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1. Use of Rapid Capillary Zone Electrophoresis to Determine Amino Acids Indicators of Herring Ripening during Salting

Author:
Katarzyna Felisiak; Mariusz Szymczak
Source:
Foods 2021 v.10 no.11 pp. -
ISSN:
2304-8158
Subject:
acetic acid; capillary zone electrophoresis; cluster analysis; derivatization; herring; hydrophobicity; industry; labor; meat; muscles; nonprotein nitrogen; principal component analysis; proteinases; proteolysis; regression analysis; salted fish; sensory evaluation; texture; trichloroacetic acid
Abstract:
... Currently, herring fillets are salted with acetic acid to activate muscle proteases. This causes a change in the composition of free amino acids, compared to salting of whole fish with viscera proteases. Therefore, old indicators of the ripening dynamics of salted fish based on amino acids are not current. Determination of free amino acids can be performed by many methods, but most are labor inten ...
DOI:
10.3390/foods10112518

2. Characterization of E 472 food emulsifiers by high-performance thin-layer chromatography with fluorescence detection and mass spectrometry

Author:
Claudia Oellig; Katharina Link; Wolfgang Schwack
Source:
Journal of chromatography 2020 v.1618 pp. 460874
ISSN:
0021-9673
Subject:
acetic acid; citric acid; dairy products; derivatization; diacetyl; diacylglycerols; emulsifiers; emulsions; fluorescence; foaming; food additives; food industry; free fatty acids; fruit acids; glycerol; lactic acid; mass spectrometry; silica gel; tartaric acid; thin layer chromatography; triacylglycerols; viscosity
Abstract:
... Esters of fruit acids including acetic acid and mono- and diacylglycerols (MAG and DAG), also known as E 472 emulsifiers, are used in the food industry as food additives to adjust techno-functional properties like viscosity, emulsion stability and foaming stability in various products, mainly dairy products. Based on the respective acids, E 472 emulsifiers are classified in several categories with ...
DOI:
10.1016/j.chroma.2020.460874

3. Preparation of imidazolidinone compounds as derivatization reagent for diastereomerization and chromatographic separation of chiral organic acids

Author:
Maho Umino; Tatsuya Sakamoto; Mayu Onozato; Takeshi Fukushima
Source:
Journal of chromatography 2022 v.1675 pp. 463159
ISSN:
0021-9673
Subject:
3-hydroxybutyric acid; acetic acid; derivatization; diastereomerism; lactic acid; malic acid; moieties; succinic acid; tartaric acid; wines
Abstract:
... A chiral derivatization reagent for application in LC-tandem mass spectrometry (LC-MS/MS)-based detection, benzyl 5-(2-aminoethyl)-3-methyl-4-oxoimidazolidine-1-carboxylate (CIM-C₂-NH₂), which can react with the carboxyl group, was synthesized. Both chiral and non-chiral organic acids such as lactic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, acetic acid, succinic acid, tartaric acid, mali ...
DOI:
10.1016/j.chroma.2022.463159

4. 3‐(4‐Carboxybenzoyl)quinoline‐2‐carboxaldehyde labeling for direct analysis of amino acids in plasma is not suitable for simultaneous quantification of tryptophan, tyrosine, valine, and isoleucine by CE/fluorescence

Author:
Hai Yen Ta; Lucie Perquis; Cédric Sarazin; Bruno Guiard; Varravaddheay Ong Meang; Fabrice Collin; François Couderc
Source:
Electrophoresis 2021 v.42 no.9-10 pp. 1108-1114
ISSN:
0173-0835
Subject:
acetic acid; capillary electrophoresis; derivatization; electrolytes; fluorescence; isoleucine; mice; pH; quantitative analysis; tryptophan; tyrosine; valine
Abstract:
... Capillary electrophoresis coupled to LED‐induced fluorescence detection is a robust and sensitive technique used for amino acids (AA) analysis in biological media, after labeling with 3‐(4‐carboxybenzoyl)quinoline‐2‐carboxaldehyde (CBQCA). We wanted to quantitate in plasma tryptophan (Trp), tyrosine (Tyr), valine (Val), and isoleucine (Ile). Among the different labeled AA‐CBQCA, Trp has the lowest ...
DOI:
10.1002/elps.202000263

5. A novel charge derivatization-direct infusion mass spectrometry method for the quantitative analysis of C1–C8 fatty acids in rubber seed oil-based biodiesel

Author:
Hua-Ming Xiao; Yan Shi; Yong-Xue Yang; Shuai Zhao; Xian Wang
Source:
Talanta 2021 v.226 pp. 122107
ISSN:
0039-9140
Subject:
acetic acid; biodiesel; catalysts; derivatization; detection limit; fatty acids; formic acid; free fatty acids; mass spectrometry; monitoring; oxidation; propionic acid; quantitative analysis; rubber; rubber seed oil; sampling
Abstract:
... The free fatty acids that contain one to eight carbons (C₁–C₈) in biodiesel would affect the quality of biodiesel. It is still a matter of challenge to simultaneously determine the composition of C₁–C₈ fatty acids in seed oil and seed oil-based biodiesel. Herein, a novel method of charge derivatization coupling with direct infusion mass spectrometry (CD-DIMS) was developed for the determination of ...
DOI:
10.1016/j.talanta.2021.122107

6. A sensitive GC/MS detection method for analyzing microbial metabolites short chain fatty acids in fecal and serum samples

Author:
Shuming Zhang; Hongbin Wang; Mei-Jun Zhu
Source:
Talanta 2019 v.196 pp. 249-254
ISSN:
0039-9140
Subject:
acetic acid; blood serum; butyric acid; derivatization; detection limit; digestive system; gas chromatography-mass spectrometry; homeostasis; intestinal microorganisms; isobutyric acid; metabolic diseases; metabolites; mice; monitoring; propionic acid; sodium sulfate; temperature; valeric acid; volatile compounds
Abstract:
... Gut microbiota and their major metabolites, short-chain fatty acids (SCFAs), are recognized as important players in gut homeostasis and metabolic disease occurance. A convenient and sensitive detection method is needed to profile SCFAs in limited and complex biological samples. The gas chromatography/mass spectrometry (GC/MS) is the most common method for SCFAs profiling in biological samples. Tri ...
DOI:
10.1016/j.talanta.2018.12.049
CHORUS:
10.1016/j.talanta.2018.12.049

7. A simulated strategy for analysis of Short- to Long- chain fatty acids in mouse serum beyond chemical standards

Author:
Xueying Wang; Huabin Ruan; Zhaoyun Zong; Fengfeng Mao; Yusong Wang; Yupei Jiao; Lina Xu; Tao Yang; Wenhui Li; Xiaohui Liu
Source:
Journal of chromatography 2021 v.1180 pp. 122895
ISSN:
1570-0232
Subject:
acetic acid; blood serum; chromatography; derivatization; detection limit; gender; mass spectrometry; mice; palmitic acid
Abstract:
... Broadening coverage in fatty acid (FA) analysis benefits the understanding of metabolic regulation in biological system. However, the limited access of chemical standards makes it challenging. In this work, we introduced a simulation assisted strategy to analyze short-, medium-, long- and very-long-chain fatty acids beyond the use of chemical standards. This targeted analysis in selected reaction ...
DOI:
10.1016/j.jchromb.2021.122895

8. Capillary electrochromatography-mass spectrometry of kynurenine pathway metabolites

Author:
A.S.M.M.R. Chawdhury; Shahab A. Shamsi; Andrew Miller; Aimin Liu
Source:
Journal of chromatography 2021 v.1651 pp. 462294
ISSN:
0021-9673
Subject:
C-reactive protein; acetic acid; anthranilic acid; biomarkers; chromatography; derivatization; detection limit; electric potential difference; electrolytes; humans; kynurenine; kynurenine pathway; metabolites; pH; patients; picolinic acid; polymerization; silica; tryptamine; tryptophan; tumor necrosis factor-alpha; xanthurenic acid
Abstract:
... Few articles are reported for the simultaneous separation and sensitive detection of the kynurenine pathway (KP) metabolites. This work describes a capillary electrochromatography-mass spectrometry (CEC-MS) method using acrylamido-2-methyl-1-propanesulfonic acid (AMPS) functionalized stationary phase. The AMPS column was prepared by first performing silanization of bare silica with gamma-maps, fol ...
DOI:
10.1016/j.chroma.2021.462294

9. Determination of 1-Deoxynojirimycin by a developed and validated HPLC-FLD method and assessment of In-vitro antioxidant, α-Amylase and α-Glucosidase inhibitory activity in mulberry varieties from Turkey

Author:
Nuraniye Eruygur; Emrah Dural
Source:
Phytomedicine 2019 v.53 pp. 234-242
ISSN:
0944-7113
Subject:
2,2-diphenyl-1-picrylhydrazyl; Morus alba; Morus nigra; acetic acid; acetonitrile; active ingredients; alpha-amylase; alpha-glucosidase; antioxidant activity; deoxynojirimycin; derivatization; drugs; enzyme activity; enzyme inhibition; ethanol; flavonoids; fluorescence; fluorometry; foods; gas chromatography-mass spectrometry; glycemic effect; herbal tea; leaves; mulberries; reversed-phase high performance liquid chromatography; Turkey (country)
Abstract:
... Morus alba and Morus nigra leaves which have been widely used as herbal teas in Anatolian region of Turkey, were extracted twice by 50 mM HCI solution, derivatized with 9-fluorenylmethyl chloroformate and analyzed by reversed phase HPLC equipped with a fluorescence detector.This study was performed to determine the main antidiabetic active compounds 1-deoxynojirimycin by HPLC method and evaluate t ...
DOI:
10.1016/j.phymed.2018.09.016

10. Development of a Simple and Sensitive Pre-column Derivatization HPLC Method for the Quantitative Analysis of Miglitol Intermediates

Author:
Neng Xiong; Qian Li; Yan Dong; Sheng Wei; Zhongce Hu; Yaping Xue; Yuguo Zheng
Source:
Chromatographia 2021 v.84 no.4 pp. 347-358
ISSN:
0009-5893
Subject:
acetic acid; acetonitrile; aqueous solutions; biotransformation; derivatization; hypoglycemic agents; pH; quantitative analysis; sodium borate
Abstract:
... In the synthesis of hypoglycemic agent miglitol, the quantitative analysis of two key intermediates, N-2-hydroxyethyl glucamine and 6-(N-hydroxyethyl)-amino-6-deoxy-alpha-L-sorbofuranose, has long been a challenge. In this study, derivatization reagents were screened, and then a novel HPLC method coupled with 9-fluorenylmethyl chloroformate derivatization was developed for the quantitative analysi ...
DOI:
10.1007/s10337-021-04010-5

11. Microwave-assisted synthesis of 4-oxo-2-butenoic acids by aldol-condensation of glyoxylic acid

Author:
Mélanie Uguen; Conghao Gai; Lukas J. Sprenger; Hang Liu; Andrew G. Leach; Michael J. Waring
Source:
RSC advances 2021 v.11 no.48 pp. 30229-30236
ISSN:
2046-2069
Subject:
acetic acid; condensation reactions; derivatization; glyoxylic acid; microwave treatment
Abstract:
... 4-Oxobutenoic acids are useful as biologically active species and as versatile intermediates for further derivatisation. Currently, routes to their synthesis can be problematic and lack generality. Reaction conditions for the synthesis of 4-oxo-2-butenoic acid by microwave-assisted aldol-condensation between methyl ketone derivatives and glyoxylic acid have been developed. They provide the desired ...
DOI:
10.1039/d1ra05539a

12. Molecular Functionalization of 2H-Phase MoS₂ Nanosheets via an Electrolytic Route for Enhanced Catalytic Performance

Author:
S. García-Dalí; J. I. Paredes; S. Villar-Rodil; A. Martínez-Jódar; A. Martínez-Alonso; J. M. D. Tascón
Source:
ACS applied materials & interfaces 2021 v.13 no.28 pp. 33157-33171
ISSN:
1944-8252
Subject:
acetic acid; aniline; catalysts; catalytic activity; derivatization; dyes; electrolytes; nanosheets; nitroaromatic compounds; polymers; remediation; sulfur; synthesis; thermodynamics
Abstract:
... The molecular functionalization of two-dimensional MoS₂ is of practical relevance with a view to, for example, facilitating its liquid-phase processing or enhancing its performance in target applications. While derivatization of metallic 1T-phase MoS₂ nanosheets has been relatively well studied, progress involving their thermodynamically stable, 2H-phase counterpart has been more limited due to th ...
DOI:
10.1021/acsami.1c08850

13. Sensomics-Assisted Flavor Decoding of Dairy Model Systems and Flavor Reconstitution Experiments

Author:
Florian Utz; Johanna Kreissl; Timo D. Stark; Christian Schmid; Caren Tanger; Ulrich Kulozik; Thomas Hofmann; Corinna Dawid
Source:
Journal of agricultural and food chemistry 2021 v.69 no.23 pp. 6588-6600
ISSN:
1520-5118
Subject:
acetaldehyde; acetic acid; acetoin; butyric acid; citric acid; derivatization; desserts; diacetyl; dimethyl sulfide; flavor; food chemistry; galactose; gas chromatography; headspace analysis; hexanoic acid; lactic acid; methanethiol; milk; nuclear magnetic resonance spectroscopy; odor compounds; odors; phenylacetic acid; solid phase microextraction; sucrose; sulfur; tandem mass spectrometry; ultra-performance liquid chromatography
Abstract:
... The whole sensometabolome of a typical dairy milk dessert was decoded to potentially serve as a blueprint for further flavor optimization steps of functional fat-reduced food. By applying the sensomics approach, a wide range of different dairy volatiles, semi and nonvolatiles, were analyzed by ultrahigh-performance liquid chromatography tandem mass spectrometry with or without derivatization prest ...
DOI:
10.1021/acs.jafc.1c02165

14. Simultaneous determination of N-methyl carbamate residues in pork tissues based on ultrasound assisted QuEChERS-dSPE extraction followed by reversed phase LC-FLD analysis

Author:
João F. Sousa; João N. Barros; Paulo Fernandes; Rosa Perestrelo; José S. Câmara
Source:
Lebensmittel-Wissenschaft + Technologie 2021 v.144 pp. 111199
ISSN:
0023-6438
Subject:
acetic acid; agitation; animals; cost effectiveness; derivatization; fluorescence; food safety; kidneys; liver; methylcarbamates; muscles; pork; reversed-phase high performance liquid chromatography; solid phase extraction; ultrasonics
Abstract:
... The presence of pesticide residues in animal tissues is a source of public awareness and health concerns. Therefore, to guarantee appropriate food safety and to enforce regulations, efficient, cost-effective and sensitive analytical methods are needed. This study set out to develop and validate a reliable and high-throughput analytical approach for the simultaneous determination of N-methyl carbam ...
DOI:
10.1016/j.lwt.2021.111199

15. A robust glycan labeling strategy using a new cationic hydrazide tag for MALDI-MS-based rapid and sensitive glycomics analysis

Author:
Yifang Zhang; Zhaoyu Hu; Chun Zhang; Bi-Feng Liu; Xin Liu
Source:
Talanta 2020 v.219 pp. 121356
ISSN:
0039-9140
Subject:
acetic acid; ambient temperature; blood serum; derivatization; glycomics; heat; hematologic tests; horses; humans; hydrazides; ions; polysaccharides; rapid methods; ribonucleases; sialic acid
Abstract:
... Chemical derivatization of glycans is a common strategy to increase the analytical performance of MALDI-MS-based glycan profiling techniques. Hydrazide, one of the most popular tags, offers important advantages including allowing purification-free procedures. Several hydrazides have thus been used for glycomics combined with an on-target strategy to further simplify the analytical procedures. Usua ...
DOI:
10.1016/j.talanta.2020.121356

16. A sensitive method for the determination of the gender difference of neuroactive metabolites in tryptophan and dopamine pathways in mouse serum and brain by UHPLC-MS/MS

Author:
Jiaxi Yao; Haihua Lu; Zhonghe Wang; Tingwei Wang; Fangfang Fang; Jun Wang; Jing Yu; Rong Gao
Source:
Journal of chromatography 2018 v.1093-1094 pp. 91-99
ISSN:
1570-0232
Subject:
acetic acid; blood serum; brain; chlorides; derivatization; dopamine; females; gender differences; high performance liquid chromatography; males; metabolites; mice; norepinephrine; organochlorine compounds; physiology; serotonin; solid phase extraction; tandem mass spectrometry; tryptophan; ultra-performance liquid chromatography
Abstract:
... Tryptophan (TRP) and dopamine (DA) pathways are of great importance for their related pathology and physiology. In the present study, a new reliable and sensitive analytical method was developed and validated for 12 neuroactive metabolites in TRP and DA pathways in mouse serum and brain by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS). The method ex ...
DOI:
10.1016/j.jchromb.2018.06.054

17. Analysis of inorganic cations and amino acids in high salinity samples by capillary electrophoresis and conductivity detection: Implications for in‐situ exploration of ocean worlds

Author:
Mauro Sergio Ferreira Santos; Thiago Gomes Cordeiro; Aaron C. Noell; Carlos D. Garcia; Maria F. Mora
Source:
Electrophoresis 2018 v.39 no.22 pp. 2890-2897
ISSN:
0173-0835
Subject:
acetic acid; amino acids; capillary electrophoresis; cations; derivatization; lakes; salinity; streams
Abstract:
... With growing interest in exploring ocean worlds, such as Europa and Enceladus, there is a fundamental need to develop liquid‐based analytical techniques capable of handling high salinity samples while performing both bulk and trace species measurements. In this context, CE with capacitively coupled contactless conductivity detection (CE–C⁴D) has tremendous potential. One of its advantages is that ...
DOI:
10.1002/elps.201800266

18. 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

19. 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

20. Development of a Single-Drop Microextraction with Derivatization Procedure for Analysis of Volatile Fatty Acids in Water Samples

Author:
Grażyna Wejnerowska
Source:
Chromatographia 2017 v.80 no.7 pp. 1115-1120
ISSN:
0009-5893
Subject:
acetic acid; derivatization; detection limit; flame ionization; ionic strength; microextraction; mixing; pH; solvents; temperature; volatile fatty acids
Abstract:
... A single-drop microextraction (SDME) was developed for the analysis of volatile fatty acids (VFAs) (C₂–C₇) in water by gas chromatography (GC) with flame ionization detection. The significant parameters affecting the SDME performance such as selection of microextraction solvent, extraction time, stirring rate, sample pH and temperature, and ionic strength were studied and optimized. To lower limit ...
DOI:
10.1007/s10337-017-3316-0
PubMed:
28725084
PubMed Central:
PMC5486468

21. Enantioselective analysis of bambuterol in human plasma using microwave‐assisted chiral derivatization coupled with ultra high performance liquid chromatography and tandem mass spectrometry

Author:
Ting Zhou; Jing Zeng; Ting Zhao; Qisheng Zhong; Yang Yang; Wen Tan
Source:
Journal of separation science 2017 v.40 no.13 pp. 2779-2790
ISSN:
1615-9306
Subject:
acetic acid; derivatization; drugs; enantiomers; enantioselectivity; humans; microwave radiation; microwave treatment; pharmacokinetics; tandem mass spectrometry; ultra-performance liquid chromatography
Abstract:
... In this study, an enantioselective analytical method based on microwave‐assisted chiral derivatization coupled with ultra high performance liquid chromatography and tandem mass spectrometry was developed for the determination of bambuterol enantiomers in human plasma. The chiral derivatization reaction was greatly accelerated by microwave irradiation. Under the optimized conditions, both the deriv ...
DOI:
10.1002/jssc.201700280

22. Simultaneous Analysis of 3-MCPD and 1,3-DCP in Asian Style Sauces Using QuEChERS Extraction and Gas Chromatography–Triple Quadrupole Mass Spectrometry

Author:
Genualdi Susan; Nyman Patricia; DeJager Lowri
Source:
Journal of agricultural and food chemistry 2017 v.65 no.4 pp. 981-985
ISSN:
1520-5118
Subject:
European Union; Food and Agriculture Organization; Food and Drug Administration; World Health Organization; acetic acid; alpha-chlorohydrin; carcinogens; catalysts; derivatization; detection limit; food additives; genotoxicity; hydrochloric acid; hydrolysis; manufacturing; markets; mass spectrometry; physicochemical properties; soy sauce; vegetable protein
Abstract:
... Acid hydrolyzed vegetable protein (aHVP) is used for flavoring a wide variety of foods and also in the production of nonfermented soy sauce. During the production of aHVP, chloropropanols including 3-monochloropropane-1,2-diol (3-MCPD) and 1,3 dichloropropane-2-ol (1,3-DCP) can be formed through the reaction of the hydrochloric acid catalyst and residual fat and the reaction of 3-MCPD with acetic ...
DOI:
10.1021/acs.jafc.6b05051
PubMed:
28064506
PubMed Central:
PMC5450852

23. The study and application of analyte adduct based ionisation of propofol in the analysis with liquid chromatography-tandem mass spectrometry

Author:
Marek Dziadosz
Source:
Journal of chromatography 2019 v.1114-1115 pp. 1-4
ISSN:
1570-0232
Subject:
acetates; acetic acid; ammonium acetate; calibration; derivatization; detection limit; ionization; ions; liquid chromatography; liquid-liquid extraction; methanol; monitoring; tandem mass spectrometry
Abstract:
... The ionisation of propofol was studied on the basis of analyte adduct formation with the components of the mobile phase. The identification of an appropriate propofol adduct ion generated in an acetate salt based buffer in the negative electrospray ionisation mode made the propofol LC-MS/MS analysis with two multiple reaction monitoring experiments possible without analyte derivatisation. Since a ...
DOI:
10.1016/j.jchromb.2019.03.018

24. Analysis of isophthalaldehyde in migration samples from polyethylene terephthalate packaging

Author:
Jazmín Osorio; Sara Úbeda; Margarita Aznar; Cristina Nerín
Source:
Food additives & contaminants 2018 v.35 no.8 pp. 1645-1652
ISSN:
1944-0057
Subject:
acetic acid; composite polymers; derivatization; detection limit; ethanol; food packaging; food-packaging materials; hydroxylamine; liquid-phase microextraction; polyethylene terephthalates; solid phase microextraction; statistical analysis; temperature
Abstract:
... In the present work, different pre-concentration strategies were evaluated for the analysis of isophthalaldehyde in migration samples from food packaging materials. This compound is a potential migrant in several copolymers used for food packaging, and since it is considered a non-intentionally added substance, its concentration in migration samples must be determined. Derivatisation was the first ...
DOI:
10.1080/19440049.2018.1465208

25. Analysis of thyreostats in bovine feces using ultra high performance liquid chromatography with tandem mass spectrometry

Author:
Sebastian Witek; Barbara Wozniak; Iwona Matraszek‐Zuchowska; Andrzej Posyniak
Source:
Journal of separation science 2018 v.41 no.5 pp. 1083-1090
ISSN:
1615-9306
Subject:
acetic acid; buffers; cattle; derivatization; feces; ionization; methanol; methylthiouracil; monitoring; pH; propylthiouracil; tandem mass spectrometry; thiouracil; ultra-performance liquid chromatography
Abstract:
... A method based on ultra‐high performance liquid chromatography was developed and validated to detect six thyreostatic compounds: tapazole, thiouracil, methylthiouracil, dimethylthiouracil, propylthiouracil, and phenylthiouracil in faeces of bovine. Thyreostats were extracted from the matrix with a mixture of methanol and buffer (pH = 8). Next step was derivatization of analytes with 3‐iodobenzylbr ...
DOI:
10.1002/jssc.201701069

26. Demonstration of hydrazide tagging for O-glycans and a central composite design of experiments optimization using the INLIGHT™ reagent

Author:
Samuel R. King; Elizabeth S. Hecht; David C. Muddiman
Source:
Analytical and bioanalytical chemistry 2018 v.410 no.5 pp. 1409-1415
ISSN:
1618-2642
Subject:
acetic acid; cattle; derivatization; experimental design; humans; hydrazides; immunoglobulin A; ionization; mucins; polysaccharides; surface area
Abstract:
... The INLIGHT™ strategy for N-linked glycan derivatization has been shown to overcome many of the challenges associated with glycan analysis. The hydrazide tag reacts efficiently with the glycans, increasing their non-polar surface area, allowing for reversed-phase separations and increased ionization efficiency. We have taken the INLIGHT™ strategy and adopted it for use with O-linked glycans. A cen ...
DOI:
10.1007/s00216-017-0828-2

27. Determination of Five Plant Growth Regulator Containing Carboxyl in Bean Sprouts Based on Chemical Derivatization by GC-MS

Author:
Guofu Qin; Keting Zou; Li Tian; Yongbo Li
Source:
Food analytical methods 2018 v.11 no.9 pp. 2628-2635
ISSN:
1936-9751
Subject:
4-CPA; acetic acid; bean sprouts; boron; crops; derivatization; detection limit; gas chromatography-mass spectrometry; indole acetic acid; indole butyric acid; methanol; statistical analysis
Abstract:
... An efficient and sensitive analytical method for the simultaneous determination of five plant growth regulators (PGRs) has been successfully developed, including 3-Indoleacetic acid (IAA), 2-Naphthylacetic acid (2-NAA), Beta-indolebutyric acid (IBA), 2-(2,4-dichlorophenoxy), acetic acid (2.4-D), and 4-Chlorophenoxyacetic acid (4-CPA) in bean sprouts. Using 10% boron trifluoride of methanol as the ...
DOI:
10.1007/s12161-018-1255-5

28. Direct determination of glyphosate, glufosinate, and AMPA in soybean and corn by liquid chromatography/tandem mass spectrometry

Author:
Narong Chamkasem; Tiffany Harmon
Source:
Analytical and bioanalytical chemistry 2016 v.408 no.18 pp. 4995-5004
ISSN:
1618-2642
Subject:
EDTA (chelating agent); acetic acid; anion exchange; cation exchange; corn; derivatization; detectors; fluorescence; glufosinate; glyphosate; isotope labeling; particulates; reversed-phase high performance liquid chromatography; soybeans; statistical analysis; tandem mass spectrometry
Abstract:
... Glyphosate, glufosinate, and aminomethylphosphonic acid (AMPA) are amphoteric, low mass, high water soluble, and do not have chromophore. They are very difficult to be retained on a reversed phase HPLC and detected by UV or fluorescence detectors. A liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed to determine these analytes in soybean and corn using a reversed phase ...
DOI:
10.1007/s00216-016-9597-6

29. Impact of Covalent Functionalization on the Aqueous Processability, Catalytic Activity, and Biocompatibility of Chemically Exfoliated MoS2 Nanosheets

Author:
Paredes Juan I.; Munuera José M.; Villar-Rodil Silvia; Guardia Laura; Ayán-Varela Miguel; Pagán Ana; Aznar-Cervantes Salvador D.; Cenis José L.; Martínez-Alonso Amelia; Tascón Juan M. D.
Source:
ACS Applied Materials & Interfaces 2016 v.8 no.41 pp. 27974-27986
ISSN:
1944-8252
Subject:
acetic acid; annealing; biocompatibility; catalytic activity; cell proliferation; derivatization; fibroblasts; mice; nanosheets; nanosilver
Abstract:
... Chemically exfoliated MoS₂ (ce-MoS₂) has emerged in recent years as an attractive two-dimensional material for use in relevant technological applications, but fully exploiting its potential and versatility will most probably require the deployment of appropriate chemical modification strategies. Here, we demonstrate that extensive covalent functionalization of ce-MoS₂ nanosheets with acetic acid g ...
DOI:
10.1021/acsami.6b08444

30. Selective non-chromatographic determination of tributyltin in sediments using EDTA and diphenylcarbazone as masking agent

Author:
Monika Truskolaska; Krzysztof Jankowski
Source:
International journal of environmental analytical chemistry 2018 v.98 no.4 pp. 295-307
ISSN:
1029-0397
Subject:
EDTA (chelating agent); acetic acid; aqueous solutions; atomic absorption spectrometry; chelates; chlorides; chromatography; coatings; derivatization; detection limit; dibutyltin; ethylation; freshwater; headspace analysis; hydrochloric acid; leaching; marine sediments; microwave treatment; monobutyltin; pH; sodium; solid phase microextraction; sorption; temperature; tin; tributyltin
Abstract:
... Two analytical procedures based on the generation of volatile tributyltin derivatives, their separation by headspace solid-phase microextraction (HS SPME) and subsequent determination using plasma optical emission spectrometry (OES) have been developed for the selective determination of trace tributyltin (TBT) in the presence of other butyltins and inorganic tin in sediments without the use of chr ...
DOI:
10.1080/03067319.2018.1456533

31. An efficient analytical method for determination of S-phenylmercapturic acid in urine by HPLC fluorimetric detector to assessing benzene exposure

Author:
Michele P. Rocha Mendes; Josianne Nicácio Silveira; Leiliane Coelho Andre
Source:
Journal of chromatography 2017 v.1063 pp. 136-140
ISSN:
1570-0232
Subject:
acetic acid; acetonitrile; air; alkaline hydrolysis; benzene; biomarkers; blood cells; byproducts; derivatization; detection limit; environmental exposure; fluorometry; high performance liquid chromatography; industry; nitrogen; petroleum; regression analysis; solid phase extraction; steel; urine
Abstract:
... Benzene is an important occupational and environmental contaminant, naturally present in petroleum and as by-product in the steel industry. Toxicological studies showed pronounced myelotoxic action, causing leukemic and others blood cells disorders. Assessing of benzene exposure is performed by biomarkers as trans, trans-muconic acid (AttM) and S-phenylmercapturic acid (S-PMA) in urine. Due to spe ...
DOI:
10.1016/j.jchromb.2017.07.039

32. Capillary electrophoresis fingerprinting of 8-aminopyrene-1,3,6-trisulfonate derivatized nitrocellulose after partial acid depolymerization

Author:
Elodie Alinat; Nathalie Delaunay; Cédric Przybylski; Régis Daniel; Xavier Archer; Pierre Gareil
Source:
Journal of chromatography 2015 v.1387 pp. 134-143
ISSN:
0021-9673
Subject:
acetic acid; capillary electrophoresis; chromatography; depolymerization; derivatization; electrolytes; forensic sciences; hydrochloric acid; matrix-assisted laser desorption-ionization mass spectrometry; methylcellulose; molecular weight; oligosaccharides; pH; proteins; reducing agents; solubility; temperature
Abstract:
... Fine characterization of nitrocellulose (NC) remains a challenge, especially in forensic analysis, and a strategy consisting in obtaining representative fingerprints by a separation technique, as for proteins, is of prime interest. In this work, we first established that NCs (especially of high molar mass) cannot be representatively derivatized by 8-aminopyrene-1,3,6-trisulfonic acid (APTS), becau ...
DOI:
10.1016/j.chroma.2015.01.092

33. Microwave-assisted deglycosylation for rapid and sensitive analysis of N-glycans via glycosylamine derivatization

Author:
Yike Wu; Chang Wang; Jing Luo; Yanyan Liu; Liang Zhang; Yun Xia; Xiaojun Feng; Bi-Feng Liu; Yawei Lin; Xin Liu
Source:
Analytical and bioanalytical chemistry 2017 v.409 no.16 pp. 4027-4036
ISSN:
1618-2642
Subject:
acetic acid; biomarkers; blood serum; cattle; derivatization; disease course; fetuins; glycoproteins; humans; lung neoplasms; matrix-assisted laser desorption-ionization mass spectrometry; microwave treatment; ovalbumin; polysaccharides; ribonucleases; t-test
Abstract:
... A rapid and sensitive N-glycan profiling strategy for MALDI-MS incorporating the use of deglycosylation with microwave assistance and the co-derivatization of glycosylamine labeling with tris(2,4,6-trimethoxyphenyl)phosphonium acetic acid N-hydroxysuccinimide ester (TMPP-Ac-OSu) and methylamidation has been developed in this work. Notably, highly efficient release and tagging of N-glycans from rib ...
DOI:
10.1007/s00216-017-0346-2

34. Release of toxic ammonia and volatile organic compounds by heated cannabis and their relation to tetrahydrocannabinol content

Author:
David Smith; Roger Bloor; Claire George; Andriy Pysanenko; Patrik Španěl
Source:
Analytical methods 2015 v.7 no.10 pp. 4104-4110
ISSN:
1759-9679
Subject:
acetates; acetic acid; active ingredients; adverse effects; air; ammonia; analgesia; breathing; buds; derivatization; gas chromatography-mass spectrometry; ingestion; leaves; methanol; molecular weight; monoterpenoids; polycyclic aromatic hydrocarbons; risk; sesquiterpenoids; smoke; tetrahydrocannabinol; toxic substances; toxicity; vapors; volatile organic compounds
Abstract:
... Studies have been carried out of the compounds generated from heated “street” cannabis in the commercial device known as the “Volcano” using the selected ion flow tube mass spectrometry (SIFT-MS) analytical method. Such vaporising devices are preferred for the delivery of the cannabis active ingredients for pain relief and therapeutic purposes since they remove from the smoke the harmful high mole ...
DOI:
10.1039/c5ay00593k

35. Simultaneous Cell Disruption Extraction and Purification Followed by Two-phase Derivatization Procedure for the Determination of Organotin Compounds in Wet Biological Samples by GC–MS

Author:
Chunzhao Chen; Ling Chen; Zhaoying Chen; Wen Zhang; Lingling Wu; Qinghui Huang
Source:
Chromatographia 2017 v.80 no.11 pp. 1659-1667
ISSN:
0009-5893
Subject:
acetic acid; adsorption; cell membranes; centrifugation; cities; derivatization; detection limit; dibutyltin; ethyl acetate; freeze drying; gas chromatography-mass spectrometry; methanol; oysters; solvents; statistical analysis; tin; tissues; tributyltin; tropolone; ultrasonics; China
Abstract:
... Freeze-dried biological samples used for the determination of organotin compounds (OTCs) involve complicated or tedious pretreatment (e.g., freeze-drying) that may result in loss of analyst or contamination. In the present study, a rapid and accurate method for determination of five kinds of OTCs—monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPhT) and triphenyltin (TPhT) in ...
DOI:
10.1007/s10337-017-3399-7

36. Unifying bacteria from decaying wood with various ubiquitous Gibbsiella species as G. acetica sp. nov. based on nucleotide sequence similarities and their acetic acid secretion

Author:
Klaus Geider; Marina Gernold; Susanne Jock; Annette Wensing; Beate Völksch; Jürgen Gross; Dieter Spiteller
Source:
Microbiological research 2015 v.181 pp. 93-104
ISSN:
0944-5013
Subject:
DNA primers; Enterobacteriaceae; Malus domestica; Pyrus communis; Quercus; acetic acid; apples; bacteria; calcium carbonate; dead wood; derivatization; essential genes; gas chromatography-mass spectrometry; levan; levansucrase; new species; nuclear magnetic resonance spectroscopy; nucleotide sequences; pears; phenotype; polymerase chain reaction; proline; pulsed-field gel electrophoresis; ribosomal RNA; screening; secretion; sequence homology; trees; wood; Austria; China; Germany; Japan; Korean Peninsula; Spain; United Kingdom
Abstract:
... Bacteria were isolated from necrotic apple and pear tree tissue and from dead wood in Germany and Austria as well as from pear tree exudate in China. They were selected for growth at 37°C, screened for levan production and then characterized as Gram-negative, facultatively anaerobic rods. Nucleotide sequences from 16S rRNA genes, the housekeeping genes dnaJ, gyrB, recA and rpoB alignments, BLAST s ...
DOI:
10.1016/j.micres.2015.05.003

37. A fully automated effervescence assisted dispersive liquid–liquid microextraction based on a stepwise injection system. Determination of antipyrine in saliva samples

Author:
Kseniia Medinskaia; Christina Vakh; Darina Aseeva; Vasil Andruch; Leonid Moskvin; Andrey Bulatov
Source:
Analytica chimica acta 2016 v.902 pp. 129-134
ISSN:
0003-2670
Subject:
absorbance; acetic acid; analytical chemistry; antipyrine; carbon dioxide; centrifugation; derivatization; liquid-phase microextraction; methylene chloride; microbubbles; nitrogen; saliva; separation; sodium carbonate; solvents; streams; wavelengths
Abstract:
... A first attempt to automate the effervescence assisted dispersive liquid–liquid microextraction (EA-DLLME) has been reported. The method is based on the aspiration of a sample and all required aqueous reagents into the stepwise injection analysis (SWIA) manifold, followed by simultaneous counterflow injection of the extraction solvent (dichloromethane), the mixture of the effervescence agent (0.5  ...
DOI:
10.1016/j.aca.2015.11.017

38. A versatile method for analysis of saliva, plasma and urine for total thiols using HPLC with UV detection

Author:
Justyna Stachniuk; Paweł Kubalczyk; Paulina Furmaniak; Rafał Głowacki
Source:
Talanta 2016 v.155 pp. 70-77
ISSN:
0039-9140
Subject:
acetic acid; acetylcysteine; cysteine; derivatization; ethanol; glutathione; high performance liquid chromatography; homocysteine; humans; patients; saliva; thiols; urine
Abstract:
... A simple and rapid HPLC method using 2-chloro-1-methyllepidinium tetrafluoroborate (CMLT) as a derivatization reagent was developed for simultaneous determination of homocysteine (Hcy), glutathione (GSH), γ-glutamylcysteine (γ-GluCys), cysteinylglycine (CysGly), N-acetylcysteine (NACys) and cysteine (Cys) in human saliva, plasma and urine. Separation of the analytes was achieved in just 7min using ...
DOI:
10.1016/j.talanta.2016.04.031

39. An integrated liquid chromatography–tandem mass spectrometry approach for the ultra-sensitive determination of catecholamines in human peripheral blood mononuclear cells to assess neural-immune communication

Author:
Xiaoguang (Sunny) Li; Shu Li; Gottfried Kellermann
Source:
Journal of chromatography 2016 v.1449 pp. 54-61
ISSN:
0021-9673
Subject:
acetic acid; density gradient centrifugation; derivatization; dopamine; epinephrine; evaporation; formic acid; humans; liquid chromatography; metabolites; mononuclear leukocytes; nervous system diseases; norepinephrine; solid phase extraction; tandem mass spectrometry
Abstract:
... Catecholamines play a vital role in the interactions between the nervous and immune systems and their dysfunctions are implicated in various autoimmune and neurological diseases. However, accurate quantitation of catecholamines in the immune system presents a special analytical challenge. We proposed the first LC–MS/MS method for the determination of catecholamines in human peripheral blood mononu ...
DOI:
10.1016/j.chroma.2016.04.039

40. Determination of methacrylic acid in food simulants by pyrolytic butylation-gas chromatography

Author:
Zhongping Huang; Ruofeng Qiu; Tingfei Liu; Yilei Huang; Zuoyi Zhu; Lili Wang
Source:
Journal of chromatography 2016 v.1454 pp. 101-106
ISSN:
0021-9673
Subject:
acetic acid; butylation; derivatization; detection limit; ethanol; gas chromatography; iso-octanes; rapid methods; statistical analysis; temperature; tetrabutylammonium compounds
Abstract:
... An on-line pyrolytic butylation approach was proposed to determine methacrylic acid (MA) in food simulants by gas chromatography (GC) without an expensive pyrolyzer. MA in food simulants was converted into butyl methacrylate in the presence of tetrabutylammonium hydroxide (TBAH) without any pretreatment at 330°C in the injection-port, contributing to high GC signal response. The derivatizing condi ...
DOI:
10.1016/j.chroma.2016.05.068

41. Development, validation and biomedical applications of stable-isotope dilution GC–MS and GC–MS/MS techniques for circulating malondialdehyde (MDA) after pentafluorobenzyl bromide derivatization: MDA as a biomarker of oxidative stress and its relation to 15(S)-8-iso-prostaglandin F2α and nitric oxide (NO)

Author:
Dimitrios Tsikas; Sabine Rothmann; Jessica Y. Schneider; Maria-Theresia Suchy; Arne Trettin; Darko Modun; Nadine Stuke; Norbert Maassen; Jürgen C. Frölich
Source:
Journal of chromatography 2016 v.1019 pp. 95-111
ISSN:
1570-0232
Subject:
EDTA (chelating agent); absorbance; acetic acid; acetone; acidity; anions; anticoagulants; aqueous solutions; biomarkers; blood sampling; blood serum; carbonyl compounds; clinical trials; derivatization; fluorescence; gas chromatography-mass spectrometry; high performance liquid chromatography; humans; ionization; lipid peroxidation; malondialdehyde; molecular weight; monitoring; nitric oxide; oxidative stress; protons; quantitative analysis; solvents; stable isotopes; thiobarbituric acid; thiobarbituric acid-reactive substances; toluene
Abstract:
... Malondialdehyde (MDA, CH2(CHO)2) is one of the best investigated and most frequently measured biomarkers of lipid peroxidation in biological fluids, a constituent of the so called thiobarbituric acid reactive substances (TBARS). The reaction of thiobarbituric acid with MDA and other carbonyl compounds is the basis for the batch TBARS assay, one of the most commonly and widely used assays of oxidat ...
DOI:
10.1016/j.jchromb.2015.10.009

42. Identification and Anti‐oxidant Capacity Determination of Phenolics and their Glycosides in Elderflower by On‐line HPLC–CUPRAC Method

Author:
S. Esin Çelik; Mustafa Özyürek; Kubilay Güçlü; Esra Çapanoğlu; Reşat Apak
Source:
Phytochemical analysis 2014 v.25 no.2 pp. 147-154
ISSN:
0958-0344
Subject:
Sambucus nigra; absorption; acetic acid; copper; derivatization; detection limit; glucose; glycosides; high performance liquid chromatography; kaempferol; polyphenols; quercetin; rhamnose
Abstract:
... INTRODUCTION: Development and application of an on‐line cupric reducing anti‐oxidant capacity (CUPRAC) assay coupled with HPLC for separation and on‐line determination of phenolic anti‐oxidants in elderflower (Sambucus nigra L.) extracts for their anti‐oxidant capacity are significant for evaluating health‐beneficial effects. Moreover, this work aimed to assay certain flavonoid glycosides of elder ...
DOI:
10.1002/pca.2481
PubMed:
24408862

43. Simultaneous determination of aliphatic, aromatic and heterocyclic biogenic amines without derivatization by capillary electrophoresis and application in beer analysis

Author:
Lili He; Zhongqi Xu; Takeshi Hirokawa; Li Shen
Source:
Journal of chromatography 2016 pp. -
ISSN:
0021-9673
Subject:
acetic acid; alpha-cyclodextrin; aromatic amines; beers; biogenic amines; capillary electrophoresis; carnosine; chromatography; derivatization; electrolytes; food quality; health foods; human health; pH; wavelengths
Abstract:
... Biogenic amines (BAs) play significant roles in indicating human health or food quality. Aiming to simultaneously determine three structures (aliphatic, aromatic and heterocyclic) of underivatized BAs, we explored a simple and rapid capillary electrophoresis (CE) method only coupled with conventional UV detector for the separation of thirteen key BAs. The strategy is to choose a UV absorbing probe ...
DOI:
10.1016/j.chroma.2016.12.067

44. Critical development by design of a rugged HPLC-MS/MS method for direct determination of ibuprofen enantiomers in human plasma

Author:
Natalija Nakov; Rumenka Petkovska; Liljana Ugrinova; Zoran Kavrakovski; Aneta Dimitrovska; Dobrin Svinarov
Source:
Journal of Chromatography B 2015 v.992 pp. 67-75
ISSN:
1570-0232
Subject:
acetic acid; cellulose; chromatography; derivatization; detection limit; enantiomers; experimental design; guidelines; humans; ibuprofen; ketoprofen; methanol; oral administration; pH; solvents; temperature
Abstract:
... Development and validation of a HPLC-MS/MS method for direct determination of R- and S-ibuprofen (Ibu) in human plasma without a need of derivatization or other complexities such as postcolumn infusion of solvents or reagents was performed. Critical steps were investigated during method development using experimental design to achieve a reliable and rugged assay. The LC-MS/MS separation of R-Ibu a ...
DOI:
10.1016/j.jchromb.2015.04.029

45. Determination of molecular weight distributions in native and pretreated wood

Author:
Timo Leskinen; Stephen S. Kelley; Dimitris S. Argyropoulos
Source:
Carbohydrate polymers 2015 v.119 pp. 44-52
ISSN:
0144-8617
Subject:
acetic acid; biorefining; carbohydrates; chemical treatment; derivatization; gel chromatography; ionic liquids; lignin; milling; molecular weight; oxidation; pulping; saccharification; sawdust; softwood; solubilization
Abstract:
... The analysis of native wood components by size-exclusion chromatography (SEC) is challenging. Isolation, derivatization and solubilization of wood polymers is required prior to the analysis. The present approach allowed the determination of molecular weight distributions of the carbohydrates and of lignin in native and processed woods, without preparative component isolation steps. For the first t ...
DOI:
10.1016/j.carbpol.2014.11.026

46. Luminescent determination of quinolones in milk samples by liquid chromatography/post-column derivatization with terbium oxide nanoparticles

Author:
G.S. Yánez-Jácome; M.P. Aguilar-Caballos; A. Gómez-Hens
Source:
Journal of chromatography 2015 v.1405 pp. 126-132
ISSN:
0021-9673
Subject:
acetic acid; acetonitrile; antibiotics; calibration; chelates; ciprofloxacin; danofloxacin; derivatization; detection limit; enrofloxacin; flumequine; graphs; liquid chromatography; liquids; luminescence; marbofloxacin; methanol; models; nanoparticles; oxolinic acid; sarafloxacin; statistical analysis; terbium; whole milk
Abstract:
... The usefulness of terbium oxide nanoparticles (Tb4O7NPs) as post-column derivatizing reagent for the liquid chromatographic determination of residues of quinolone antibiotics in milk samples has been studied. Seven quinolones of veterinary use have been chosen as model analytes to develop this method. The derivatization step is based on the formation of luminescent chelates of quinolones with Tb4O ...
DOI:
10.1016/j.chroma.2015.05.070

47. Matrix solid phase dispersion assisted enzymatic hydrolysis as a novel approach for cocaine and opiates isolation from human hair

Author:
Martha Míguez-Framil; Pamela Cabarcos; María Jesús Tabernero; Ana María Bermejo; Pilar Bermejo-Barrera; Antonio Moreda-Piñeiro
Source:
Journal of chromatography 2013 v.1316 no. pp. 15-22
ISSN:
0021-9673
Subject:
Food and Drug Administration; acetic acid; aluminum oxide; cocaine; codeine; derivatization; enzymatic hydrolysis; evaporation; gas chromatography-mass spectrometry; humans; hydrochloric acid; illicit drugs; methanol; mixing; morphine; nitrogen; pH; screening; solid phase extraction; United States
Abstract:
... The possibility of assisting enzymatic hydrolysis (EH) procedures by sample disruption mechanisms inherent to matrix solid phase dispersion (MSPD) has been explored in the current study. EH of hair specimens from poly-drug abusers was assisted by dispersing/blending the sample (0.05g) with alumina (2.25g) before loading the dissolved enzyme (6mL of 1mgmL⁻¹ Pronase E in 1.4M/1.4M Tris/HCl, pH 7.3) ...
DOI:
10.1016/j.chroma.2013.09.063

48. Mineralization of paracetamol in aqueous solution with advanced oxidation processes

Author:
Murat Torun; Özge Gültekin; Dilek Şolpan; Olgun Güven
Source:
Environmental technology 2015 v.36 no.8 pp. 970-982
ISSN:
1479-487X
Subject:
acetaminophen; acetic acid; aquatic environment; aqueous solutions; derivatization; dissolved oxygen; environmental technology; formic acid; free radicals; gamma radiation; gas chromatography; humans; hydroquinone; inorganic ions; ion exchange chromatography; irradiation; mass spectrometry; mineralization; nitrates; nitrites; oxalic acid; oxidation; oxygen consumption; ozonation; ozone; pH; persistent organic pollutants; synergism; toxicity; yields
Abstract:
... Paracetamol is a common analgesic drug widely used in all regions of the world more than hundred tonnes per year and it poses a great problem for the aquatic environment. Its phenolic intermediates are classified as persistent organic pollutants and toxic for the environment as well as human beings. In the present study, the irradiation of aqueous solutions of paracetamol with ⁶⁰Co gamma-rays was ...
DOI:
10.1080/09593330.2014.970585

49. Total water-soluble sugars quantification in bio-oil using the phenol–sulfuric acid assay

Author:
Marjorie R. Rover; Patrick A. Johnston; Buddhi P. Lamsal; Robert C. Brown
Source:
Journal of analytical and applied pyrolysis 2013 v.104 no. pp. 194-201
ISSN:
0165-2370
Subject:
acetic acid; biofuels; biomass; cellulose; derivatization; formic acid; fructose; fucose; furfural; furfuryl alcohol; galactose; gas chromatography-mass spectrometry; glucose; glycolic acid; high performance liquid chromatography; hydrolysis; hydroxymethylfurfural; ion exchange chromatography; mannose; nuclear magnetic resonance spectroscopy; phenol; propionic acid; pyrolysis; solvents; uncertainty; water solubility
Abstract:
... Bio-oil produced from fast pyrolysis of biomass contains sugars originating from cellulose. Traditional quantification of sugars in bio-oil is accomplished by gas chromatography/mass spectroscopy (GC/MS) via derivatization, high performance liquid chromatography (HPLC), ion chromatography (IC), or nuclear magnetic resonance (NMR) methodologies. These techniques are highly specific for each sugar, ...
DOI:
10.1016/j.jaap.2013.08.004

50. A Fast and Validated Method for the Determination of Malondialdehyde in Fish Liver Using High‐Performance Liquid Chromatography with a Photodiode Array Detector

Author:
Mohammad Faizan; Tuba Esatbeyoglu; Banu Bayram; Gerald Rimbach
Source:
Journal of food science 2014 v.79 no.4 pp. C484
ISSN:
0022-1147
Subject:
Food and Drug Administration; acetic acid; derivatization; detection limit; fish; high performance liquid chromatography; lipid peroxidation; liver; malondialdehyde; United States
Abstract:
... Malondialdehyde (MDA) is a biomarker of lipid peroxidation and is present in foods and biological samples such as plasma. A high‐performance liquid chromatography (HPLC) method was applied to determine MDA in fish liver samples after derivatization with 2,4‐dinitrophenylhydrazine (DNPH) using a ODS2 column (10 cm × 4.6 mm, 3 μm) and a photodiode array detector. The mobile phase consisted of 0.2% a ...
DOI:
10.1111/1750-3841.12412
PubMed:
24621264

51. A high-performance liquid chromatography method with pre-column derivatization for the simultaneous determination of reduced glutathione, carnosine and taurine

Author:
Maria A. Khalikova; Dalibor Satinsky; Petr Solich; Alexandr A. Zinchenko; Elena T. Zhilyakova; Oleg O. Novikov
Source:
Analytical methods 2014 v.6 no.5 pp. 1475-1481
ISSN:
1759-9679
Subject:
acetic acid; acetonitrile; aqueous solutions; carnosine; derivatization; glutathione; pH; reversed-phase high performance liquid chromatography; taurine; temperature; triethylamine; wavelengths
Abstract:
... A new gradient reversed-phase HPLC method with pre-column derivatization was developed and validated for simultaneous determination of reduced glutathione, carnosine and taurine in new pharmaceutical eye drops. Chromatographic separation was achieved with a fused core analytical column Supelco Ascentis Express C18 (100 mm × 4.6 mm, 2.7 μm). A 30 mM triethylamine in acetonitrile with 30 mM triethyl ...
DOI:
10.1039/c3ay42200c

52. Accurate and Reproducible Determination of Lignin Molar Mass by Acetobromination

Author:
Asikkala Janne; Tamminen Tarja; Argyropoulos Dimitris S.
Source:
Journal of agricultural and food chemistry 2012 v.60 no.36 pp. 8968-8973
ISSN:
1520-5118
Subject:
acetic acid; derivatization; bromine; softwood; gel chromatography; acetylation; temperature; molecular weight; lignin; solubilization
Abstract:
... The accurate and reproducible determination of lignin molar mass by using size exclusion chromatography (SEC) is challenging. The lignin association effects, known to dominate underivatized lignins, have been thoroughly addressed by reaction with acetyl bromide in an excess of glacial acetic acid. The combination of a concerted acetylation with the introduction of bromine within the lignin alkyl s ...
DOI:
10.1021/jf303003d
PubMed:
22870925

53. Catalytic acetoxylation of lactic acid to 2-acetoxypropionic acid, en route to acrylic acid

Author:
Rolf Beerthuis; Marta Granollers; D. Robert Brown; Horacio J. Salavagione; Gadi Rothenberg; N. Raveendran Shiju
Source:
RSC advances 2014 v.5 no.6 pp. 4103-4108
ISSN:
2046-2069
Subject:
acetic acid; acrylic acid; catalysts; catalytic activity; derivatization; gas chromatography; graphene; ion exchange; ion exchange resins; lactic acid; pyrolysis; quantitative analysis; silica gel; silylation; solvents; zeolites; zirconium oxide
Abstract:
... We present an alternative synthetic route to acrylic acid, starting from the platform chemical lactic acid and using heterogeneous catalysis. To improve selectivity, we designed an indirect dehydration reaction that proceeds via acetoxylation of lactic acid to 2-acetoxypropionic acid. This intermediate can then be pyrolized to acrylic acid. Acetic acid is used both as a reagent and a solvent in th ...
DOI:
10.1039/c4ra12695e

54. Cationic labeling of oligosaccharides for electrophoretic preconcentration and separation with contactless conductivity detection

Author:
Jan Partyka; Frantisek Foret
Source:
Journal of chromatography 2012 v.1267 no. pp. 116-120
ISSN:
0021-9673
Subject:
acetic acid; ammonium acetate; capillary electrophoresis; chromatography; derivatization; detection limit; dextran; electrolytes; hydrolysis; ionization; mass spectrometry; oligosaccharides
Abstract:
... Cationic derivatization of oligosaccharides by quaternary ammonium label was investigated for capillary electrophoretic separation with transient isotachophoretic preconcentration (t-ITP) as detected by capacitively coupled contactless conductivity detection (C4D). Dextran ladder, prepared by partial hydrolysis of dextran, isomaltotriose, maltopentaose and maltoheptaose were derivatized by reducti ...
DOI:
10.1016/j.chroma.2012.06.044

55. Determination of sialic acids in immune system cells (coelomocytes) of sea urchin, Paracentrotus lividus, using capillary LC-ESI-MS/MS

Author:
Savaş İzzetoğlu; Umut Şahar; Ecem Şener; Remziye Deveci
Source:
Fish & shellfish immunology 2014 v.36 no.1 pp. 181-186
ISSN:
1050-4648
Subject:
Paracentrotus lividus; acetic acid; anti-infective agents; cattle; cytotoxicity; derivatization; encapsulation; immune response; immune system; mucins; phagocytosis; sialic acids; tandem mass spectrometry
Abstract:
... Coelomocytes are considered to be immune effectors of sea urchins. Coelomocytes are the freely circulating cells in the body fluid contained in echinoderm coelom and mediate the cellular defence responses to immune challenges by phagocytosis, encapsulation, cytotoxicity and the production of antimicrobial agents. Coelomocytes have the ability to recognize self from non-self. Considering that siali ...
DOI:
10.1016/j.fsi.2013.10.029
PubMed:
24215912
PubMed Central:
PMC7111654

56. HPLC–DAD–FLD Determination of Veterinary Pharmaceuticals in Pharmaceutical Industry Wastewater with Precolumn Derivatization Using Fluorescamine

Author:
Danijela Ašperger; Vesna Tišler; Mirta Zrnčić; Dragana Mutavdžić Pavlović; Sandra Babić; Alka J. M. Horvat; Marija Kaštelan-Macan
Source:
Chromatographia 2014 v.77 no.15-16 pp. 1059-1066
ISSN:
0009-5893
Subject:
acetic acid; acetonitrile; anesthetics; antibiotics; ciprofloxacin; cleaning; derivatization; detectors; enrofloxacin; fluorescence; liquid chromatography; norfloxacin; pharmaceutical industry; procaine; solid phase extraction; sulfadiazine; veterinary drugs; wastewater
Abstract:
... A simple and robust method suitable for routine analysis of pharmaceuticals from different classes in pharmaceutical industry wastewater samples is presented. Seven veterinary pharmaceuticals (antibiotics and anesthetic) were simultaneously isolated from a highly complex wastewater matrix. Target compounds were three sulfonamide antibiotics (sulfaguanidine, sulfadiazine, and sulfamethazine), three ...
DOI:
10.1007/s10337-014-2685-x

57. Optimisation of a sample preparation method for the determination of fumonisin B1 in rice

Author:
Mateus Henrique Petrarca; Maria Isabel Rodrigues; Elizeu Antonio Rossi; Célia Maria de Sylos
Source:
Food chemistry 2014 v.158 pp. 270-277
ISSN:
0308-8146
Subject:
acetic acid; acetonitrile; aqueous solutions; cost effectiveness; derivatization; detection limit; diatomaceous earth; experimental design; fumonisin B1; rice; sodium chloride; sodium sulfate; Brazil
Abstract:
... A simple, rapid and cost-effective sample preparation method for the determination of fumonisin B1 in rice was optimised using a strategy of sequential experimental designs. Initially, a Plackett–Burman design was applied to select the statistically significant variables for the determination of fumonisin B1, and then, a central composite rotatable design was used to define the optimal conditions ...
DOI:
10.1016/j.foodchem.2014.02.126

58. Preparation and odour properties of the four stereoisomers of 2‐hexyl‐4‐acetoxytetrahydrofuran

Author:
Guoying Zhang; Xiuqin Gong; Shaoxiang Yang; Baoguo Sun; Yongguo Liu; Hongyu Tian
Source:
Flavour and fragrance journal 2014 v.29 no.4 pp. 249-254
ISSN:
0882-5734
Subject:
acetic acid; derivatization; enantiomers; Pseudozyma antarctica; cis-trans isomers; acetic anhydride; dihydroxylation; high performance liquid chromatography; oxidants; acylation; hydrolysis; odors; nitrobenzoic acids; alcohols
Abstract:
... The four stereoisomers of 2‐hexyl‐4‐acetoxytetrahydrofuran were prepared starting from (R)‐ or (S)‐1‐decen‐4‐ol (>96% ee). They were obtained by kinetic resolution of racemic homoallylic alcohol catalysed by Novozym 435 (Candida antarctica). (R)‐ or (S)‐1‐Decen‐4‐ol proceeded Sharpless asymmetric dihydroxylation (AD) using AD‐mix‐α or β as an oxidant followed by ring closure to afford cis‐2‐hexyl‐ ...
DOI:
10.1002/ffj.3202

59. Quantitative determination of seven chemical constituents and chemo‐type differentiation of chamomiles using high‐performance thin‐layer chromatography

Author:
Satyanarayanaraju Sagi; Bharathi Avula; Yan‐Hong Wang; Jianping Zhao; Ikhlas A. Khan
Source:
Journal of separation science 2014 v.37 no.19 pp. 2797-2804
ISSN:
1615-9306
Subject:
derivatization; formic acid; glucosides; coumarin; computer software; thin layer chromatography; dietary supplements; separation; detection limit; Chrysanthemum; absorbance; methylene chloride; luteolin; rutin; silica; densitometry; quantitative analysis; chamomile; principal component analysis; acetonitrile; chemical composition; acetic acid; absorption; umbelliferones; precision; apigenin
Abstract:
... A simple and rapid high‐performance thin‐layer chromatographic method was developed for the separation and determination of six flavonoids (rutin, luteolin‐7‐O‐β‐glucoside, chamaemeloside, apigenin‐7‐O‐β‐glucoside, luteolin, apigenin) and one coumarin, umbelliferone from chamomile plant samples and dietary supplements. The separation was achieved on amino silica stationary phase using dichlorometh ...
Handle:
10113/62280
DOI:
10.1002/jssc.201400646
PubMed:
25073627

60. Rapid analysis of aflatoxins B₁, B₂, and ochratoxin A in rice samples using dispersive liquid–liquid microextraction combined with HPLC

Author:
Xian‐Wen Lai; Dai‐Li Sun; Chun‐Qiang Ruan; He Zhang; Cheng‐Lan Liu
Source:
Journal of separation science 2014 v.37 no.1-2 pp. 92-98
ISSN:
1615-9306
Subject:
acetic acid; aflatoxins; chloroform; derivatization; detection limit; fluorescence; high performance liquid chromatography; liquid-liquid extraction; microextraction; ochratoxin A; pH; rapid methods; rice; supermarkets; China
Abstract:
... A novel, simple, and rapid method is presented for the analysis of aflatoxin B₁, aflatoxin B₂, and ochratoxin A in rice samples by dispersive liquid–liquid microextraction combined with LC and fluorescence detection. After extraction of the rice samples with a mixture of acetonitrile/water/acetic acid, mycotoxins were rapidly partitioned into a small volume of organic solvent (chloroform) by dispe ...
DOI:
10.1002/jssc.201300970

61. Vortex‐assisted surfactant‐enhanced‐emulsification liquid–liquid microextraction of biogenic amines in fermented foods before their simultaneous analysis by high‐performance liquid chromatography

Author:
Jaruwan Donthuan; Sirinda Yunchalard; Supalax Srijaranai
Source:
Journal of separation science 2014 v.37 no.21 pp. 3164-3173
ISSN:
1615-9306
Subject:
acetic acid; acetonitrile; beers; cadaverine; derivatization; detection limit; emulsifying; fermented fish; food contamination; high performance liquid chromatography; histamine; microextraction; spermidine; tryptamine; tyramine; wines
Abstract:
... A simple, rapid, sensitive, and environmentally friendly method, based on modified dispersive liquid–liquid microextraction coupled with high‐performance liquid chromatography was developed for the simultaneous determination of five biogenic amines in fermented food samples. Biogenic amines were derivatized with 9‐fluorenylmethyl chloroformate, extracted by vortex‐assisted surfactant‐enhanced emul ...
DOI:
10.1002/jssc.201400570
PubMed:
25142110

62. 11-Nor-9-carboxy-∆9-tetrahydrocannabinol quantification in human oral fluid by liquid chromatography–tandem mass spectrometry

Author:
Karl B. Scheidweiler; Sarah K. Himes; Xiaohong Chen; Hua-Fen Liu; Marilyn A. Huestis
Source:
Analytical and bioanalytical chemistry 2013 v.405 no.18 pp. 6019-6027
ISSN:
1618-2642
Subject:
Cannabis; acetic acid; cannabinoids; derivatization; drug therapy; drugs; humans; ionization; liquid chromatography; methanol; monitoring; pain; quality control; solid phase extraction; tandem mass spectrometry; working conditions
Abstract:
... Currently, ∆9-tetrahydrocannabinol (THC) is the analyte quantified for oral fluid cannabinoid monitoring. The potential for false-positive oral fluid cannabinoid results from passive exposure to THC-laden cannabis smoke raises concerns for this promising new monitoring technology. Oral fluid 11-nor-9-carboxy-∆9-tetrahydrocannabinol (THCCOOH) is proposed as a marker of cannabis intake since it is n ...
DOI:
10.1007/s00216-013-7027-6
PubMed:
23681203
PubMed Central:
PMC3773502

63. A new high-performance thin layer chromatography-based assay of detergents and surfactants commonly used in membrane protein studies

Author:
Laurie-Anne Barret; Ange Polidori; Françoise Bonneté; Pierre Bernard-Savary; Colette Jungas
Source:
Journal of chromatography 2013 v.1281 no. pp. 135-141
ISSN:
0021-9673
Subject:
acetic acid; buffers; crystallization; crystallography; derivatization; detection limit; detergents; hydrophobicity; membrane proteins; methanol; methylene chloride; sodium chloride; solubilization; surfactants; thin layer chromatography
Abstract:
... The hydrophobic nature of membrane proteins (MPs) necessitates the use of detergents for their extraction, solubilization and purification. Because the concentration of amphiphiles is crucial in the crystallization process, detergent quantification is essential to routine analysis. Here we describe a quantitative high-performance thin-layer chromatography (HPTLC) method we developed for the detect ...
DOI:
10.1016/j.chroma.2013.01.061

64. Analytical method for the simultaneous determination of polyfunctional amines used as monomers in the manufacture of food packaging materials

Author:
R. Paseiro-Cerrato; A. Rodríguez-Bernaldo de Quirós; Raquel Sendón; Juana Bustos; E. Ruíz; J.M. Cruz; P. Paseiro-Losada
Source:
Journal of chromatography 2011 v.1218 no.40 pp. 7105-7109
ISSN:
0021-9673
Subject:
acetic acid; amines; derivatization; detection limit; ethanol; food packaging; high performance liquid chromatography; manufacturing; olive oil; packaging materials
Abstract:
... This paper describes the development of a multi-analyte method for the determination of polyfunctional amines commonly used as monomers in the manufacture of food contact materials. Amines were analyzed by high-performance-liquid chromatography with diode-array detection (HPLC-DAD) after derivatization with dansyl chloride. The chromatographic analysis and the derivatization conditions were optimi ...
DOI:
10.1016/j.chroma.2011.07.068

65. Capillary electrophoresis with contactless conductivity detection for the determination of carnitine and acylcarnitines in clinical samples

Author:
Worapan Pormsila; Réjane Morand; Stephan Krähenbühl; Peter C. Hauser
Source:
Journal of chromatography 2011 v.879 no.13-14 pp. 921-926
ISSN:
1570-0232
Subject:
acetic acid; capillary electrophoresis; carnitine; chromatography; correlation; derivatization; detection limit; pH; patients; therapeutics; urine
Abstract:
... A capillary electrophoresis method with contactless conductivity detection was developed for the quantification of carnitine and six acylcarnitines in plasma and urine samples. The running buffer employed consisted of 500mmol/L acetic acid, 1.0mmol/L hydroxypropyl-β-cyclodextrin and 0.05% Tween at a pH of 2.6. Under these conditions, the isomeric valproyl- and octanoyl-carnitines could be distingu ...
DOI:
10.1016/j.jchromb.2011.02.046

66. Determination of fatty alcohol ethoxylates and alkylether sulfates by anionic exchange separation, derivatization with a cyclic anhydride and liquid chromatography

Author:
M. Beneito-Cambra; L. Ripoll-Seguer; J.M. Herrero-Martínez; E.F. Simó-Alfonso; G. Ramis-Ramos
Source:
Journal of chromatography 2011 v.1218 no.47 pp. 8511-8518
ISSN:
0021-9673
Subject:
acetic acid; acetonitrile; anhydrides; cations; cross contamination; derivatization; esterification; hydrochloric acid; hydrophobicity; liquid chromatography; methanol; seawater; solid phase extraction; sulfates; surfactants; transesterification; washing
Abstract:
... A method for the separation, characterization and determination of fatty alcohol ethoxylates (FAE) and alkylether sulfates (AES) in industrial and environmental samples is described. Separation of the two surfactant classes was achieved in a 50:50 methanol–water medium by retaining AES on a strong anionic exchanger (SAX) whereas most FAE were eluted. After washing the SAX cartridges to remove cati ...
DOI:
10.1016/j.chroma.2011.09.059

67. Determination of macrocyclic lactones in food and feed

Author:
Roberta Galarini; Giorgio Saluti; Simone Moretti; Danilo Giusepponi; Guglielmo Dusi
Source:
Food additives & contaminants 2013 v.30 no.6 pp. 1068-1079
ISSN:
1944-0057
Subject:
abamectin; acetic acid; derivatization; doramectin; eprinomectin; fluorescence; foods; high performance liquid chromatography; ivermectin; liver; milk; moxidectin; veterinary drugs
Abstract:
... A confirmatory high-performance liquid chromatography method with fluorescence detection (HPLC-FLD) was developed and validated for the simultaneous determination of the following anti-parasitic veterinary drugs in foodstuffs (liver, muscle and milk) and feed: abamectin, doramectin, emamectin, eprinomectin, ivermectin and moxidectin. Samples were extracted, purified and analysed by HPLC-FLD after ...
DOI:
10.1080/19440049.2013.781275
PubMed:
23566301

68. Determination of non-ionic and anionic surfactants in industrial products by separation on a weak ion-exchanger, derivatization and liquid chromatography

Author:
L. Ripoll-Seguer; M. Beneito-Cambra; J.M. Herrero-Martínez; E.F. Simó-Alfonso; G. Ramis-Ramos
Source:
Journal of chromatography 2013 v.1320 no. pp. 66-71
ISSN:
0021-9673
Subject:
acetic acid; acetonitrile; ammonia; anionic surfactants; cations; derivatization; esterification; gels; hydrophobicity; laundry; liquid chromatography; methanol; pH; phthalic anhydride; solid phase extraction; solvents; sulfates; sulfonates; transesterification; washing
Abstract:
... A method for the determination of priority surfactants, including fatty alcohol ethoxylates (FAE), alkylether sulfates (AES) and linear alkylbenzene sulfonates (LAS) is described. The samples were diluted with 50% methanol at pH 4 prior to solid-phase extraction on a weak anionic exchanger (WAX). The AES and LAS surfactant classes were retained, whereas the non-ionic components, including most FAE ...
DOI:
10.1016/j.chroma.2013.10.046

69. Isotopomer enrichment assay for very short chain fatty acids and its metabolic applications

Author:
Kristyen Tomcik; Rafael A. Ibarra; Sushabhan Sadhukhan; Yong Han; Gregory P. Tochtrop; Guo-Fang Zhang
Source:
Analytical biochemistry 2011 v.410 no.1 pp. 110-117
ISSN:
0003-2697
Subject:
acetic acid; acetyl coenzyme A; bicarbonates; butyric acid; derivatization; formic acid; gas chromatography-mass spectrometry; ionization; liver; pH; propionic acid; rats; temperature; tissues
Abstract:
... The present work illustrated an accurate GC/MS measurement for the low isotopomer enrichment assay of formic acid, acetic acid, propionic aicd, butyric acid, and pentanoic acid. The pentafluorobenzyl bromide derivatives of these very short chain fatty acids have high sensitivity of isotopoic enrichment due to their low natural isotopomer distribution in negative chemical ionization mass spectromet ...
DOI:
10.1016/j.ab.2010.11.030
PubMed:
21112315
PubMed Central:
PMC3055175

70. Limits of detection for the determination of mono- and dicarboxylic acids using gas and liquid chromatographic methods coupled with mass spectrometry

Author:
Jana Šťávová; Josef Beránek; Eric P. Nelson; Bonnie A. Diep; Alena Kubátová
Source:
Journal of chromatography 2011 v.879 no.17-18 pp. 1429-1438
ISSN:
1570-0232
Subject:
acetic acid; derivatization; detection limit; dicarboxylic acids; esterification; flame ionization; formic acid; gas chromatography-mass spectrometry; liquid chromatography; monitoring
Abstract:
... The chromatographic separation and instrumental limits of detection (LODs) were obtained for a broad range of C₁–C₁₈ monocarboxylic (MCAs) and C₂–C₁₄ dicarboxylic acids (DCAs) employing either chemical derivatization followed by gas chromatography–mass spectrometry and flame ionization detection (GC–MS/FID) or direct analysis with liquid chromatography high resolution MS and tandem MS (LC–MS). Sui ...
DOI:
10.1016/j.jchromb.2010.11.027
PubMed:
21185238
PubMed Central:
PMC3090519

71. Microwave-assisted derivatisation and LC-MS/MS determination of nitrofuran metabolites in farm-raised prawns (Penaeus monodon)

Author:
Venkatesh Palaniyappan; Arun Kumar Nagalingam; Hari Prasad Ranganathan; Krishnamoorthy Bharathi Kandhikuppam; Hari Prasath Kothandam; Soumya Vasu
Source:
Food additives & contaminants 2013 v.30 no.10 pp. 1739-1744
ISSN:
1944-0057
Subject:
acetic acid; derivatization; seafoods; acetonitrile; Penaeus monodon; methodology; shrimp; metabolites; India
Abstract:
... A new microwave-assisted derivatisation and LC-MS/MS method has been developed for the analysis of nitrofuran metabolites – 3-amino-5-morpholino-methyl-1,3-oxa-zolidinone (AMOZ), 3-amino-2-oxazolidinone (AOZ), 1-aminohydantoin (AHD) and semicarbazide (SEM) – in farm-raised prawns (Penaeus monodon) from the coastal regions of South India. Analysis was carried out by reverse-phase column (Phenomenex ...
DOI:
10.1080/19440049.2013.816896
PubMed:
23883190

72. Novel biobased epoxy compounds: epoxidized sucrose esters of fatty acids

Author:
Xiao Pan; Partha Sengupta; Dean C. Webster
Source:
Green chemistry 2011 v.13 no.4 pp. 965-975
ISSN:
1463-9270
Subject:
Fourier transform infrared spectroscopy; acetic acid; catalysts; chemical bonding; crosslinking; derivatization; desorption; differential scanning calorimetry; epoxidation reactions; epoxides; epoxy compounds; fatty acids; green chemistry; hydrogen peroxide; ion exchange resins; matrix-assisted laser desorption-ionization mass spectrometry; nuclear magnetic resonance spectroscopy; peracetic acid; sucrose; sucrose esters; thermal properties; thermogravimetry; vegetable oil; viscosity
Abstract:
... Novel biobased high functionality epoxy resins were synthesized by the epoxidation of sucrose ester resins of vegetable oil fatty acids (SEFA). A series of sucrose esters of fatty acids were epoxidized by peracetic acid generated in situ from hydrogen peroxide and acetic acid in the presence of an ion exchange resin catalyst to produce the epoxidized sucrose esters of fatty acids (ESEFA). The conv ...
DOI:
10.1039/c0gc00882f

73. Rapid quantification of major reaction products formed during thermochemical pretreatment of lignocellulosic biomass using GC–MS

Author:
James F. Humpula; Shishir P.S. Chundawat; Ramin Vismeh; A. Daniel Jones; Venkatesh Balan; Bruce E. Dale
Source:
Journal of chromatography 2011 v.879 no.13-14 pp. 1018-1022
ISSN:
1570-0232
Subject:
acetic acid; acetone; acetonitrile; ammonia; biofuels; biomass; byproducts; cell walls; corn stover; derivatization; furfural; gas chromatography-mass spectrometry; lignocellulose; liquid chromatography; methanol; solvents
Abstract:
... Accurate quantification of reaction products formed during thermochemical pretreatment of lignocellulosic biomass would lead to a better understanding of plant cell wall deconstruction for production of cellulosic biofuels and biochemicals. However, quantification of some process byproducts, most notably acetamide, acetic acid and furfural, present several analytical challenges using conventional ...
DOI:
10.1016/j.jchromb.2011.02.049

74. Selective liquid chromatographic separation of yttrium from heavier rare earth elements using acetic acid as a novel eluent

Author:
Dejene Kifle; Grethe Wibetoe
Source:
Journal of chromatography 2013 v.1307 no. pp. 86-90
ISSN:
0021-9673
Subject:
absorbance; acetic acid; derivatization; high performance liquid chromatography; oxides; rare earth elements; wavelengths; yttrium
Abstract:
... One of the major difficulties in the rare earth elements separation is purification of yttrium from heavy rare earth elements. Thus, an HPLC method using acetic acid as novel eluent was explored for selective separation of yttrium form the heavy rare earth elements. When acetic acid is used as a mobile phase yttrium eluted with the lighter lanthanides. This is contrary to its relative position amo ...
DOI:
10.1016/j.chroma.2013.07.070

75. Simultaneous determination of phytohormones containing carboxyl in crude extracts of fruit samples based on chemical derivatization by capillary electrophoresis with laser-induced fluorescence detection

Author:
Hao Chen; Xiao-Feng Guo; Hua-Shan Zhang; Hong Wang
Source:
Journal of chromatography 2011 v.879 no.20 pp. 1802-1808
ISSN:
1570-0232
Subject:
abscisic acid; acetic acid; bananas; capillary electrophoresis; chromatography; derivatization; detection limit; fluorescein; fluorescence; fruit extracts; gibberellic acid; indole acetic acid; indole butyric acid; jasmonic acid; naphthaleneacetic acid
Abstract:
... An efficient and sensitive capillary electrophoresis with laser-induced fluorescence detection (CE–LIF) method has been developed for the simultaneous determination of phytohormones containing carboxyl group, including gibberellic acid, indole-3-acetic acid, abscisic acid, jasmonic acid, indole butyric acid, 1-naphthalene acetic acid and 2,4-dichloro-phenoxy acetic acid, based on the chemical deri ...
DOI:
10.1016/j.jchromb.2011.05.002

76. Structural features and thermal degradation properties of various lignin macromolecules obtained from poplar wood (Populus albaglandulosa)

Author:
Jae-Young Kim; Shinyoung Oh; Hyewon Hwang; Ung-Jin Kim; Joon Weon Choi
Source:
Polymer degradation and stability 2013 v.98 no.9 pp. 1671-1678
ISSN:
0141-3910
Subject:
temperature; thermal stability; acetic acid; derivatization; thermogravimetry; wood; lignin; pyrolysis; Populus; ionic liquids; phenolic compounds
Abstract:
... Four different lignins obtained from poplar wood (milled wood lignin: ML, organosolv lignin: OL, ionic liquid lignin: IL and Klason lignin: KL) were subjected to several types of chemical/thermal analyses to compare their structural features and thermal decomposition properties. The ML, OL, IL and KL yield from poplar wood was 5.5, 3.9, 5.8, 19.5 wt%, respectively. Functional group analysis reveal ...
DOI:
10.1016/j.polymdegradstab.2013.06.008

77. Validation study on avermectine residues in foodstuffs

Author:
L. Giannetti; A. Giorgi; F. Necci; G. Ferretti; F. Buiarelli; B. Neri
Source:
Analytica chimica acta 2011 v.700 no.1-2 pp. 11-15
ISSN:
0003-2670
Subject:
acetic acid; acetonitrile; adverse effects; derivatization; doramectin; eggs; eprinomectin; fluorescence; food animals; foods; high performance liquid chromatography; ivermectin; liquid-liquid extraction; maximum residue limits; milk; moxidectin; muscles; veterinary drugs
Abstract:
... Avermectines are antiparasitic agents widely used as veterinary drugs for food producing animals. The European Community, due to their side effects, limited the use of these molecules establishing maximum residue limits (MRLs) in some foods. A validated qualitative and quantitative high performance liquid chromatography method with fluorescence detection (HPLC-FL) is presented for the simultaneous ...
DOI:
10.1016/j.aca.2010.12.035

78. Determination of deoxynivalenol and nivalenol by liquid chromatography and fluorimetric detection with on-line chemical post-column derivatization

Author:
Marilena Muscarella; Marco Iammarino; Donatella Nardiello; Carmen Palermo; Diego Centonze
Source:
Talanta 2012 v.97 no. pp. 145-149
ISSN:
0039-9140
Subject:
acetic acid; acetonitrile; ammonium acetate; correlation; deoxynivalenol; derivatization; detection limit; fluorescence; fluorometry; food contamination; grains; liquid chromatography; nivalenol; quantitative analysis; sodium hydroxide; sunflower oil; wavelengths
Abstract:
... A rapid, sensitive and selective analytical method was developed for the quantitative determination of deoxynivalenol (DON) and nivalenol (NIV) in cereals intended for human and animal consumption. The method, based on liquid chromatography and fluorescence detection, involves an automated 2 channel post-column derivatization, performed with sodium hydroxide, methyl acetoacetate and ammonium aceta ...
DOI:
10.1016/j.talanta.2012.04.009

79. Improved sample preparation method for glycan analysis of glycoproteins by CE-LIF and CE-MS

Author:
Szabo, Zoltan; Guttman, András; Rejtar, Tomas; Karger, Barry L.
Source:
Electrophoresis 2010 v.31 no.8 pp. 1389-1395
ISSN:
0173-0835
Subject:
acetic acid; biotechnology; catalysts; citric acid; derivatization; electrophoresis; electrospray ionization mass spectrometry; fluorescent dyes; glucose; glycoproteins; industry; polysaccharides; sialic acids
Abstract:
... CE is a high-resolution separation technique broadly used in the biotechnology industry for carbohydrate analysis. The standard sample preparation protocol for CE analysis of glycans released from glycoproteins generally requires derivatization times of overnight at 37°C, using ≥100 fold excess of fluorophore reagent, 8-aminopyrene-1,3,6-trisulfonic-acid, if the sample is unknown, or it is a regul ...
DOI:
10.1002/elps.201000037
PubMed:
20309892
PubMed Central:
PMC2898890

80. Matrix solid-phase dispersion on column clean-up/pre-concentration as a novel approach for fast isolation of abuse drugs from human hair

Author:
Míguez-Framil, Martha; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar; Álvarez-Freire, Iván; Tabernero, María Jesús; Bermejo, Ana María
Source:
Journal of chromatography 2010 v.1217 no.41 pp. 6342-6349
ISSN:
0021-9673
Subject:
acetic acid; aluminum oxide; boric acid; cocaine; codeine; confidence interval; derivatization; enzymatic hydrolysis; evaporation; gas chromatography; humans; hydrochloric acid; illicit drugs; methanol; morphine; nitrogen; pH; pretreatment; sodium hydroxide; solid phase extraction; solvents
Abstract:
... A simple and fast sample pre-treatment method based on matrix solid-phase dispersion (MSPD) for isolating cocaine, benzoylecgonine (BZE), codeine, morphine and 6-monoacethylmorphine (6-MAM) from human hair has been developed. The MSPD approach consisted of using alumina (1.80g) as a dispersing agent and 0.6M hydrochloric acid (4mL) as an extracting solvent. For a fixed hair sample mass of 0.050g, ...
DOI:
10.1016/j.chroma.2010.08.034

81. Microwave-assisted Kochetkov amination followed by permanent charge derivatization: a facile strategy for glycomics

Author:
Xin Liu; Guisen Zhang; Kenneth Chan; Jianjun Li
Source:
Chemical communications 2010 v.46 no.39 pp. 7424-7426
ISSN:
1364-548X
Subject:
acetic acid; amination; amines; chemical communication; derivatization; detection limit; glycomics; microwave treatment; oligosaccharides
Abstract:
... We report a simple and rapid microwave-assisted method for the preparation of oligosaccharide-glycosylamines, followed by labelling with tris(2,4,6-trimethoxyphenyl)phosphonium acetic acid N-hydroxysuccinimide ester. The facile strategy introduced a permanent charge at the reducing end of the oligosaccharide. In combination of MALDI-MS, the detection limit for maltoheptaose was as low as 2 fmol μL ...
DOI:
10.1039/c0cc01732a

82. Quantitative determination of fluoxetine in human serum by high performance thin layer chromatography

Author:
Mennickent, Sigrid; Fierro, Ricardo; Vega, Mario; De Diego, Marta; Godoy, C. Gloria
Source:
Journal of separation science 2010 v.33 no.14 pp. 2206-2210
ISSN:
1615-9306
Subject:
acetic acid; correlation; densitometry; derivatization; humans; liquid-liquid extraction; patients; silica gel; thin layer chromatography; toluene
Abstract:
... A high performance thin layer chromatographic method was developed and validated for the quantification of fluoxetine in human serum. Fluoxetine was extracted by liquid-liquid extraction method with diethyl ether as extraction solvent. Imipramine was used as internal standard. The chromatographic separation was achieved on precoated silica gel F 254 high performance thin layer chromatographic plat ...
DOI:
10.1002/jssc.200900832
PubMed:
20533339

83. Screening of tetrodotoxin in puffers using gas chromatography-mass spectrometry

Author:
Man, Che Nin; Noor, Norjuliana Mohd; Harn, Gam Lay; Lajis, Razak; Mohamad, Samsur
Source:
Journal of chromatography 2010 v.1217 no.47 pp. 7455-7459
ISSN:
0021-9673
Subject:
Tetraodontidae; acetic acid; alkaline hydrolysis; cost effectiveness; death; derivatization; gas chromatography-mass spectrometry; humans; liquid-liquid extraction; screening; solvents; tetrodotoxin; toxicity
Abstract:
... Tetrodotoxin (TTX), a toxic compound found in some puffers can cause death to humans through consumption. We have developed a simplified method for the screening of TTX in puffers using GC-MS. A puffer tissue of 0.5g was treated with 5mL of 0.1% acetic acid, followed by alkaline hydrolysis, LLE or liquid-liquid extraction and N-methyl-N-TMS-trifluoroacetamide derivatization. The developed method u ...
DOI:
10.1016/j.chroma.2010.09.064

84. Ethyl propiolate as a post-column derivatization reagent for thiols: Development of a green liquid chromatographic method for the determination of glutathione in vegetables

Author:
Constantinos K. Zacharis; Paraskevas D. Tzanavaras; Anastasia Zotou
Source:
Analytica chimica acta 2011 v.690 no.1 pp. 122-128
ISSN:
0003-2670
Subject:
Brussels sprouts; EDTA (chelating agent); acetic acid; acetylcysteine; broccoli; chromatography; derivatization; fluorometry; glutathione; packaging materials; potatoes; temperature; thiols
Abstract:
... The present study reports the development, validation and application of a new green liquid chromatographic method for the determination of glutathione (GSH) in vegetable samples. In this work we introduce—for the first time—ethyl propiolate (EP) as an advantageous post-column derivatization reagent for thiolic compounds. GSH (tR=6.60min) and N-acetylcysteine (NAC, internal standard) (tR=11.80min) ...
DOI:
10.1016/j.aca.2011.02.003

85. Application of a quick, easy, cheap, effective, rugged and safe-based method for the simultaneous extraction of chlorophenols, alkylphenols, nitrophenols and cresols in agricultural soils, analyzed by using gas chromatography-triple quadrupole-mass spectrometry/mass spectrometry

Author:
Padilla-Sánchez, Juan Antonio; Plaza-Bolaños, Patricia; Romero-González, Roberto; Garrido-Frenich, Antonia; Martínez Vidal, José Luis
Source:
Journal of chromatography 2010 v.1217 no.36 pp. 5724-5731
ISSN:
0021-9673
Subject:
acetic acid; agricultural soils; chlorophenols; cresols; derivatization; gas chromatography; nitrophenols; physicochemical properties; pyridines; soil sampling; tandem mass spectrometry
Abstract:
... Due to the different physico-chemical properties of phenols, the development of a methodology for the simultaneous extraction and determination of phenolic compounds belonging to several families, such as chlorophenols (CPs), alkylphenols (APs), nitrophenols (NTPs) and cresols is difficult. This study shows the development and validation of a method for the analysis of 13 phenolic compounds (inclu ...
DOI:
10.1016/j.chroma.2010.07.004

86. 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

87. Utilisation of pH stacking in conjunction with a highly absorbing chromophore, 5-aminofluorescein, to improve the sensitivity of capillary electrophoresis for carbohydrate analysis

Author:
Kazarian, Artaches A.; Hilder, Emily F.; Breadmore, Michael C.
Source:
Journal of chromatography 2008 v.1200 no.1 pp. 84-91
ISSN:
0021-9673
Subject:
absorption; acetic acid; capillary electrophoresis; chromatography; computer simulation; derivatization; detection limit; deuterium; formic acid; glucose; lactose; maltotriose; pH
Abstract:
... This study explores the use of pH stacking in conjunction with 5-aminofluorescein as a derivatization agent for the sensitive analysis of simple sugars such as glucose, lactose and maltotriose by capillary electrophoresis (CE). The derivatization agent was selected on the basis of its extremely high molar absorptivity, its compatibility with a 488nm light-emitting diode (LED) and the fact that it ...
DOI:
10.1016/j.chroma.2008.04.022

88. Combination of ¹H nuclear magnetic resonance spectroscopy and mass spectrometry as tools for investigation of the thermolytic and solvolytic effects : Case of carbamates analysis

Author:
Przybylski, Cédric; Bonnet, Véronique
Source:
Journal of chromatography 2009 v.1216 no.23 pp. 4787-4797
ISSN:
0021-9673
Subject:
acetic acid; acetonitrile; carbaryl; carbofuran; chlorpropham; derivatization; extensibility; gas chromatography; mass spectrometry; nuclear magnetic resonance spectroscopy; solvents; temperature; toluene
Abstract:
... The carbamate pesticides are a well known thermo-sensible compound class. Under unfavourable conditions, these compounds are highly prone to degradation via fragmentation and/or rearrangement mechanisms. Their transformation processes are observed in consequence of two factors: structure with fragile bonds on the one hand and a stressing environment on the other hand leading to a difficult direct ...
DOI:
10.1016/j.chroma.2009.04.016

89. Determination of fatty alcohol ethoxylates with diphenic anhydride derivatization and liquid chromatography with spectrophotometric detection : A comparative study with other anhydrides

Author:
Micó-Tormos, A.; Bianchi, F.; Simó-Alfonso, E.F.; Ramis-Ramos, G.
Source:
Journal of chromatography 2009 v.1216 no.15 pp. 3023-3030
ISSN:
0021-9673
Subject:
acetic acid; acetonitrile; alcohols; anhydrides; derivatization; detection limit; ethylene oxide; maleates; phthalates; reversed-phase high performance liquid chromatography; seawater; urea; wastewater treatment; wavelengths
Abstract:
... A method for the determination of fatty alcohol ethoxylates (FAEs) using diphenic anhydride as derivatization reagent and RP-HPLC separation with UV-vis detection is presented and compared to derivatization with maleic, phthalic, and other cyclic anhydrides. With these anhydrides, the reaction rates increased when urea was added to the reaction medium, and the yields did not decrease when the samp ...
DOI:
10.1016/j.chroma.2009.01.100

90. Study on the migration of bisphenol-A from baby bottles by stir bar sorptive extraction-thermal desorption-capillary GC-MS

Author:
De Coensel, Nathalie; David, Frank; Sandra, Pat
Source:
Journal of separation science 2009 v.32 no.21 pp. 3829-3836
ISSN:
1615-9306
Subject:
acetates; acetic acid; bisphenol A; bottles; correlation; derivatization; microwave treatment; temperature
Abstract:
... Migration of bisphenol-A (BPA), the principal monomer of polycarbonate (PC) baby bottles, was investigated using an aqueous migration simulant. BPA was determined in 200 mL water samples using stir bar sorptive extraction (SBSE) after in situ derivatization with acetic acid anhydride followed by thermal desorption (TD)-capillary GC-MS. The concentration of BPA was calculated using the deuterated i ...
DOI:
10.1002/jssc.200900349
PubMed:
19813229

91. Analysis of amino acids without derivatization in barley extracts by LC-MS-MS

Author:
Björn Thiele; Kerstin Füllner; Nadine Stein; Marco Oldiges; Arnd J. Kuhn; Diana Hofmann
Source:
Analytical and bioanalytical chemistry 2008 v.391 no.7 pp. 2663-2672
ISSN:
1618-2642
Subject:
acetic acid; amino acids; ammonium acetate; barley; cation exchange; derivatization; detection limit; free amino acids; liquid chromatography; plant tissues; roots; shoots; solvents; tandem mass spectrometry; temperature
Abstract:
... A method has been developed for quantification of 20 amino acids as well as 13 ¹⁵N-labeled amino acids in barley plants. The amino acids were extracted from plant tissues using aqueous HCl–ethanol and directly analyzed without further purification. Analysis of the underivatized amino acids was performed by liquid chromatography (LC)–electrospray ionization (ESI) tandem mass spectrometry (MS-MS) in ...
DOI:
10.1007/s00216-008-2167-9
PubMed:
18506428

92. Determination of fatty alcohol ethoxylates by derivatisation with maleic anhydride followed by liquid chromatography with UV-vis detection

Author:
Micó-Tormos, A.; Collado-Soriano, C.; Torres-Lapasió, J.R.; Simó-Alfonso, E.; Ramis-Ramos, G.
Source:
Journal of chromatography 2008 v.1180 no.1-2 pp. 32-41
ISSN:
0021-9673
Subject:
acetic acid; acetonitrile; algorithms; anhydrides; carbon; cleaning agents; derivatization; esterification; ethylene oxide; fatty alcohols; liquid chromatography; melting; rivers; seawater; solid phase extraction; temperature; urea
Abstract:
... The esterification of fatty alcohol ethoxylates (FAEs) by melting with maleic anhydride has been studied in the presence of urea. The reaction rate and yield of non-ethoxylated and ethoxylated alcohols increase largely when grinded urea is suspended in the reaction medium, a 100% yield being achieved at 80°C in 15min. The procedure is tolerant to the presence of large amounts of water. The UV-vis ...
DOI:
10.1016/j.chroma.2007.11.105

93. Determination of fatty alcohol ethoxylates by derivatization with phthalic anhydride followed by liquid chromatography with UV-vis detection

Author:
Micó-Tormos, A.; Simó-Alfonso, E.F.; Ramis-Ramos, G.
Source:
Journal of chromatography 2008 v.1203 no.1 pp. 47-53
ISSN:
0021-9673
Subject:
acetic acid; acetonitrile; alcohols; cleaning agents; derivatization; esterification; ethylene oxide; liquid chromatography; phthalic anhydride; prediction; rivers; seawater; solid phase extraction; temperature; urea
Abstract:
... The esterification of fatty alcohol ethoxylates (FAEs) with phthalic anhydride in 1,4-dioxane was studied. At 110°C and in the presence of urea, which increased the reaction rate, esterification was completed in 60min. The reaction yield did not decrease when the sample contained up to 50% water. For the non-ethoxylated alcohols, the UV-vis response factors of the derivatives were not significantl ...
DOI:
10.1016/j.chroma.2008.07.017

94. Measurement of ambient hydroperoxides using an automated HPLC system and various factors which affect variations of their concentrations in Korea

Author:
Hong, Sang B.; Kim, Gyu S.; Kang, Chang H.; Lee, Jai H.
Source:
Environmental monitoring and assessment 2008 v.147 no.1-3 pp. 23-34
ISSN:
0167-6369
Subject:
acetic acid; air; catalysts; derivatization; detection limit; glass; high performance liquid chromatography; hydrogen peroxide; hydroperoxides; nitrogen oxides; ozone; peroxidase; relative humidity; sand; solar radiation; temperature; Korean Peninsula
Abstract:
... An HPLC system was automated for the measurement of gaseous hydroperoxides in the ambient air. In this system, samples collected using a glass coil without a long sampling tube are injected automatically into HPLC. The analytical system is based on the post-column derivatization, which is a reaction of hydroperoxides with p-hydroxyphenyl acetic acid to produce a fluorescent dimer in the presence o ...
DOI:
10.1007/s10661-007-0094-4
PubMed:
18181026

95. Optimized derivatization of acidic herbicides with trimethylsilyldiazomethane for GC analysis

Author:
Ranz, Andreas; Korpecka, Justyna; Lankmayr, Ernst
Source:
Journal of separation science 2008 v.31 no.4 pp. 746-752
ISSN:
1615-9306
Subject:
2,4,5-T; 2,4-D; MCPA (herbicide); MCPB (herbicide); acetic acid; automation; derivatization; esters; mecoprop; methanol; propionic acid; quality control; temperature
Abstract:
... In the present study, the preparation of methyl esters of chlorophenoxy acids with trimethylsilyldiazomethane (TMSD) is reported. TMSD is a mild and safe alternative to the highly toxic, thermally labile, and explosive diazomethane. Due to the novelty of this method, the characteristics of the reaction were investigated and the derivatization procedure was screened for statistically significant fa ...
DOI:
10.1002/jssc.200700437
PubMed:
18264987

96. Rapid characterization of fatty alcohol ethoxylates by non-aqueous capillary electrophoresis

Author:
Arias, Mónica; Bauza, Roberto; Rodríguez, Juana; Castañeda, Gregorio; Ríos, Ángel
Source:
Electrophoresis 2008 v.29 no.14 pp. 3060-3068
ISSN:
0173-0835
Subject:
acetic acid; ammonium nitrate; capillary electrophoresis; derivatization; ethylene oxide; high performance liquid chromatography; industry; methanol; microwave radiation; nonionic surfactants; petroleum; polyurethanes; streams
Abstract:
... Fatty alcohol ethoxylates (FAE) (a mixture of nonionic surfactants) have been characterized using NACE with UV detection. Phenyl polyurethane derivatives of these compounds were previously obtained by reaction with phenyl isocyanate. The derivatization reaction only requires microwave irradiation for 30 s (600 W). Phenyl polyurethanes were separated and characterized using a BGE containing a mixtu ...
DOI:
10.1002/elps.200700948

97. Analytical procedure for determination of the time profile of eprinomectin excretion in sheep faeces

Author:
Kožuh Eržen, Nevenka; Hodošček, Lena; Cerkvenik-Flajs, Vesna
Source:
Analytical and bioanalytical chemistry 2007 v.387 no.4 pp. 1329-1335
ISSN:
1618-2642
Subject:
acetic acid; acetonitrile; cleaning; derivatization; detection limit; drugs; ecotoxicology; eprinomectin; excretion; feces; fluorescence; high performance liquid chromatography; sheep; solid phase extraction
Abstract:
... An analytical procedure has been introduced to enable study of the time profile of eprinomectin excretion in sheep faeces. Eprinomectin was extracted from sheep faeces with acetonitrile, the extract was cleaned by solid-phase extraction (SPE), and, after derivatization by reaction with N-methylimidazole, trifluoroacetic anhydride, and acetic acid, eprinomectin was analysed by high-performance liqu ...
DOI:
10.1007/s00216-006-0903-6
PubMed:
17109134

98. Purification and identification of cutinases from Colletotrichum kahawae and Colletotrichum gloeosporioides

Author:
Zhenjia Chen; Catarina F. Franco; Ricardo P. Baptista; Joaquim M. S. Cabral; Ana V. Coelho; Carlos J. Rodrigues Jr.; Eduardo P. Melo
Source:
Applied microbiology and biotechnology 2007 v.73 no.6 pp. 1306-1313
ISSN:
0175-7598
Subject:
Colletotrichum kahawae; Glomerella cingulata; acetic acid; acid deposition; ammonium sulfate; blight; carbon; carboxylesterase; chromatography; coffee beans; coffee berry disease; culture media; cutin; cutinase; derivatization; developmental stages; electrophoresis; fungi; leaves; mass spectrometry; molecular weight; proteins; small fruits; tributyrin
Abstract:
... Colletotrichum kahawae is the causal agent of the coffee berry disease, infecting leaves and coffee berries at any stage of their development. Colletotrichum gloeosporioides is the causal agent of brown blight, infecting ripe berries only. Both fungi secrete the same pattern of carboxylesterases to the fermentation broth when cutin is used as carbon source. By using two different strategies compos ...
DOI:
10.1007/s00253-006-0605-1
PubMed:
17043825

99. Comparison and evaluation of analysis procedures for the quantification of (2-methoxyethoxy)acetic acid in urine

Author:
B'Hymer, Clayton; Butler, Mary Ann; Cheever, Kenneth L.
Source:
Analytical and bioanalytical chemistry 2005 v.383 no.2 pp. 201-209
ISSN:
1618-2642
Subject:
acetic acid; biomarkers; derivatization; detection limit; esterification; ethanol; ethyl acetate; fuels; gas chromatography; humans; industrial applications; liquid-liquid extraction; metabolites; solid phase extraction; spectrometers; urine
Abstract:
... Several extraction and derivatization procedures were evaluated for the quantification of (2-methoxyethoxy)acetic acid (MEAA) in urine. MEAA is a metabolite and a biomarker for exposure to 2-(2-methoxyethoxy)ethanol, a glycol ether with widespread use in various industrial applications and the specific use as an anti-icing additive in the military jet fuel formulation JP-8. Quantification of glyco ...
DOI:
10.1007/s00216-005-0048-z

100. Solid-phase extraction-liquid chromatography-fluorimetry for organotin speciation in natural waters

Author:
E. González-Toledo; A. Ortuño; R. Compañó; M. Granados; M. D. Prat
Source:
Chromatographia 2002 v.55 no.1-2 pp. 19-24
ISSN:
0009-5893
Subject:
acetic acid; coasts; derivatization; dibutyltin; fluorometry; methanol; reversed-phase high performance liquid chromatography; seawater; solid phase extraction; tin; tributyltin
Abstract:
... A method is reported for the determination of dibutyltin (DBT), diphenyltin (DPhT), tributyltin (TBT), and triphenyltin (TPhT) species at the nanogram per litre concentration level in natural water samples. Analytes were isolated from samples by solid-phase extraction and analysed both off-line and on-line by reversed-phase high-performance liquid chromatography with post-column derivatization and ...
DOI:
10.1007/BF02492309