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[PMID]:26938207
[Au] Autor:Du B; Su X; Yang K; Pan L; Liu Q; Gong L; Wang P; Yang J; He Y
[Ad] Endereço:School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences , Beijing 100049, China.
[Ti] Título:Antibody-Free Colorimetric Detection of Total Aflatoxins in Rice Based on a Simple Two-Step Chromogenic Reaction.
[So] Source:Anal Chem;88(7):3775-80, 2016 Apr 05.
[Is] ISSN:1520-6882
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The prevalently used immunoassays for fast screening of aftatoxins (AFs) usually cannot meet the requirement for simultaneous determination of total AFs (aflatoxin B1 + aflatoxin B2 + aflatoxin G1 + aflatoxin G2) due to the deficiency of highly group-specific antibodies. This paper describes a two-step chromogenic reaction based method to quantitatively detect total AFs in rice using colorimetric measurement without antibody. In the method, colorless AFs transform into green-colored indophenol products through the reaction with sodium hydroxide and 2,6-dibromoquinone-4-chloroimide (DBQC) successively, allowing selectively determining total AFs up to 3.9 µg/kg over other competitive mycotoxins under optimal conditions by a UV-vis spectrophotometer. In addition, the colorimetric measurement results of the rice samples agree well with that of a standard HPLC method, demonstrating the good reliability and applicability of the method. Uniquely, the method has potential for on-site detection of total AFs in rice when using a nylon membrane-based device.
[Mh] Termos MeSH primário: Aflatoxinas/análise
Colorimetria/métodos
Oryza/química
[Mh] Termos MeSH secundário: Aflatoxinas/química
Indofenol/análogos & derivados
Indofenol/síntese química
Limite de Detecção
Quinonas/química
Hidróxido de Sódio/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Aflatoxins); 0 (Quinones); 500-85-6 (Indophenol); 537-45-1 (2,6-dibromoquinone 4-chlorimide); 55X04QC32I (Sodium Hydroxide)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160304
[St] Status:MEDLINE
[do] DOI:10.1021/acs.analchem.5b04720


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[PMID]:26078173
[Au] Autor:Hashihama F; Kanda J; Tauchi A; Kodama T; Saito H; Furuya K
[Ad] Endereço:Department of Ocean Sciences, Tokyo University of Marine Science and Technology, Konan, Minato, Tokyo 108-8477, Japan. Electronic address: f-hashi@kaiyodai.ac.jp.
[Ti] Título:Liquid waveguide spectrophotometric measurement of nanomolar ammonium in seawater based on the indophenol reaction with o-phenylphenol (OPP).
[So] Source:Talanta;143:374-380, 2015 Oct 01.
[Is] ISSN:1873-3573
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:We describe a highly sensitive colorimetric method for the determination of nanomolar concentrations of ammonium in seawater based on the indophenol reaction with o-phenylphenol [(1,1'-biphenyl)-2-ol, abbreviated as OPP]. OPP is available as non-toxic, stable flaky crystals with no caustic odor and has some advantages over phenol in practical use. The method was established by using a gas-segmented continuous flow analyzer equipped with two types of long path liquid waveguide capillary cell, LWCCs (100 cm and 200 cm) and an UltraPath (200 cm), which have inner diameters of 0.55 mm and 2 mm, respectively. The reagent concentrations, flow rates of the pumping tubes, and reaction path and temperature were determined on the basis of a manual indophenol blue method with OPP (Kanda, Water Res. 29 (1995) 2746-2750). The sample mixed with reagents that form indophenol blue dye was measured at 670 nm. Aged subtropical surface water was used as a blank, a matrix of standards, and the carrier. The detection limits of the analytical systems with a 100 cm LWCC, a 200 cm LWCC, and a 200 cm UltraPath were 6, 4, and 4 nM, respectively. These systems had high precision (<4% at 100 nM) and a linear dynamic range up to 200 nM. Non-linear baseline drift did not occur when using the UltraPath system. This is due to the elimination of cell clogging because of the larger inner diameter of the UltraPath compared to the LWCCs. The UltraPath system is thus more suitable for long-term measurements compared with the LWCC systems. The results of the proposed sensitive colorimetry and a conventional colorimetry for the determination of seawater samples showed no significant difference. The proposed analytical systems were applied to underway surface monitoring and vertical observation in the oligotrophic South Pacific.
[Mh] Termos MeSH primário: Compostos de Amônio/análise
Compostos de Bifenilo/química
Indofenol/química
Água do Mar/análise
[Mh] Termos MeSH secundário: Compostos de Amônio/química
Espectrofotometria/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Ammonium Compounds); 0 (Biphenyl Compounds); 500-85-6 (Indophenol); D343Z75HT8 (2-phenylphenol)
[Em] Mês de entrada:1603
[Cu] Atualização por classe:170911
[Lr] Data última revisão:
170911
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150617
[St] Status:MEDLINE


  3 / 496 MEDLINE  
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[PMID]:25936660
[Au] Autor:Ayyub OB; Behrens AM; Heligman BT; Natoli ME; Ayoub JJ; Cunningham G; Summar M; Kofinas P
[Ad] Endereço:Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, United States.
[Ti] Título:Simple and inexpensive quantification of ammonia in whole blood.
[So] Source:Mol Genet Metab;115(2-3):95-100, 2015 Jun-Jul.
[Is] ISSN:1096-7206
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Quantification of ammonia in whole blood has applications in the diagnosis and management of many hepatic diseases, including cirrhosis and rare urea cycle disorders, amounting to more than 5 million patients in the United States. Current techniques for ammonia measurement suffer from limited range, poor resolution, false positives or large, complex sensor set-ups. Here we demonstrate a technique utilizing inexpensive reagents and simple methods for quantifying ammonia in 100 µL of whole blood. The sensor comprises a modified form of the indophenol reaction, which resists sources of destructive interference in blood, in conjunction with a cation-exchange membrane. The presented sensing scheme is selective against other amine containing molecules such as amino acids and has a shelf life of at least 50 days. Additionally, the resulting system has high sensitivity and allows for the accurate reliable quantification of ammonia in whole human blood samples at a minimum range of 25 to 500 µM, which is clinically for rare hyperammonemic disorders and liver disease. Furthermore, concentrations of 50 and 100 µM ammonia could be reliably discerned with p = 0.0001.
[Mh] Termos MeSH primário: Amônia/sangue
Análise Química do Sangue/métodos
[Mh] Termos MeSH secundário: Amônia/química
Seres Humanos
Hiperamonemia/sangue
Indofenol/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
500-85-6 (Indophenol); 7664-41-7 (Ammonia)
[Em] Mês de entrada:1603
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150505
[St] Status:MEDLINE


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[PMID]:25580842
[Au] Autor:Dong H; Zu X; Zheng P; Zhang D
[Ad] Endereço:Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
[Ti] Título:A rapid enzymatic assay for high-throughput screening of adenosine-producing strains.
[So] Source:Microb Biotechnol;8(2):230-8, 2015 Mar.
[Is] ISSN:1751-7915
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Adenosine is a major local regulator of tissue function and industrially useful as precursor for the production of medicinal nucleoside substances. High-throughput screening of adenosine overproducers is important for industrial microorganism breeding. An enzymatic assay of adenosine was developed by combined adenosine deaminase (ADA) with indophenol method. The ADA catalyzes the cleavage of adenosine to inosine and NH3 , the latter can be accurately determined by indophenol method. The assay system was optimized to deliver a good performance and could tolerate the addition of inorganic salts and many nutrition components to the assay mixtures. Adenosine could be accurately determined by this assay using 96-well microplates. Spike and recovery tests showed that this assay can accurately and reproducibly determine increases in adenosine in fermentation broth without any pretreatment to remove proteins and potentially interfering low-molecular-weight molecules. This assay was also applied to high-throughput screening for high adenosine-producing strains. The high selectivity and accuracy of the ADA assay provides rapid and high-throughput analysis of adenosine in large numbers of samples.
[Mh] Termos MeSH primário: Adenosina/análise
Ensaios Enzimáticos/métodos
Ensaios de Triagem em Larga Escala/métodos
[Mh] Termos MeSH secundário: Adenosina Desaminase/metabolismo
Amônia/metabolismo
Bactérias/metabolismo
Indofenol/metabolismo
Inosina/metabolismo
Reprodutibilidade dos Testes
Coloração e Rotulagem
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
500-85-6 (Indophenol); 5A614L51CT (Inosine); 7664-41-7 (Ammonia); EC 3.5.4.4 (Adenosine Deaminase); K72T3FS567 (Adenosine)
[Em] Mês de entrada:1511
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150113
[St] Status:MEDLINE
[do] DOI:10.1111/1751-7915.12189


  5 / 496 MEDLINE  
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[PMID]:24978902
[Au] Autor:Tarajia M; Salas E; De Waard J; Goodridge A
[Ti] Título:Enzymatic and endpoint methods yield comparable adenosine deaminase activity in pleural fluid samples.
[So] Source:Clin Chem Lab Med;52(12):e297-300, 2014 Dec.
[Is] ISSN:1437-4331
[Cp] País de publicação:Germany
[La] Idioma:eng
[Mh] Termos MeSH primário: Adenosina Desaminase/metabolismo
Tuberculose Pleural/diagnóstico
[Mh] Termos MeSH secundário: Adulto
Amônia/análise
Amônia/química
Biomarcadores/metabolismo
Colorimetria
Ensaios Enzimáticos
Feminino
Seres Humanos
Indofenol/química
Isoenzimas/metabolismo
Masculino
Meia-Idade
Pleura/metabolismo
[Pt] Tipo de publicação:LETTER; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Biomarkers); 0 (Isoenzymes); 500-85-6 (Indophenol); 7664-41-7 (Ammonia); EC 3.5.4.4 (Adenosine Deaminase)
[Em] Mês de entrada:1507
[Cu] Atualização por classe:161018
[Lr] Data última revisão:
161018
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140701
[St] Status:MEDLINE


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[PMID]:24078189
[Au] Autor:Keskin SY; Keskin CS
[Ti] Título:Quantitative determination of glycine in aqueous solution using glutamate dehydrogenase-immobilized glyoxal agarose beads.
[So] Source:Appl Biochem Biotechnol;172(1):289-97, 2014 Jan.
[Is] ISSN:1559-0291
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this study, an enzymatic procedure for the determination of glycine (Gly) was developed by using a column containing immobilized glutamate dehydrogenase (GDH) on glyoxal agarose beads. Ammonia is produced from the enzymatic reactions between Gly and GDH with NAD(+) in phosphate buffer medium. The indophenol blue method was used for ammonia detection based on the spectrophotometric measurements of blue-colored product absorbing at 640 nm. The calibration graph is linear in the range of 0.1-10 mM of Gly concentrations. The effect of pH, temperature, and time interval was studied to find column stability, and also the interference effects of other amino acids was investigated. The interaction between GDH and glyoxal agarose beads was analyzed by Fourier transform infrared (FTIR) spectroscopy. The morphology of the immobilized and non-immobilized agarose beads were characterized by atomic force microscopy (AFM).
[Mh] Termos MeSH primário: Técnicas Biossensoriais/métodos
Enzimas Imobilizadas/química
Glutamato Desidrogenase/química
Glicina/análise
Glioxilatos/química
Microesferas
Sefarose/química
Água/química
[Mh] Termos MeSH secundário: Enzimas Imobilizadas/metabolismo
Glutamato Desidrogenase/metabolismo
Ácido Glutâmico/análise
Ácido Glutâmico/química
Glicina/química
Concentração de Íons de Hidrogênio
Indofenol/química
Soluções
Temperatura Ambiente
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Enzymes, Immobilized); 0 (Glyoxylates); 0 (Solutions); 059QF0KO0R (Water); 105054-62-4 (glyoxyl agarose); 3KX376GY7L (Glutamic Acid); 500-85-6 (Indophenol); 9012-36-6 (Sepharose); EC 1.4.1.2 (Glutamate Dehydrogenase); TE7660XO1C (Glycine)
[Em] Mês de entrada:1410
[Cu] Atualização por classe:140323
[Lr] Data última revisão:
140323
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:131001
[St] Status:MEDLINE


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[PMID]:23809188
[Au] Autor:Celada P; Lladó-Pelfort L; Santana N; Kargieman L; Troyano-Rodriguez E; Riga MS; Artigas F
[Ad] Endereço:Department of Neurochemistry and Neuropharmacology, Institut d'Investigacions Biomèdiques de Barcelona, (IIBB-CSIC), Barcelona, Spain.
[Ti] Título:Disruption of thalamocortical activity in schizophrenia models: relevance to antipsychotic drug action.
[So] Source:Int J Neuropsychopharmacol;16(10):2145-63, 2013 Nov.
[Is] ISSN:1469-5111
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Non-competitive NMDA receptor antagonists are widely used as pharmacological models of schizophrenia due to their ability to evoke the symptoms of the illness. Likewise, serotonergic hallucinogens, acting on 5-HT(2A) receptors, induce perceptual and behavioural alterations possibly related to psychotic symptoms. The neurobiological basis of these alterations is not fully elucidated. Data obtained in recent years revealed that the NMDA receptor antagonist phencyclidine (PCP) and the serotonergic hallucinogen 1-(2,5-dimethoxy-4-iodophenyl-2-aminopropane; DOI) produce a series of common actions in rodent prefrontal cortex (PFC) that may underlie psychotomimetic effects. Hence, both agents markedly disrupt PFC function by altering pyramidal neuron discharge (with an overall increase) and reducing the power of low frequency cortical oscillations (LFCO; < 4 Hz). In parallel, PCP increased c-fos expression in excitatory neurons of various cortical areas, the thalamus and other subcortical structures, such as the amygdala. Electrophysiological studies revealed that PCP altered similarly the function of the centromedial and mediodorsal nuclei of the thalamus, reciprocally connected with PFC, suggesting that its psychotomimetic properties are mediated by an alteration of thalamocortical activity (the effect of DOI was not examined in the thalamus). Interestingly, the observed effects were prevented or reversed by the antipsychotic drugs clozapine and haloperidol, supporting that the disruption of PFC activity is intimately related to the psychotomimetic activity of these agents. Overall, the present experimental model can be successfully used to elucidate the neurobiological basis of schizophrenia symptoms and to examine the potential antipsychotic activity of new drugs in development.
[Mh] Termos MeSH primário: Comportamento Animal
Encéfalo/fisiopatologia
Indofenol/análogos & derivados
Fenciclidina
Córtex Pré-Frontal/fisiopatologia
Esquizofrenia/induzido quimicamente
Psicologia do Esquizofrênico
Núcleos Talâmicos/fisiopatologia
[Mh] Termos MeSH secundário: Animais
Antipsicóticos/farmacologia
Comportamento Animal/efeitos dos fármacos
Encéfalo/efeitos dos fármacos
Encéfalo/metabolismo
Modelos Animais de Doenças
Seres Humanos
Córtex Pré-Frontal/efeitos dos fármacos
Córtex Pré-Frontal/metabolismo
Esquizofrenia/tratamento farmacológico
Esquizofrenia/metabolismo
Esquizofrenia/fisiopatologia
Núcleos Talâmicos/efeitos dos fármacos
Núcleos Talâmicos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; REVIEW
[Nm] Nome de substância:
0 (Antipsychotic Agents); 0 (dimethoxy-4-indophenyl-2-aminopropane); 500-85-6 (Indophenol); J1DOI7UV76 (Phencyclidine)
[Em] Mês de entrada:1407
[Cu] Atualização por classe:161020
[Lr] Data última revisão:
161020
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130702
[St] Status:MEDLINE
[do] DOI:10.1017/S1461145713000643


  8 / 496 MEDLINE  
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[PMID]:23159275
[Au] Autor:Chen J; Gu B; Wu G; Tu H; Si J; Xu Y; Andersson KE
[Ad] Endereço:Department of Urology, Shanghai Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
[Ti] Título:The effect of the 5-HT2A/2C receptor agonist DOI on micturition in rats with chronic spinal cord injury.
[So] Source:J Urol;189(5):1982-8, 2013 May.
[Is] ISSN:1527-3792
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:PURPOSE: We examined the effects of the 5-HT2A/2C receptor agonist DOI on micturition in chronic spinal cord injured rats. MATERIALS AND METHODS: Female Sprague-Dawley® rats were used. Spinal cord injury was produced by transection at the T10 level. A cystometric study was performed 8 to 12 weeks after transection. Cystometrograms were done using urethane anesthesia in all rats. The selective 5-HT2A antagonist ketanserin was administered after each DOI dose-response curve. All drugs were administered intravenously. RESULTS: Compared to controls, spinal cord injured rats had higher bladder capacity and post-void residual urine volume, and lower voiding efficiency. In spinal cord injured rats DOI (0.01 to 0.3 mg/kg) induced significant dose dependent increases in micturition volume and decreases in residual volume, resulting in increased voiding efficiency. Cystometrogram measurements showed a dose dependent increase in high frequency oscillation activity, evident as an increased number of small oscillation per voiding. This correlated with the improved voiding efficiency. Ketanserin (0.1 mg/kg) partially or completely reversed the DOI induced changes. CONCLUSIONS: High frequency oscillation seems to reflect external urethral sphincter burst activity during voiding. Bladder voiding efficiency and high frequency oscillation activity were decreased in spinal cord injured rats. High frequency oscillation activity can be enhanced by 5-HT2A receptor agonism, improving voiding efficiency. To our knowledge it remains to be studied whether these results may have implications for the future treatment of voiding dysfunction in patients with spinal cord injury.
[Mh] Termos MeSH primário: Indofenol/análogos & derivados
Agonistas de Receptores 5-HT2 de Serotonina/farmacologia
Traumatismos da Medula Espinal/fisiopatologia
Micção/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Doença Crônica
Feminino
Indofenol/farmacologia
Ratos
Ratos Sprague-Dawley
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Serotonin 5-HT2 Receptor Agonists); 0 (dimethoxy-4-indophenyl-2-aminopropane); 500-85-6 (Indophenol)
[Em] Mês de entrada:1306
[Cu] Atualização por classe:130418
[Lr] Data última revisão:
130418
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:121120
[St] Status:MEDLINE


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[PMID]:21952887
[Au] Autor:ElNaggar MS; Van Berkel GJ
[Ad] Endereço:Organic and Biological Mass Spectrometry Group, Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6131, USA.
[Ti] Título:Liquid microjunction surface sampling probe fluid dynamics: characterization and application of an analyte plug formation operational mode.
[So] Source:J Am Soc Mass Spectrom;22(10):1737-43, 2011 Oct.
[Is] ISSN:1879-1123
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The recently discovered sample plug formation and injection operational mode of a continuous flow, coaxial tube geometry, liquid microjunction surface sampling probe (LMJ-SSP) was further characterized and applied for concentration and mixing of analyte extracted from multiple areas on a surface and for nanoliter-scale chemical reactions of sampled material. A transparent LMJ-SSP was constructed and colored analytes were used so that the surface sampling process, plug formation, and the chemical reactions could be visually monitored at the sampling end of the probe before being analyzed by mass spectrometry of the injected sample plug. Injection plug peak widths were consistent for plug hold times as long as the 8 min maximum attempted (RSD below 1.5%). Furthermore, integrated injection peak signals were not significantly different for the range of hold times investigated. The ability to extract and completely mix individual samples within a fixed volume at the sampling end of the probe was demonstrated and a linear mass spectral response to the number of equivalent analyte spots sampled was observed. Using the color and mass changing chemical reduction of the redox dye 2,6-dichlorophenol-indophenol with ascorbic acid, the ability to sample, concentrate, and efficiently run reactions within the same plug volume within the probe was demonstrated.
[Mh] Termos MeSH primário: Hidrodinâmica
Espectrometria de Massas por Ionização por Electrospray/métodos
[Mh] Termos MeSH secundário: Ácido Ascórbico/química
Clorofenóis/química
Corantes/química
Desenho de Equipamento
Indofenol/química
Oxirredução
Espectrometria de Massas por Ionização por Electrospray/instrumentação
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Chlorophenols); 0 (Coloring Agents); 500-85-6 (Indophenol); PQ6CK8PD0R (Ascorbic Acid); Q7E9K52W7E (2,6-dichlorophenol)
[Em] Mês de entrada:1112
[Cu] Atualização por classe:171111
[Lr] Data última revisão:
171111
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110929
[St] Status:MEDLINE
[do] DOI:10.1007/s13361-011-0209-6


  10 / 496 MEDLINE  
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[PMID]:21807208
[Au] Autor:Senra-Ferreiro S; Pena-Pereira F; Costas-Mora I; Romero V; Lavilla I; Bendicho C
[Ad] Endereço:Departamento de Química Analítica y Alimentaria, Área de Química Analítica, Facultad de Química, Universidad de Vigo, Vigo, Spain.
[Ti] Título:Ion pair-based liquid-phase microextraction combined with cuvetteless UV-vis micro-spectrophotometry as a miniaturized assay for monitoring ammonia in waters.
[So] Source:Talanta;85(3):1448-52, 2011 Sep 15.
[Is] ISSN:1873-3573
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A miniaturized method based on liquid-phase microextraction (LPME) in combination with microvolume UV-vis spectrophotometry for monitoring ammonia in waters is proposed. The methodology is based on the extraction of the ion pair formed between the blue indophenol obtained according to the Berthelot reaction and a quaternary ammonium salt into a microvolume of organic solvent. Experimental parameters affecting the LPME performance such as type and concentration of the quaternary ammonium ion salt required to form the ion pair, type and volume of extractant solvent, effect of disperser solvent, ionic strength and extraction time, were optimized. A detection limit of 5.0 µg L(-1) ammonia and an enrichment factor of 30 can be attained after a microextraction time of 4 min. The repeatability, expressed as relative standard deviation, was 7.6% (n=7). The proposed method can be successfully applied to the determination of trace amounts of ammonia in several environmental water samples.
[Mh] Termos MeSH primário: Amônia/análise
Amônia/isolamento & purificação
Microextração em Fase Líquida/métodos
Espectrofotometria/métodos
[Mh] Termos MeSH secundário: Amônia/química
Água Potável/análise
Água Doce/análise
Indofenol/química
Íons/química
Águas Minerais/análise
Miniaturização
Nascentes Naturais/análise
Compostos de Amônio Quaternário/química
Reprodutibilidade dos Testes
Abastecimento de Água/análise
Poços de Água/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Drinking Water); 0 (Ions); 0 (Mineral Waters); 0 (Quaternary Ammonium Compounds); 500-85-6 (Indophenol); 7664-41-7 (Ammonia)
[Em] Mês de entrada:1112
[Cu] Atualização por classe:110802
[Lr] Data última revisão:
110802
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110803
[St] Status:MEDLINE
[do] DOI:10.1016/j.talanta.2011.06.030



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