time, chromatographic paper was used for a multiphase extraction assisted by an electric field (MPEF) and directly coupled to paper spray mass spectrometry (PS-MS). Using this approach, five tricyclic antidepressants (TCAs) were determined in oral fluid. Firstly, the MPEF conditions were optimized using liquid chromatography-mass spectrometry (LC-MS/MS). The effects of ...
DOI:
10.1016/j.talanta.2020.121887

30. Enrichment-free analysis of anionic micropollutants in the sub-ppb range in drinking water by capillary electrophoresis-high resolution mass spectrometry

Author:
Oliver Höcker; Tobias Bader; Torsten C. Schmidt; Wolfgang Schulz; Christian Neusüß
Source:
Analytical and bioanalytical chemistry 2020 v.412 no.20 pp. 4857-4865
ISSN:
1618-2642
Subject:
acesulfame potassium; acetic acid; analytical chemistry; capillary electrophoresis; chemical species; disinfection; electrolytes; environmental assessment; isopropyl alcohol; liquids; mass spectrometry; perfluorooctane sulfonic acid; phosphates; pollutants; reversed-phase liquid chromatography; silica; spectrometers; standard deviation; sulfates; water analysis
Abstract:
... Reversed-phase liquid chromatography (RPLC) used for water analysis is not ideal for the analysis of highly polar and ionic contaminants because of low retention. Capillary electrophoresis (CE), on the other hand, is perfectly suited for the separation of ionic compounds but rarely applied in environmental analysis due to the weak concentration sensitivity when coupled to mass spectrometry (MS). H ...
DOI:
10.1007/s00216-020-02525-8

31. Environmental impact of molecularly imprinted polymers used as analyte sorbents in mass spectrometry

Author:
Maria Guć; Beata Messyasz; Grzegorz Schroeder
Source:
Science of the total environment 2021 v.772 pp. 145074
ISSN:
0048-9697
Subject:
2,4-D; Daphnia magna; Tetradesmus; acetic acid; acrylamides; atmospheric pressure; chemical species; cross-linking reagents; detection limit; environment; environmental impact; ethylene glycol; mass spectrometry; methanol; molecular imprinting; polymerization; polymers; quercetin; rutin; solvents; sorbents; toxicity
Abstract:
... The molecularly imprinted polymers (MIPs) with the following herbicides used as templates 2,4-dichlorophenoxyacetic acid (2,4-D) or 4-chloro-2-methylphenoxy- acetic acid (MCPA) were synthesized by precipitation polymerization technique using 4-vinylpyridine (4-VP) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linking agent, and 2,2′-azobisisobutyronitrile (AIBN) as an ...
DOI:
10.1016/j.scitotenv.2021.145074

32. Evaluation of a nanoflow interface based on the triple-tube coaxial sheath-flow sprayer for capillary electrophoresis-mass spectrometry coupling in metabolomics

Author:
Sabrina Ferré; Nicolas Drouin; Víctor González-Ruiz; Serge Rudaz
Source:
Journal of chromatography 2021 v.1641 pp. 461982
ISSN:
0021-9673
Subject:
acetic acid; alanine; capillary electrophoresis; chemical species; chromatography; liquids; mass spectrometry; metabolomics; methionine; pH; sprayers; tyrosine; valine
Abstract:
... The performance of an original CE-MS interface that allows the in-axis positioning of the electrospray with respect to the MS inlet was evaluated. The variations in the geometrical alignment of this configuration in the absence of a nebulizing gas afforded a significant reduction in the sheath-liquid flow rate from 3 µL/min to as low as 300 nL/min. The sheath liquid and BGE were respectively compo ...
DOI:
10.1016/j.chroma.2021.461982

33. Extraction of phthalic acid esters from soft drinks and infusions by dispersive liquid-liquid microextraction based on the solidification of the floating organic drop using a menthol-based natural deep eutectic solvent

Author:
Cecilia Ortega-Zamora; Gabriel Jiménez-Skrzypek; Javier González-Sálamo; Javier Hernández-Borges
Source:
Journal of chromatography 2021 v.1646 pp. 462132
ISSN:
0021-9673
Subject:
Mentha pulegium; acetic acid; chemical species; dibutyl phthalate; green tea; high performance liquid chromatography; lemons; liquid-phase microextraction; mint; phthalic acid; solidification; solvents; standard deviation
Abstract:
... In this work, a natural deep eutectic solvent (NADES) consisting of L-menthol and acetic acid in a 1:1 molar ratio has been applied as extraction solvent for the dispersive liquid-liquid microextraction based on the solidification of the floating organic drop (DLLME-SFO) of a group of nine phthalic acid esters (dipropyl phthalate, DPP; butyl benzyl phthalate, BBP; dibutyl phthalate, DBP; dicyclohe ...
DOI:
10.1016/j.chroma.2021.462132

34. Facile synthesis of molecularly imprinted polymers for selective extraction of tyrosine metabolites in human urine

Author:
Xianyu Liang; Fan Liu; Yiqun Wan; Xiaoying Yin; Weiting Liu
Source:
Journal of chromatography 2019 v.1587 pp. 34-41
ISSN:
0021-9673
Subject:
acetic acid; acetonitrile; biomarkers; chemical species; detection limit; fluorescence; high performance liquid chromatography; lactic acid; metabolites; molecular imprinting; polymerization; polymers; quantitative analysis; tyrosine; ultra-performance liquid chromatography; urine
Abstract:
... In this study a method is developed for quantitative analysis of three potential biomarkers, including 4-hydroxyphenyl acetic acid (PHPAA), 4-hydroxyphenyl lactic acid (PHPLA) and 3,4-hydroxyphenylpropionic acid (PHPA), in human urine. Molecular imprinted polymers (MIPs) as the sample clean up materials were applied to selectively extract these tyrosine metabolites, followed by precise detection u ...
DOI:
10.1016/j.chroma.2018.12.014

35. Fast Optimization of Supercritical Fluid Chromatography–Mass Spectrometry Interfacing Using Prediction Equations

Author:
Kateřina Plachká; Tat’ána Gazárková; Jan Škop; Davy Guillarme; Frantisek Svec; Lucie Nováková
Source:
Analytical chemistry 2022 v.94 no.11 pp. 4841-4849
ISSN:
1520-6882
Subject:
acetic acid; ammonia; ammonium; analytical chemistry; chemical species; electrospray ionization mass spectrometry; hydrogen; methanol; molecular weight; prediction; regression analysis; solvents
Abstract:
... The effect of makeup solvent composition in ultrahigh-performance supercritical fluid chromatography-triple quadrupole mass spectrometry using electrospray ionization was studied using a set of 91 compounds, 3 stationary phases, and 2 organic modifiers of the mobile phase. The 24 tested makeup solvents included pure alcohols and methanol in combination with commonly used additives such as water, f ...
DOI:
10.1021/acs.analchem.2c00154

36. Fast analysis of glufosinate, glyphosate and its main metabolite, aminomethylphosphonic acid, in edible oils, by liquid chromatographycoupled with electrospray tandem mass spectrometry

Author:
Marilda Chiarello; María Luisa Jiménez-Medina; Jesús Marín Saéz; Sidnei Moura; Antonia Garrido Frenich; Roberto Romero-González
Source:
Food additives & contaminants 2019 v.36 no.9 pp. 1376-1384
ISSN:
1944-0057
Subject:
acetic acid; chemical species; cooking fats and oils; electrospray ionization mass spectrometry; formic acid; glufosinate; glyphosate; herbicide resistance; ionization; liquid chromatography; liquids; metabolites; methanol; tandem mass spectrometry
Abstract:
... A method has been developed for the rapid, specific, accurate, precise and sensitive determination of glufosinate, glyphosate and its major metabolite, aminomethylphosphonic acid, in edible oils, by liquid chromatography coupled to tandem mass spectrometry. Oils were extracted with acidified water (1% formic acid), and the extracts were directly injected into an LC using a Hypercarb column as the ...
DOI:
10.1080/19440049.2019.1631493

37. Highly Ordered Polymer Nanostructures via Solvent On-Film Annealing for Surface-Enhanced Raman Scattering

Author:
Kai-Jie Chang; Huan-Ru Chen; Chiang-Hung Hung; Pei-Sung Hung; Hsiao-Fan Tseng; Yu-Liang Lin; Hsun-Hao Hsu; Tzu-Hsun Kao; Pu-Wei Wu; Ian Liau; Jiun-Tai Chen
Source:
Langmuir 2021 v.38 no.2 pp. 801-809
ISSN:
1520-5827
Subject:
acetic acid; calibration; chemical species; cyclohexanes; detection limit; emulsions; nanogold; nanospheres; polymerization; polystyrenes; rhodamines; solvents
Abstract:
... Surface-enhanced Raman scattering (SERS) has been a useful sensing technique, in which inelastic light scattering can be significantly enhanced by absorbing molecules onto rough metal surfaces or nanoparticles. Although many methods have been developed to prepare SERS substrates, it is still highly desirable and challenging to design SERS substrates, especially with highly ordered and controlled t ...
DOI:
10.1021/acs.langmuir.1c02818

38. Identification and validation of small molecule analytes in mouse plasma by liquid chromatography–tandem mass spectrometry: A case study of misidentification of a short-chain fatty acid with a ketone body

Author:
Mariel A. García-Rivera; Álvaro Fernández-Ochoa; Ulrike Brüning; Raphaela Fritsche-Guenther; Jennifer A. Kirwan
Source:
Talanta 2022 v.242 pp. 123298
ISSN:
0039-9140
Subject:
3-hydroxybutyric acid; acetic acid; biomarkers; case studies; chemical species; diabetes; immune response; ketone bodies; metabolomics; mice; risk reduction; tandem mass spectrometry
Abstract:
... Recently, there has been growing interest in short-chain fatty acids (SCFA) and ketone bodies (KB) due to their potential use as biomarkers of health and disease. For instance, these diet-related metabolites can be used to monitor and reduce the risk of immune response, diabetes, or cardiovascular diseases. Given the interest in these metabolites, different targeted metabolomic methods based on UP ...
DOI:
10.1016/j.talanta.2022.123298

39. LC-MS/MS Determination of Tropane Alkaloids in Maize Crop

Author:
Gorica Vuković; Vojislava Bursić; Tijana Stojanović; Aleksandra Petrović; Sonja Gvozdenac; Mira Starović; Slobodan Kuzmanović; Goran Aleksić
Source:
Contemporary Agriculture 2018 v.67 no.3-4 pp. 221-226
ISSN:
2466-4774
Subject:
acetic acid; acetonitrile; atropine; chemical species; corn; liquid chromatography; magnesium sulfate; methanol; scopolamine; sodium chloride; sodium citrate; tandem mass spectrometry
Abstract:
... The undemanding LC-MS/MS method was developed for the synchronized analysis of atropine and scopolamine in maize crop. The dSPE was carried out with 1% acetic acid in acetonitrile/water and a mixture of magnesium sulphate, sodium chloride and sodium citrate. The analytes were separated on a Zorbax XDB C18 column using methanol/water as the mobile phase in gradient mode. The detection was done usin ...
DOI:
10.1515/contagri-2018-0032

40. Large volume sample stacking of antiepileptic drugs in counter current electrophoresis performed in PAMAPTAC coated capillary

Author:
Petr Tůma; Tomáš Hložek; Blanka Sommerová; Dušan Koval
Source:
Talanta 2021 v.221 pp. 121626
ISSN:
0039-9140
Subject:
acetic acid; acetonitrile; acrylamides; anticonvulsants; area; blood serum; chemical bonding; chemical species; chlorides; composite polymers; electric potential difference; electroosmosis; electrophoresis; flow; humans; length; precision; separation; silica; volume; zwitterions
Abstract:
... Electrophoretic stacking is developed for sensitive determination of three zwitterionic antiepileptics, namely vigabatrin, pregabalin and gabapentin, in human serum. CE separation is performed in a 25 μm fused silica capillary covalently coated with the copolymer of acrylamide with 5% content of permanently charged 3-acrylamidopropyl trimethylammonium chloride (PAMAPTAC). In background electrolyte ...
DOI:
10.1016/j.talanta.2020.121626

41. Laser-Induced Carbon-Based Smart Flexible Sensor Array for Multiflavors Detection

Author:
Yongchao Yu; Pooran C. Joshi; Jayne Wu; Anming Hu
Source:
ACS applied materials & interfaces 2018 v.10 no.40 pp. 34005-34012
ISSN:
1944-8252
Subject:
acetic acid; carbon; carbon electrodes; carbonization; chemical species; coatings; detection limit; electronic tongue; flavor; gold; humans; polyamides; prediction; principal component analysis; sodium chloride; sugars; vinegars
Abstract:
... We report a flexible sensor array electronic tongue system that is fabricated on a polymer substrate by the laser direct writing process for multiflavor detection. Electronic tongue is a sensing system that is applied to detect different elements with the same sensor array. By analyzing responses from different measurement units, it enables a cross-sensitivity, namely, the ability of the system to ...
DOI:
10.1021/acsami.8b12626

42. Liquid chromatography-mass spectrometry-based determination of ergocristine, ergocryptine, ergotamine, ergovaline, hypoglycin A, lolitrem B, methylene cyclopropyl acetic acid carnitine, N-acetylloline, N-formylloline, paxilline, and peramine in equine hair

Author:
Wiebke Rudolph; Daniela Remane; Dirk K. Wissenbach; Frank T. Peters
Source:
Journal of chromatography 2019 v.1117 pp. 127-135
ISSN:
1570-0232
Subject:
acetic acid; ammonium; carnitine; chemical species; chronic exposure; detection limit; ergotamine; ergovaline; fungi; grasses; grazing; high performance liquid chromatography; horses; hydrophilic interaction chromatography; ingestion; mass spectrometry; metabolites; monitoring; pasture plants; pastures; paxilline; seeds
Abstract:
... Ingestion of hypoglycin A (HGA) in maple seeds or alkaloids produced by symbiotic fungi in pasture grasses is thought to be associated with various syndromes in grazing animals. This article describes analytical methods for monitoring long-term exposure to HGA, its metabolite MCPA-carnitine, as well as ergocristine, ergocryptine, ergotamine, ergovaline, lolitrem B, N-acetylloline, N-formylloline, ...
DOI:
10.1016/j.jchromb.2019.04.016

43. Magnetic zinc based 2D-metal organic framework as an efficient adsorbent for simultaneous determination of fluoroquinolones using 3D printed microchip and liquid chromatography tandem mass spectrometry

Author:
Nafiseh Bagheri; Haider A.J. Al Lawati; Nada A. Al Sharji; Javad Hassanzadeh
Source:
Talanta 2021 v.224 pp. 121796
ISSN:
0039-9140
Subject:
acetic acid; adsorbents; chemical species; ciprofloxacin; coordination polymers; detection limit; high performance liquid chromatography; magnetic materials; magnetism; microchip technology; milk; norfloxacin; ofloxacin; sampling; solid phase extraction; solvents; surface area; tandem mass spectrometry; toxicity; zinc
Abstract:
... Herein, a two dimensional metal-organic framework (2D MOF) is introduced as an efficient adsorbent for simultaneously extraction of fluoroquinolones (FQs) from milk samples. The proposed MOF was synthesized by solvothermal method. The high surface area and high accessible sites of prepared MOF offered a unique adsorbent for solid phase extraction (SPE). The experiments showed the great ability of ...
DOI:
10.1016/j.talanta.2020.121796

44. Menthol-Based Deep Eutectic Solvent Dispersive Liquid–Liquid Microextraction: A Simple and Quick Approach for the Analysis of Phthalic Acid Esters from Water and Beverage Samples

Author:
Cecilia Ortega-Zamora; Javier González-Sálamo; Cintia Hernández-Sánchez; Javier Hernández-Borges
Source:
ACS sustainable chemistry & engineering 2020 v.8 no.23 pp. 8783-8794
ISSN:
2168-0485
Subject:
acetic acid; acidity; agitation; apple juice; beverages; biodegradability; centrifugation; chemical species; chromatography; dibutyl phthalate; differential scanning calorimetry; droplets; hydrochloric acid; infrared spectroscopy; liquid-phase microextraction; mineral water; solubilization; solvents; standard deviation; tap water; toxicity
Abstract:
... In this work, a natural deep eutectic solvent (NADES) composed of l-menthol:acetic acid 1:1 (molar ratio) was applied for the first time as the extraction solvent for the dispersive liquid–liquid microextraction (DLLME) of a group of 9 phthalic acid esters (i.e., dipropyl phthalate, DPP; butyl benzyl phthalate, BBP; dibutyl phthalate, DBP; diisopentyl phthalate, DIPP; di-n-pentyl phthalate, DNPP; ...
DOI:
10.1021/acssuschemeng.0c02603

45. Multi-residue screening of 100 multi-class veterinary drugs in milk powder by liquid chromatography coupled to quadrupole time-of-flight mass spectrometry

Author:
Jian Kang; Chun-Lin Fan; Ya-Fei Cao; Hui-Jun Wang; Xing Peng; Zhi-Bin Wang; Qiao-Ying Chang; Xue-Yan Hu; Guo-Fang Pang
Source:
Analytical methods 2014 v.6 no.20 pp. 8337-8349
ISSN:
1759-9679
Subject:
acetic acid; acetonitrile; benzimidazoles; beta-adrenergic agonists; chemical species; dried milk; elemental composition; hormones; ions; liquid chromatography; macrolides; nitroimidazoles; pH; quinolones; screening; sorbents; sulfonamides; tandem mass spectrometry; tetracyclines; tranquilizers; veterinary drugs
Abstract:
... In this study, a simple and rapid multi-residue screening method for the quantification and confirmation of 100 multi-class veterinary drugs in milk powder by the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method combined with liquid chromatography coupled to quadrupole time-of-flight mass spectrometry was developed. The veterinary drugs investigated belonged to several families su ...
DOI:
10.1039/c4ay01627k

46. Multiclass Analytical Method for Pesticide and Mycotoxin Analysis in Malt, Brewers’ Spent Grain, and Beer: Development, Validation, and Application

Author:
Nilsrael Alves Pires; Mauro Lucio Gonçalves De Oliveira; José Ailton Gonçalves; Adriana Ferreira Faria
Source:
Journal of agricultural and food chemistry 2021 v.69 no.15 pp. 4533-4541
ISSN:
1520-5118
Subject:
acetic acid; acetonitrile; beers; centrifugation; chemical species; food chemistry; homogenization; laws and regulations; malt; mycotoxins; pesticides; spent grains; tandem mass spectrometry; uncertainty
Abstract:
... A multiclass analytical method to determine pesticides and mycotoxins in beer-related matrices based on the dilute and shoot approach was optimized and validated according to the European guidelines SANTE/12682/2019 and EC/401/2006. Extraction used acidified acetonitrile at 1% (v/v) acetic acid, followed by horizontal shaking homogenization, centrifugation, freeze-out step for cleanup, another cen ...
DOI:
10.1021/acs.jafc.0c07004

47. Multivariate optimization of ultrasound-assisted extraction using Doehlert matrix for simultaneous determination of Fe and Ni in vegetable oils by high-resolution continuum source graphite furnace atomic absorption spectrometry

Author:
Jorge S. Almeida; Gabriel L. Santos; Geovani C. Brandão; Maria G.A. Korn; Leonardo S.G. Teixeira
Source:
Food chemistry 2019 v.273 pp. 130-135
ISSN:
0308-8146
Subject:
acetic acid; atomic absorption spectrometry; chemical species; hydrochloric acid; iron; nickel; solvents; sonication; temperature; ultrasonic treatment; vegetable oil
Abstract:
... A method for simultaneous determination of Fe (232.036 nm) and Ni (232.195 nm) in vegetable oil samples by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) after an acid extraction of the analytes is proposed. In the extraction step, hydrochloric, nitric and acetic acid solutions were tested. The optimization of the procedure was performed by applying ...
DOI:
10.1016/j.foodchem.2018.01.112

48. NACE–ESI‐MS/MS method for separation and characterization of phosphorylation and acylation isomers of lipid A

Author:
Viktor Sándor; Balázs Viktor Berkics; Anikó Kilár; Béla Kocsis; Ferenc Kilár; Ágnes Dörnyei
Source:
Electrophoresis 2020 v.41 no.13-14 pp. 1178-1188
ISSN:
0173-0835
Subject:
acetic acid; acylation; bacterial outer membranes; chemical species; electrophoresis; isomerization; lipid A; methanol; methylene chloride; pathogenesis; phosphorylation; therapeutics; triethylamine
Abstract:
... Lipid A represents a heterogeneous group of bacterial outer membrane phosphoglycolipids, which play a major role in the pathogenesis of Gram‐negative sepsis. The number and position of phosphoryl and acyl groups in lipid A molecules are key structural determinants in their bioactivities. In this study, a NACE–ESI‐MS/MS method was developed for the simultaneous analysis of lipid A isomers possessin ...
DOI:
10.1002/elps.201900251

49. Optimization of a method to detect levothyroxine and related compounds in serum and urine by liquid chromatography coupled to triple quadrupole mass spectrometry

Author:
Dayamin Martínez_Brito; Patrizia Leogrande; Xavier de la Torre; Francesco Botrè
Source:
Journal of pharmacological and toxicological methods 2022 v.115 pp. 107169
ISSN:
1056-8719
Subject:
Escherichia coli; Helix pomatia; L-thyroxine; acetic acid; ammonium; blood serum; chemical species; electric potential difference; electrospray ionization mass spectrometry; fluorides; formates; formic acid; hexane; hydrolysis; ionization; isopropyl alcohol; liquid chromatography; liquid-liquid extraction; methyl ethers; solvents; temperature; thyronine; toxicology; tyrosine; urine
Abstract:
... Thyroid hormones and their derivatives are structurally related to the non-essential amino acid tyrosine (4-hydroxyphenylalanine). However, there are physicochemical differences that make it difficult to apply an analytical method for their simultaneous detection. This work focused on the optimization of a method using liquid chromatography-electrospray ionization mass spectrometry to measure eigh ...
DOI:
10.1016/j.vascn.2022.107169

50. Organic acids and alcohols quantification by HPLC/RID in sugarcane vinasse: analytical method validation and matrix effect assessment

Author:
Alan Nascimento Bernardes; Leandro Augusto Gouvêa Godoi; Priscila Rosseto Camiloti; Absai da Conceição Gomes; Bruna Larissa Sandy Sanchez; Ana Paula Rodrigues Torres; Lívia Silva Botta
Source:
International journal of environmental analytical chemistry 2021 v.101 no.3 pp. 325-336
ISSN:
1029-0397
Subject:
acetic acid; alcoholic fermentation; analytical chemistry; butanol; butyric acid; chemical species; citric acid; ethanol; glycerol; hexanoic acid; high performance liquid chromatography; lactic acid; methanol; molasses; propionic acid; refractive index; succinic acid; sugarcane juice; valeric acid; vinasse; wastewater
Abstract:
... The composition of sugarcane vinasse varies according to the substrate of alcoholic fermentation, e.g. if it is sugarcane juice and/or molasses. Regardless of the origin, the main organic compounds found in sugarcane vinasse are organic acids, alcohols and a low amount of carbohydrates. To access the organic composition of such wastewater, the present paper describes a high-performance liquid chro ...
DOI:
10.1080/03067319.2019.1666833