Base de dados : MEDLINE
Pesquisa : D02.626.080 [Categoria DeCS]
Referências encontradas : 4183 [refinar]
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[PMID]:29329094
[Au] Autor:Sentkowska A; Pyrzynska K
[Ad] Endereço:University of Warsaw, Heavy Ion Laboratory, Pasteura 5A, 02-093 Warsaw, Poland. Electronic address: sentkowska@slcj.uw.edu.pl.
[Ti] Título:Hydrophilic interaction liquid chromatography in the speciation analysis of selenium.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1074-1075:8-15, 2018 Feb 01.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The hydrophilic interaction liquid chromatography (HILIC) coupled to mass spectrometry was employed to study retention behavior of selected selenium compounds using two different HILIC stationary phases: silica and zwitterionic. Two organic solvents - acetonitrile and methanol - were compared as a component of mobile phase. Separation parameters such as a content of organic modifier, the eluent pH and inorganic buffer concentration were investigated. Based on all observations, methanol seems to be beneficial for the separation of studied compounds. The optimal HILIC separation method involved silica column and eluent composed of 85% MeOH and CH COONH (8 mM, pH 7) was compared to RP method in terms of time of the single run, the separation efficiency and limit of detection.
[Mh] Termos MeSH primário: Cromatografia Líquida/métodos
Compostos de Selênio
Selênio
[Mh] Termos MeSH secundário: Acetonitrilos/química
Interações Hidrofóbicas e Hidrofílicas
Metanol/química
Cebolas/química
Extratos Vegetais/química
Folhas de Planta/química
Selênio/análise
Selênio/química
Selênio/classificação
Compostos de Selênio/análise
Compostos de Selênio/química
Compostos de Selênio/classificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Plant Extracts); 0 (Selenium Compounds); H6241UJ22B (Selenium); Y4S76JWI15 (Methanol); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180113
[St] Status:MEDLINE


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[PMID]:29247927
[Au] Autor:Tu X; Sun F; Wu S; Liu W; Gao Z; Huang S; Chen W
[Ad] Endereço:College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou, China; MOE Engineering Research Center of Bee Products Processing and Application, Fujian Agriculture and Forestry University, Fuzhou, China.
[Ti] Título:Comparison of salting-out and sugaring-out liquid-liquid extraction methods for the partition of 10-hydroxy-2-decenoic acid in royal jelly and their co-extracted protein content.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1073:90-95, 2018 Jan 15.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Homogeneous liquid-liquid extraction (h-LLE) has been receiving considerable attention as a sample preparation method due to its simple and fast partition of compounds with a wide range of polarities. To better understand the differences between the two h-LLE extraction approaches, salting-out assisted liquid-liquid extraction (SALLE) and sugaring-out assisted liquid-liquid extraction (SULLE), have been compared for the partition of 10-hydroxy-2-decenoic acid (10-HDA) from royal jelly, and for the co-extraction of proteins. Effects of the amount of phase partition agents and the concentration of acetonitrile (ACN) on the h-LLE were discussed. Results showed that partition efficiency of 10-HDA depends on the phase ratio in both SALLE and SULLE. Though the partition triggered by NaCl and glucose is less efficient than MgSO in the 50% (v/v) ACN-water mixture, their extraction yields can be improved to be similar with that in MgSO SALLE by increasing the initial concentration of ACN in the ACN-water mixture. The content of co-extracted protein was correlated with water concentration in the obtained upper phase. MgSO showed the largest protein co-extraction at the low concentration of salt. Glucose exhibited a large protein co-extraction in the high phase ratio condition. Furthermore, NaCl with high initial ACN concentration is recommended because it produced high extraction yield for 10-HDA and the lowest amount of co-extracted protein. These observations would be valuable for the sample preparation of royal jelly.
[Mh] Termos MeSH primário: Ácidos Graxos Monoinsaturados/isolamento & purificação
Ácidos Graxos/química
Glucose/química
Extração Líquido-Líquido/métodos
Proteínas/isolamento & purificação
Cloreto de Sódio/química
[Mh] Termos MeSH secundário: Acetonitrilos
Ácidos Graxos Monoinsaturados/análise
Proteínas/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Fatty Acids); 0 (Fatty Acids, Monounsaturated); 0 (Proteins); 451W47IQ8X (Sodium Chloride); 765-01-5 (10-hydroxy-2-decenoic acid); IY9XDZ35W2 (Glucose); L497I37F0C (royal jelly); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180302
[Lr] Data última revisão:
180302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171217
[St] Status:MEDLINE


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[PMID]:29241085
[Au] Autor:Alshishani A; Salhimi SM; Saad B
[Ad] Endereço:School of Chemical Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia. Electronic address: anasshishani@gmail.com.
[Ti] Título:Salting-out assisted liquid-liquid extraction coupled with hydrophilic interaction chromatography for the determination of biguanides in biological and environmental samples.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1073:51-59, 2018 Jan 15.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A new salting-out assisted liquid-liquid extraction (SALLE) sample preparation method for the determination of the polar anti-diabetic biguanide drugs (metformin, buformin and phenformin) in blood plasma, urine and lake water samples were developed. The SALLE was performed by mixing samples (plasma (0.2mL), urine or lake water (1.0mL)) with acetonitrile (0.4mL for plasma, 0.5mL for urine or lake water), sodium hydroxide powder was then added for the phase separation. The effects of type of salting-out reagent, type of extraction solvent, volumes of acetonitrile and sample, amount of sodium hydroxide, vortexing and centrifugation times on the extraction efficiency were investigated. The upper layer, containing the biguanides, was directly injected into a HPLC unit using ZIC-HILIC column (150mm×2.1mm×3.5µm) and was detected at 236nm. The method was validated and calibration curves were linear with r >0.99 over the range of 20-2000µgL for plasma and 5-2000µgL for urine and lake water samples. The limits of detection were in the range (3.8-5.6)µgL , (0.8-1.5)µgL and (0.3-0.8)µgL for plasma, urine and lake water, respectively. The accuracies in the three matrices were within 87.3-103%, 87.4-109%, 82.2-109% of the nominal concentration for metformin, buformin and phenformin, respectively. The relative standard deviation for inter- and intra -day precision were in the range of 1.0-17% for all analytes in the three matrices.
[Mh] Termos MeSH primário: Biguanidas/análise
Biguanidas/isolamento & purificação
Cromatografia Líquida de Alta Pressão/métodos
Extração Líquido-Líquido/métodos
Poluentes Químicos da Água/análise
Poluentes Químicos da Água/isolamento & purificação
[Mh] Termos MeSH secundário: Acetonitrilos
Biguanidas/química
Biguanidas/urina
Seres Humanos
Interações Hidrofóbicas e Hidrofílicas
Lagos/química
Limite de Detecção
Modelos Lineares
Reprodutibilidade dos Testes
Cloreto de Sódio
Poluentes Químicos da Água/química
Poluentes Químicos da Água/urina
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Biguanides); 0 (Water Pollutants, Chemical); 451W47IQ8X (Sodium Chloride); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180302
[Lr] Data última revisão:
180302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171215
[St] Status:MEDLINE


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[PMID]:29229333
[Au] Autor:Abu Kassim NS; Shaw PN; Hewavitharana AK
[Ad] Endereço:School of Pharmacy, The University of Queensland, QLD 4072, Australia.
[Ti] Título:Simultaneous determination of 12 vitamin D compounds in human serum using online sample preparation and liquid chromatography-tandem mass spectrometry.
[So] Source:J Chromatogr A;1533:57-65, 2018 Jan 19.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The development and validation of a method to simultaneously quantify 12 vitamin D compounds in human serum by LC-MS/MS is described. The main challenge was that of extracting and chromatographing vitamin D compounds with a range of polarities, both lipophilic and hydrophilic, in a single analytical procedure. The extractions of all 12 vitamin D compounds were achieved by an optimised protein precipitation method using acetonitrile as the precipitant, and the separation was accomplished by using a pentafluorophenyl (PFP) column. The sensitivity was increased by minimising matrix effects in MS detector rather than using a lengthy derivatisation procedure; an online solid phase extraction (SPE) using a PFP guard column was used for cleanup. Detection limits for all compounds were in the picomole range when using a 500µL sample volume. Recovery percentages ranged from 92% to 99%. LC-MS/MS resolution of all 12 vitamin D compounds, including the chromatographic separation of 25(OH)D from the isomer 3-epi-25(OH)D was achieved. Stable isotope labelled vitamin D compounds were used as internal standards for the quantification of all 12 vitamin D compounds. This is a simple yet accurate, selective, and sensitive method for the quantification of 12 major vitamin D compounds, including the sulfated forms, in human serum. The method is sufficiently robust to offer potential for use in routine analysis in a pathology laboratory setting.
[Mh] Termos MeSH primário: Análise Química do Sangue/métodos
Cromatografia Líquida
Espectrometria de Massas em Tandem
Vitamina D/sangue
[Mh] Termos MeSH secundário: Acetonitrilos/química
Calcifediol/sangue
Seres Humanos
Isótopos/análise
Limite de Detecção
Extração em Fase Sólida
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Isotopes); 1406-16-2 (Vitamin D); P6YZ13C99Q (Calcifediol); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180227
[Lr] Data última revisão:
180227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171213
[St] Status:MEDLINE


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[PMID]:28851528
[Au] Autor:Slimani K; Féret A; Pirotais Y; Maris P; Abjean JP; Hurtaud-Pessel D
[Ad] Endereço:ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Fougères Laboratory, Residues and Contaminants Analysis Unit, France.
[Ti] Título:Liquid chromatography-tandem mass spectrometry multiresidue method for the analysis of quaternary ammonium compounds in cheese and milk products: Development and validation using the total error approach.
[So] Source:J Chromatogr A;1517:86-96, 2017 Sep 29.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Quaternary ammonium compounds (QACs) are both cationic surfactants and biocidal substances widely used as disinfectants in the food industry. A sensitive and reliable method for the analysis of benzalkonium chlorides (BACs) and dialkyldimethylammonium chlorides (DDACs) has been developed that enables the simultaneous quantitative determination of ten quaternary ammonium residues in dairy products below the provisional maximum residue level (MRL), set at 0.1mgkg . To the best of our knowledge, this method could be the one applicable to milk and to three major processed milk products selected, namely processed or hard pressed cheeses, and whole milk powder. The method comprises solvent extraction using a mixture of acetonitrile and ethyl acetate, without any further clean-up. Analyses were performed by liquid chromatography coupled with electrospray tandem mass spectrometry detection (LC-ESI-MS/MS) operating in positive mode. A C18 analytical column was used for chromatographic separation, with a mobile phase composed of acetonitrile and water both containing 0.3% formic acid; and methanol in the gradient mode. Five deuterated internal standards were added to obtain the most accurate quantification. Extraction recoveries were satisfactory and no matrix effects were observed. The method was validated using the total error approach in accordance with the NF V03-110 standard in order to characterize the trueness, repeatability, intermediate precision and analytical limits within the range of 5-150µgkg for all matrices. These performance criteria, calculated by e.noval 3.0 software, were satisfactory and in full accordance with the proposed provisional MRL and with the recommendations in the European Union SANTE/11945/2015 regulatory guidelines. The limit of detection (LOD) was low (<1.9µgkg ) and the limit of quantification (LOQ) ranged from 5µgkg to 35µgkg for all matrices depending on the analytes. The validation results proved that the method is suitable for quantifying quaternary ammoniums in foodstuffs from dairy industries at residue levels, and could be used for biocide residues monitoring plans and to measure the exposition consumer to biocides products.
[Mh] Termos MeSH primário: Queijo/análise
Cromatografia Líquida de Alta Pressão
Análise de Alimentos/métodos
Leite/química
Compostos de Amônio Quaternário/análise
Espectrometria de Massas em Tandem
[Mh] Termos MeSH secundário: Acetonitrilos/química
Animais
Compostos de Benzalcônio/análise
Limite de Detecção
[Pt] Tipo de publicação:JOURNAL ARTICLE; VALIDATION STUDIES
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Benzalkonium Compounds); 0 (Quaternary Ammonium Compounds); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170831
[St] Status:MEDLINE


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[PMID]:28850891
[Au] Autor:Satomi Y; Hirayama M; Kobayashi H
[Ad] Endereço:Integrated Technology Research Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Japan. Electronic address: yoshinori.satomi@takeda.com.
[Ti] Título:One-step lipid extraction for plasma lipidomics analysis by liquid chromatography mass spectrometry.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1063:93-100, 2017 Sep 15.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:In the past decade, various lipidomics methodologies have been developed using mass spectrometry based analytical technologies, enabling wide coverage lipid detection in a quantitative manner. Hence, lipidomics has become a widely-accepted approach for biomarker discovery and mechanism elucidation in both medical and biology research fields; however, there are still technical challenges. In this study, focusing on the sample preparation procedure, a single step deproteinization by a water-soluble organic solvent, such as methanol (MeOH), ethanol (EtOH), isopropanol (IPA) or acetonitrile (ACN), was evaluated and proved to be satisfactory for lipidomics analysis. Moreover, during this investigation ACN deproteinization was revealed to not be an effective method for lipid extraction because lipid decomposition was observed during the protein precipitation process through lipase activation, potentially due to the insufficient protein denaturation. Therefore, excluding ACN, protein precipitation by alcohol was evaluated as the lipid extraction reagent. Moreover, adding the MTBE-MeOH (mMM) method, one of the major liquid-liquid extraction methods for shotgun lipidomics, these four approaches were compared. Lipids were extracted from mouse plasma by these four methods and used for exhaustive lipid profiling by liquid chromatography mass spectrometry (LC/MS) analysis. Comparison of these four methods revealed that alcohol based protein precipitation was a useful sample preparation procedure for LC/MS based lipidomics analysis. Whereas MeOH extraction was appropriate for hydrophilic lipid species, IPA was effective for hydrophobic lipids such as triacylglycerols (TG). In practice, EtOH extraction is thought to be the best approach to cover wide range of lipid species using a simple preparation procedure.
[Mh] Termos MeSH primário: Fracionamento Químico/métodos
Cromatografia Líquida/métodos
Lipídeos/sangue
Espectrometria de Massas/métodos
[Mh] Termos MeSH secundário: Acetonitrilos
Animais
Precipitação Química
Ácidos Cólicos
Gangliosídeos
Lipídeos/química
Lipídeos/isolamento & purificação
Camundongos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Cholic Acids); 0 (Gangliosides); 0 (Lipids); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170830
[St] Status:MEDLINE


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[PMID]:28837869
[Au] Autor:Yang Y; Tu R; Sun W; Zhu Z; Zhang Y
[Ad] Endereço:Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, Xi'an 710069, China; Biomedicine Key Laboratory of Shaanxi Province, College of Life Science, Northwest University, Xi'an 710069, China.
[Ti] Título:Silver perchlorate in the mobile phase for rapid separation and determination of a pair of positional isomers in Inula racemosa Hook.f. with RP-HPLC.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1063:25-30, 2017 Sep 15.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Alantolactone and isoalantolactone isolated from many species of plants are a pair of positional isomers of CC bond. Previously, alantolactone and isoalantolactone have been proved to be good lead compounds for future anticancer agent development. Similarity of their molecular structures increases the separation difficulty for these two isomers on a conventional C column. Silver perchlorate (AgClO ) as mobile phase additives with RP-HPLC for improving the separation was developed for rapid determination of the positional isomers in Inula racemosa Hook.f. The effects of the concentration of silver perchlorate on the separation of the analytes were investigated. The composition of acetonitrile and water containing 5.0% silver perchlorate in a 65:35 (v/v) ratio was used as mobile phase, in which they were well separated within a short period of time on the C column. The method was successfully applied to determine them in an extract of Inula racemosa Hook.f. root. Silver perchlorate in mobile phase can efficiently improve the separation of the positional isomers and could be applied to rapidly determinate their content in this plant.
[Mh] Termos MeSH primário: Cromatografia Líquida de Alta Pressão/métodos
Inula/química
Lactonas/isolamento & purificação
Percloratos/química
Sesquiterpenos de Eudesmano/isolamento & purificação
Sesquiterpenos/isolamento & purificação
Compostos de Prata/química
[Mh] Termos MeSH secundário: Acetonitrilos/química
Cromatografia de Fase Reversa/métodos
Isomerismo
Lactonas/análise
Lactonas/química
Extratos Vegetais/química
Raízes de Plantas/química
Sesquiterpenos/análise
Sesquiterpenos/química
Sesquiterpenos de Eudesmano/análise
Sesquiterpenos de Eudesmano/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Lactones); 0 (Perchlorates); 0 (Plant Extracts); 0 (Sesquiterpenes); 0 (Sesquiterpenes, Eudesmane); 0 (Silver Compounds); 7783-93-9 (silver perchlorate); BYH07P620U (isoalantolactone); M7GSN5Q1M6 (alantolactone); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170825
[St] Status:MEDLINE


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[PMID]:28780456
[Au] Autor:Zulkarnain; Miyan L; Ahmad A; Fazle Alam M; Younus H
[Ad] Endereço:Department of Chemistry, Faculty of Science, Aligarh Muslim University, Aligarh 202002, UP, India. Electronic address: zulqarnain46@gmail.com.
[Ti] Título:Synthesis, single-crystal, DNA interaction, spectrophotometric and spectroscopic characterization of the hydrogen-bonded charge transfer complex of 2-aminopyrimidine with π-acceptor chloranilic acid at different temperature in acetonitrile.
[So] Source:J Photochem Photobiol B;174:195-208, 2017 Sep.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:The charge transfer (CT) interaction of 2-aminopyrimidine (AP) with chloranilic acid (CLA) as π-acceptor was investigated spectrophotometrically in acetonitrile at different temperatures in the range of 25-50°C. The 1:1 stoichiometry of the synthesized CT complex was detected using straight line method. Benesi-Hildebrand equation was used to determine the association constant (K ), molar extinction coefficient (ε) and other physical parameters. Various thermodynamics parameters such as enthalpy (ΔH), entropy (ΔS) and free energy (ΔG) were determined using UV-Visible spectrophotometry in acetonitrile at different temperatures. H NMR, FTIR, ESI-MS, elemental analyses, and UV-Visible techniques were used to characterize the hydrogen-bonded CT complex. H NMR spectroscopy was also used for the analysis of the CT complex where both hydrogen bond and charge transfer were present in its molecular composition. The interaction of the selected organic compound with Ct-DNA was well investigated using fluorescence spectroscopic method. Stern-Volmer constant (K ) was used to estimate the fluorescence quenching efficiency. Circular dichroism (CD) spectroscopy was employed to measure the conformational change of DNA in the presence of CT complex. Furthermore, the drug CT complex detected changes in its viscosity. The charge transfer complex was formed as a result of the transfer of the lone pair of electrons from donor to the acceptor and exhibits well resolved charge transfer bands in the regions where absorption by both donor and acceptor were absent. The thermal composition and stability of the CT complex were analyzed using thermogravimetric and differential thermal analysis (TGA and DTA) studies. The X-ray crystal structure was used for the interpretation of the structure of the [(AP) (CLA) ] CT complex. The crystal structure indicated that cation and anion are linked through strong N H----O type of hydrogen bond.
[Mh] Termos MeSH primário: Acetonitrilos/química
Benzoquinonas/química
DNA/metabolismo
Pirimidinas/química
Pirimidinas/metabolismo
Temperatura Ambiente
[Mh] Termos MeSH secundário: Animais
Bovinos
Técnicas de Química Sintética
Cristalografia por Raios X
Transporte de Elétrons
Ligações de Hidrogênio
Modelos Moleculares
Conformação Molecular
Pirimidinas/síntese química
Solventes/química
Espectrofotometria
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Benzoquinones); 0 (Pyrimidines); 0 (Solvents); 109-12-6 (2-aminopyrimidine); 9007-49-2 (DNA); YJ8L3BB7Y4 (chloranilic acid); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171012
[Lr] Data última revisão:
171012
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170807
[St] Status:MEDLINE


  9 / 4183 MEDLINE  
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[PMID]:28778530
[Au] Autor:Fontana A; Rodríguez I; Cela R
[Ad] Endereço:Laboratorio de Bioquímica Vegetal, Instituto de Biología Agrícola de Mendoza, Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional de Cuyo, Almirante Brown 500, M5528AHB Chacras de Coria, Argentina. Electronic address: afontana@mendoza-conicet.gob.ar.
[Ti] Título:Accurate determination of 3-alkyl-2-methoxypyrazines in wines by gas chromatography quadrupole time-of-flight tandem mass spectrometry following solid-phase extraction and dispersive liquid-liquid microextraction.
[So] Source:J Chromatogr A;1515:30-36, 2017 Sep 15.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A new reliable method for the determination 3-alkyl-2-methoxypyrazines (MPs) in wine samples based on the sequential combination of solid-phase extraction (SPE), dispersive liquid-liquid microextraction (DLLME) and gas chromatography (GC) quadrupole time-of-flight accurate tandem mass spectrometry (QTOF-MS/MS) is presented. Primary extraction of target analytes was carried out by using a reversed-phase Oasis HLB (200mg) SPE cartridge combined with acetonitrile as elution solvent. Afterwards, the SPE extract was submitted to DLLME concentration using 0.06mL carbon tetrachloride (CCl ) as extractant. Under final working conditions, sample concentration factors above 379 times and limits of quantification (LOQs) between 0.3 and 2.1ngL were achieved. Moreover, the overall extraction efficiency of the method was unaffected by the particular characteristics of each wine; thus, accurate results (relative recoveries from 84 to 108% for samples spiked at concentrations from 5 to 25ngL ) were obtained using matrix-matched standards, without using standard additions over every sample. Highly selective chromatographic records were achieved considering a mass window of 5mDa, centered in the quantification product ion corresponding to each compound. Twelve commercial wines, elaborated with grapes from different varieties and geographical origins, were processed with the optimized method. The 2-isobutyl-3-methoxypyrazine (IBMP) was determined at levels above the LOQs of the method in half of the samples.
[Mh] Termos MeSH primário: Análise de Alimentos/métodos
Cromatografia Gasosa-Espectrometria de Massas
Microextração em Fase Líquida
Pirazinas/análise
Extração em Fase Sólida
Vinho/análise
[Mh] Termos MeSH secundário: Acetonitrilos/química
Limite de Detecção
Solventes/química
Vitis/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Pyrazines); 0 (Solvents); S327O0T12O (2-isobutyl-3-methoxypyrazine); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171012
[Lr] Data última revisão:
171012
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170806
[St] Status:MEDLINE


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[PMID]:28774614
[Au] Autor:Komaki Y; Plewa MJ
[Ad] Endereço:Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States; Safe Global Water Institute, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States. Electronic address: ykomaki@stanford.edu.
[Ti] Título:Investigation of nuclear enzyme topoisomerase as a putative molecular target of monohaloacetonitrile disinfection by-products.
[So] Source:J Environ Sci (China);58:231-238, 2017 Aug.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Disinfection by-products occur widely as the unintended effect of water disinfection and are associated with toxicity and adverse human health effects. Yet the molecular mechanisms of their toxicity are not well understood. To investigate the molecular basis of hyperploidy induction by monohaloacetonitriles, the interaction of monohaloacetonitriles with topoisomerase II in Chinese hamster ovary cells was examined. We showed a concentration-dependent inhibition of DNA decatenation activity of topoisomerase under acellular conditions while in vitro monohaloacetonitrile treatment expressed mixed results. The working hypothesis, that topoisomerase II is a molecular target of monohaloacetonitriles, was only partially supported. Nevertheless, this research serves as a starting point toward molecular mechanisms of toxic action of monohaloacetonitriles.
[Mh] Termos MeSH primário: Acetonitrilos/toxicidade
DNA Topoisomerases Tipo II/metabolismo
Desinfetantes/toxicidade
[Mh] Termos MeSH secundário: Animais
Células CHO
Ciclo Celular
Cricetulus
Dano ao DNA
Purificação da Água
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Disinfectants); EC 5.99.1.3 (DNA Topoisomerases, Type II)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170811
[Lr] Data última revisão:
170811
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170805
[St] Status:MEDLINE



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