WorldWideScience

Sample records for amines

  1. Amine Functionalized Porous Network

    KAUST Repository

    Eddaoudi, Mohamed

    2015-05-28

    Amine groups can be introduced in porous materials by a direct (one pot) or post-synthetic modification (PSM) process on aldehyde groups, and the resulting porous materials have increased gas affinity.

  2. The economics of amine usage

    International Nuclear Information System (INIS)

    The EPRI computer programm, 'Aminemod', a PWR chemistry model, has been used to compare the technical advantages of the 'advanced' amines, ethanolamine, 1,2 diaminoethane and 5 aminopentanol over morpholine in generating an elevated pH in the moisture separator and the economics of using these amines has been assessed by using an MS Excel spreadsheet in conjunction with Aminemod. The advanced amines are capable of achieving 1 pH unit above neutrality, the EPRI target for prevention of erosion-corrison, at acceptable cost and, compared with 'conventional' amines, at considerably reduced ionic load on the condensate polisher. The exercise demonstrates that it is essential to evaluate the effect of an amine dosing regime on the total operating cost and that it is not possible to prejudge the economic outcome on the basis of an amine's purchase price. (orig.)

  3. Receptors of mammalian trace amines

    OpenAIRE

    Lewin, Anita H.

    2006-01-01

    The discovery of a family of G-protein coupled receptors, some of which bind and are activated by biogenic trace amines, has prompted speculation as to the physiological role of these receptors. Observations associated with the distribution of these trace amine associated receptors (TAARs) suggest that they may be involved in depression, attention-deficit hyperactivity disorder, eating disorders, migraine headaches, and Parkinson's disease. Preliminary in vitro data, obtained using cloned rec...

  4. Biogenic amines in dairy products

    OpenAIRE

    Linares, Daniel M.; Martín, M. Cruz; Ladero Losada, Víctor Manuel; Álvarez González, Miguel Ángel; Fernández García, María

    2011-01-01

    Biogenic amines (BA) are organic, basic, nitrogenous compounds with biological activity, mainly formed by the decarboxylation of amino acids. BA are present in a wide range of foods, including dairy products, and can accumulate in high concentrations. In some cheeses more than 1000 mg of BA have been detected per kilogram of cheese. The consumption of food containing large amounts of these amines can have toxicological consequences. Although there is no specific legislation regarding the BA c...

  5. Amine-Amine Exchange in Aminium-Methanesulfonate Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, Matthew L.; Varner, Mychel E.; Perraud, Veronique M.; Ezell, Michael J.; Wilson, Jacqueline M.; Zelenyuk, Alla; Gerber, Robert B.; Finlayson-Pitts, Barbara J.

    2014-12-18

    Aerosol particles are ubiquitous in the atmosphere and have been shown to impact the Earth’s climate, reduce visibility, and adversely affect human health. Modeling the evolution of aerosol systems requires an understanding of the species and mechanisms involved in particle growth, including the complex interactions between particle- and gas-phase species. Here we report studies of displacement of amines (methylamine, dimethylamine or trimethylamine) in methanesulfonate salt particles by exposure to a different gas-phase amine, using a single particle mass spectrometer, SPLAT II. The variation of the displacement with the nature of the amine suggests that behavior is dependent on water in or on the particles. Small clusters of methanesulfonic acid with amines are used as a model in quantum chemical calculations to identify key structural elements that are expected to influence water uptake, and hence the efficiency of displacement by gas-phase molecules in the aminium salts. Such molecular-level understanding of the processes affecting the ability of gas-phase amines to displace particle-phase aminium species is important for modeling the growth of particles and their impacts in the atmosphere.

  6. Amine Swingbed Payload Project Management

    Science.gov (United States)

    Hayley, Elizabeth; Curley, Su; Walsh, Mary

    2011-01-01

    The International Space Station (ISS) has been designed as a laboratory for demonstrating technologies in a microgravity environment, benefitting exploration programs by reducing the overall risk of implementing such technologies in new spacecraft. At the beginning of fiscal year 2010, the ISS program manager requested that the amine-based, pressure-swing carbon dioxide and humidity absorption technology (designed by Hamilton Sundstrand, baselined for the ORION Multi-Purpose Crew Vehicle, and tested at the Johnson Space Center in relevant environments, including with humans, since 2005) be developed into a payload for ISS Utilization. In addition to evaluating the amine technology in a flight environment before the first launch of the ORION vehicle, the ISS program wanted to determine the capability of the amine technology to remove carbon dioxide from the ISS cabin environment at the metabolic rate of the full 6-person crew. Because the amine technology vents the absorbed carbon dioxide and water vapor to space vacuum (open loop), additional hardware needed to be developed to minimize the amount of air and water resources lost overboard. Additionally, the payload system would be launched on two separate Space Shuttle flights, with the heart of the payload the swingbed unit itself launching a full year before the remainder of the payload. This paper discusses the project management and challenges of developing the amine swingbed payload in order to accomplish the technology objectives of both the open-loop ORION application as well as the closed-loop ISS application.

  7. Amine Swingbed Payload Project Management

    Science.gov (United States)

    Walsch, Mary; Curley, Su

    2013-01-01

    The International Space Station (ISS) has been designed as a laboratory for demonstrating technologies in a microgravity environment, benefitting exploration programs by reducing the overall risk of implementing such technologies in new spacecraft. At the beginning of fiscal year 2010, the ISS program manager requested that the amine-based, pressure-swing carbon dioxide and humidity absorption technology (designed by Hamilton Sundstrand, baselined for the Orion Multi-Purpose Crew Vehicle, and tested at the Johnson Space Center in relevant environments, including with humans, since 2005) be developed into a payload for ISS Utilization. In addition to evaluating the amine technology in a flight environment before the first launch of the Orion vehicle, the ISS program wanted to determine the capability of the amine technology to remove carbon dioxide from the ISS cabin environment at the metabolic rate of the full 6 ]person crew. Because the amine technology vents the absorbed carbon dioxide and water vapor to space vacuum (open loop), additional hardware needed to be developed to minimize the amount of air and water resources lost overboard. Additionally, the payload system would be launched on two separate Space Shuttle flights, with the heart of the payload-the swingbed unit itself-launching a full year before the remainder of the payload. This paper discusses the project management and challenges of developing the amine swingbed payload in order to accomplish the technology objectives of both the open -loop Orion application as well as the closed-loop ISS application.

  8. Bacterial degradation of monocyclic aromatic amines

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar Arora

    2015-08-01

    Full Text Available Aromatic amines are an important group of industrial chemicals, which are widely used for manufacturing of dyes, pesticides, drugs, pigments, and other industrial products. These compounds have been considered highly toxic to human beings due to their carcinogenic nature. Three groups of aromatic amines have been recognized: monocyclic, polycyclic and heterocyclic aromatic amines. Bacterial degradation of several monocyclic aromatic compounds has been studied in a variety of bacteria, which utilizes monocyclic aromatic amines as their sole source of carbon and energy. Several degradation pathways have been proposed and the related enzymes and genes have also been characterized. Many reviews have been reviewed toxicity of monocyclic aromatic amines; however, there is lack of review on biodegradation of monocyclic aromatic amines. The aim of this review is to summarize bacterial degradation of monocyclic aromatic amines. This review will increase our current understanding of biochemical and molecular basis of bacterial degradation of monocyclic aromatic amines.

  9. Advances in heterocyclic ketene aminals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Recent developments in the study of the reactions of heterocyclic ketene aminals are reviewed with the emphases on regioselective alkylation, acylation and glycosylation reactions, and on the aza-ene reactions with α,β-unsaturated compounds, azo and carbonyl compounds. Reactions with 1,3-dipoles and other reagents to synthesize fused heterocycles are also discussed.

  10. Synthesis and characterization of aminated lignin.

    Science.gov (United States)

    Pan, Hong; Sun, Gang; Zhao, Tao

    2013-08-01

    Amination of lignin can bring reactive amino groups onto the natural polymer and enable it to be employed in engineering materials. The amination reaction was successfully implemented after some of the hydroxyl groups on lignin were epoxidized. The resulted products showed a great quantity of primary amine group and secondary amine group which can be used as curing agents of epoxy resin. The results revealed that several factors including reaction temperature and time, as well as ratios of compounds, could influence the epoxidation and amination reactions. The resulted products were characterized by FT-IR spectra, (1)H NMR, (13)C NMR, element analysis, XPS and thermogravimetry analysis. PMID:23618954

  11. Analysis of heterocyclic aromatic amines.

    Science.gov (United States)

    Murkovic, M

    2007-09-01

    Heterocyclic aromatic amines are formed in protein and amino acid-rich foods at temperatures above 150 degrees C. Of more than twenty heterocyclic aromatic amines identified ten have been shown to have carcinogenic potential. As nutritional hazards, their reliable determination in prepared food, their uptake and elimination in living organisms, including humans, and assessment of associated risks are important food-safety issues. The concentration in foods is normally in the low ng g(-1) range, which poses a challenge to the analytical chemist. Because of the complex nature of food matrixes, clean-up and enrichment of the extracts are also complex, usually involving both cation-exchange (propylsulfonic acid silica gel, PRS) and reversed-phase purification. The application of novel solid-phase extraction cartridges with a wettable apolar phase combined with cation-exchange characteristics simplified this process--both the polar and apolar heterocyclic aromatic amines were recovered in one fraction. Copper phthalocyanine trisulfonate bonded to cotton ("blue cotton") or rayon, and molecular imprinted polymers have also been successfully used for one-step sample clean-up. For analysis of the heterocyclic aromatic amines, liquid chromatography with base-deactivated reversed-phase columns has been used, and, recently, semi-micro and capillary columns have been introduced. The photometric, fluorimetric, or electrochemical detectors used previously have been replaced by mass spectrometers. Increased specificity and sub-ppb sensitivities have been achieved by the use of the selected-reaction-monitoring mode of detection of advanced MS instrumentation, for example the triple quadrupole and Q-TOF instrument combination. Gas chromatography, also with mass-selective detection, has been used for specific applications; the extra derivatization step needed for volatilization has been balanced by the higher chromatographic resolution. PMID:17546447

  12. Biogenic amines in seafood: a review.

    Science.gov (United States)

    Biji, K B; Ravishankar, C N; Venkateswarlu, R; Mohan, C O; Gopal, T K Srinivasa

    2016-05-01

    The biogenic amines are low molecular weight organic bases present normally in the body with biological activity influencing important physiological functions. The physiological functions of these molecules are achieved by very low concentrations in the tissues. However, significantly high amounts of biogenic amines are produced during processing and storage of seafood as a result of microbial contamination and inadequate storage conditions. Microorganisms having decarboxylase enzyme activity convert amino acids to their respective biogenic amines. Biogenic amines in seafood have been implicated as a major causative agent of food borne illness, where intoxication results from the ingestion of foods containing higher amount of biogenic amines. Hence its identification, quantitation and awareness of this food borne toxin are important in relation to food safety and spoilage. The aim of this paper is to review the basic concepts of seafood quality and safety in relation to biogenic amines along with its control measures and future areas for research. PMID:27407186

  13. Film-forming amines in shell boilers

    Energy Technology Data Exchange (ETDEWEB)

    Topp, Holger [Astrium RST Rostock GmbH, Rostock (Germany); Hater, Wolfgang [BK Giulini, Ludwigshafen (Germany); BKG Water Solutions, Ludwigshafen (Germany); Bache, Andre de [BK Giulini, Ludwigshafen (Germany); Kolk, Christian zum [BKG Water Solutions, Ludwigshafen (Germany)

    2012-01-15

    Studies were conducted with the aim of providing answers to important questions concerning the use of film-forming amines in steam generators. Tests were carried out in test steam generators under controlled conditions to study the three following application areas: the influence of film-forming amines on boiling behavior and heat transfer, the influence of film-forming amines on oxidic protective film formation, and the influence of film-forming amines on critical operating conditions. In the experiments water treatment with trisodium phosphate (which is normally used with shell boilers) was compared with treatment with film-forming amines. In all three areas the treatment with film-forming amines achieved comparable or better results than the treatment with trisodium phosphate. (orig.)

  14. BIOGENIC AMINES CONTENT IN DIFFERENT WINE SAMPLES

    OpenAIRE

    Attila Kántor; Miroslava Kačániová; Vendula Pachlová

    2015-01-01

    Twenty-five samples of different Slovak wines before and after filtration were analysed in order to determine the content of eight biogenic amines (tryptamine, phenylalanine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine). The method involves extraction of biogenic amines from wine samples with used dansyl chloride. Ultra-high performance liquid chromatography (UHPLC) was used for determination of biogenic amines equipped with a Rapid Resolution High Definition (RRHD), ...

  15. A ruthenium racemisation catalyst for the synthesis of primary amines from secondary amines.

    Science.gov (United States)

    Pingen, Dennis; Altıntaş, Çiğdem; Rudolf Schaller, Max; Vogt, Dieter

    2016-08-01

    A Ru-based half sandwich complex used in amine and alcohol racemization reactions was found to be active in the splitting of secondary amines to primary amines using NH3. Conversions up to 80% along with very high selectivities were achieved. However, after about 80% conversion the catalyst lost activity. Similar to Shvo's catalyst, the complex might deactivate under the influence of ammonia. It was revealed that not NH3 but mainly the primary amine is responsible for the deactivation. PMID:27321431

  16. Chan-Evans-Lam Amination of Boronic Acid Pinacol (BPin) Esters: Overcoming the Aryl Amine Problem.

    Science.gov (United States)

    Vantourout, Julien C; Law, Robert P; Isidro-Llobet, Albert; Atkinson, Stephen J; Watson, Allan J B

    2016-05-01

    The Chan-Evans-Lam reaction is a valuable C-N bond forming process. However, aryl boronic acid pinacol (BPin) ester reagents can be difficult coupling partners that often deliver low yields, in particular in reactions with aryl amines. Herein, we report effective reaction conditions for the Chan-Evans-Lam amination of aryl BPin with alkyl and aryl amines. A mixed MeCN/EtOH solvent system was found to enable effective C-N bond formation using aryl amines while EtOH is not required for the coupling of alkyl amines. PMID:27045570

  17. Amine degradation and associated problems in the gas treating unit

    Energy Technology Data Exchange (ETDEWEB)

    Baumeister, E.R. [Dow Chemical Co. (United States); Souza, R.C.O [Dow Brasil S.A., Sao Paulo, SP (Brazil)

    2008-07-01

    Amine degradation and associated problems in the amine gas treating unit cannot be completely avoided or eliminated. They can be cost effectively mitigated using a thorough amine management program. Economic and performance benefits realized from an amine management program include several improvements and performance index. Better yields, lower costs, and fewer environmental concerns are some of the additional advantages of using a comprehensive amine management system to help run the amine gas treating unit. (author)

  18. Speaking Personally--with Amin Qazi

    Science.gov (United States)

    Ragan, Lawrence

    2016-01-01

    This article provides an interview with Amin Quazi, the founding chief executive officer of Unizin, a university-owned consortium focused on the emerging digital teaching and learning ecosystem. Amin has a bachelor's degree in chemical engineering from The University of Iowa and a master's degree in business administration from the Carlson School…

  19. Thermodynamics of mixtures containing amines

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)], E-mail: jagl@termo.uva.es; Mozo, Ismael; Garcia de la Fuente, Isaias; Cobos, Jose Carlos [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Riesco, Nicolas [Department of Chemical Engineering, Loughborough University, Loughborough, LE113TU Leicestershire (United Kingdom)

    2008-01-30

    Mixtures with dimethyl or trimethylpyridines and alkane, aromatic compound or 1-alkanol have been examined using different theories: DISQUAC, Flory, the concentration-concentration structure factor, S{sub CC}(0), or the Kirkwood-Buff formalism. DISQUAC represents fairly well the available experimental data, and improves theoretical calculations from Dortmund UNIFAC. Two important effects have been investigated: (i) the effect of increasing the number of methyl groups attached to the aromatic ring of the amine; (ii) the effect of modifying the position of the methyl groups in this ring. The molar excess enthalpy, H{sup E}, and the molar excess volume, V{sup E}, decrease in systems with alkane or methanol as follows: pyridine > 3-methylpyridine > 3,5-dimethylpyridine and pyridine > 2-methylpyridine > 2,4-dimethylpyridine > 2,4,6-trimethylpyridine, which has been attributed to a weakening of the amine-amine interactions in the same sequences. This is in agreement with the relative variation of the effective dipole moment, {mu}-bar, and of the differences between the boiling temperature of a pyridine base and that of the homomorphic alkane. For heptane solutions, the observed H{sup E} variation, H{sup E} (3,5-dimethylpyridine) > H{sup E} (2,4-dimethylpyridine) > H{sup E} (2,6-dimethylpyridine), is explained similarly. Calculations on the basis of the Flory model confirm that orientational effects become weaker in systems with alkane in the order: pyridine > methylpyridine > dimethylpyridine > trimethylpyridine. S{sub CC}(0) calculations show that steric effects increase with the number of CH{sub 3}- groups in the pyridine base, and that the steric effects exerted by methyl groups in positions 2 and 6 are higher than when they are placed in positions 3 and 5. The hydrogen bond energy in methanol mixtures is independent of the pyridine base, and it is estimated to be -35.2 kJ mol{sup -1}. Heterocoordination in these solutions is due in part to size effects. Their

  20. Thermodynamics of mixtures containing amines

    International Nuclear Information System (INIS)

    Mixtures with dimethyl or trimethylpyridines and alkane, aromatic compound or 1-alkanol have been examined using different theories: DISQUAC, Flory, the concentration-concentration structure factor, SCC(0), or the Kirkwood-Buff formalism. DISQUAC represents fairly well the available experimental data, and improves theoretical calculations from Dortmund UNIFAC. Two important effects have been investigated: (i) the effect of increasing the number of methyl groups attached to the aromatic ring of the amine; (ii) the effect of modifying the position of the methyl groups in this ring. The molar excess enthalpy, HE, and the molar excess volume, VE, decrease in systems with alkane or methanol as follows: pyridine > 3-methylpyridine > 3,5-dimethylpyridine and pyridine > 2-methylpyridine > 2,4-dimethylpyridine > 2,4,6-trimethylpyridine, which has been attributed to a weakening of the amine-amine interactions in the same sequences. This is in agreement with the relative variation of the effective dipole moment, μ-bar, and of the differences between the boiling temperature of a pyridine base and that of the homomorphic alkane. For heptane solutions, the observed HE variation, HE (3,5-dimethylpyridine) > HE (2,4-dimethylpyridine) > HE (2,6-dimethylpyridine), is explained similarly. Calculations on the basis of the Flory model confirm that orientational effects become weaker in systems with alkane in the order: pyridine > methylpyridine > dimethylpyridine > trimethylpyridine. SCC(0) calculations show that steric effects increase with the number of CH3- groups in the pyridine base, and that the steric effects exerted by methyl groups in positions 2 and 6 are higher than when they are placed in positions 3 and 5. The hydrogen bond energy in methanol mixtures is independent of the pyridine base, and it is estimated to be -35.2 kJ mol-1. Heterocoordination in these solutions is due in part to size effects. Their structure is nearly random. The values of the local mole fractions

  1. Quantifying amine permeation sources with acid neutralization: calibrations and amines measured in coastal and continental atmospheres

    Directory of Open Access Journals (Sweden)

    N. A. Freshour

    2014-04-01

    Full Text Available An acid titration method for quantifying amine permeation rates was used to calibrate an Ambient pressure Proton transfer Mass Spectrometer (AmPMS that monitors ambient amine compounds. The method involves capturing amines entrained in a N2 flow by bubbling it through an acidified solution (~ 10−5 M HCl, and the amines are quantified via changes in solution pH with time. Home-made permeation tubes had permeation rates (typically tens of pmol s−1 that depended on the type of amine and tubing and on temperature. Calibrations of AmPMS yielded sensitivities for ammonia, methyl amine, dimethyl amine, and trimethyl amine that are close to the sensitivity assuming a gas-kinetic, ion-molecule rate coefficient. The permeation tubes were also designed to deliver a reproducible amount of amine to a flow reactor where nucleation with sulfuric acid was studied. The high proton affinity compound dimethyl sulfoxide (DMSO, linked to oceanic environments, was also studied and AmPMS is highly sensitive to it. AmPMS was deployed recently in two field campaigns and mixing ratios are reported for ammonia, alkyl amines, and DMSO and correlations between these species and with particle formation events are discussed.

  2. biogenic aerosol precursors: volatile amines from agriculture

    Science.gov (United States)

    Kuhn, Uwe; Sintermann, Jörg; Spirig, Christoph; Ammann, Christof; Neftel, Albrecht

    2010-05-01

    Information on the occurrence of volatile biogenic amines in the atmosphere is marginal. This group of N-bearing organic compounds are assumed to be a small, though significant component of the atmospheric N-cycle, but are not accounted for in global assessments due to the scarceness of available data. There is increasing evidence for an important role of biogenic amines in the formation of new particulate matter, as well as for aerosol secondary growth. Volatile amines are ubiquitously formed by biodegradation of organic matter, and agriculture is assumed to dominantly contribute to their atmospheric burden. Here we show that the mixing ratios of volatile amines within livestock buildings scale about 2 orders of magnitude lower than NH3, confirming the few literature data available (e.g., Schade and Crutzen, J. Atm. Chem. 22, 319-346, 1995). Flux measurements after manure application in the field, mixing ratios in the headspace of manure storage pools, and concentrations in distilled manure all indicate major depletion of amines relative to NH3 during manure processing. We conclude that the agricultural source distribution of NH3 and amines is not similar. While for NH3 the spreading of manure in the field dominates agricultural emissions, the direct release from livestock buildings dominates the budget of volatile biogenic amines.

  3. Biogenic amines and radiosensitivity of solitary cells

    International Nuclear Information System (INIS)

    Different stability of cells to ionizing radiation is considered from a position of the ''elevated biochemical radioresistance background'' concept. Experimental evidence presented indicates an important role of endogenic amines (serotonin and histamine) possessing radioprotector properties in the cell radioresistance formation. The concept about their effect as being solely a result of circulatory hypoxia is critically discussed. The experimental results favor the existence of a ''cellular'' component, along with the ''hypoxic'' one, in the mechanism of action of biogenic amines. These compounds can affect the initial stages of peroxide oxidation of lipids, thereby favoring a less intensive oxidation induced by radiation. Biogenic amines can also exert influence on the cyclic nucleotide system

  4. Graphite Oxide and Aromatic Amines : Size Matters

    NARCIS (Netherlands)

    Spyrou, Konstantinos; Calvaresi, Matteo; Diamanti, Evmorfi A. K.; Tsoufis, Theodoros; Gournis, Dimitrios; Rudolf, Petra; Zerbetto, Francesco

    2015-01-01

    Experimental and theoretical studies are performed in order to illuminate, for first time, the intercalation mechanism of polycyclic aromatic molecules into graphite oxide. Two representative molecules of this family, aniline and naphthalene amine are investigated. After intercalation, aniline molec

  5. Aromatic amines sources, environmental impact and remediation

    OpenAIRE

    Pereira, Luciana; Mondal, P. K.; Alves, M. M.

    2015-01-01

    Aromatic amines are widely used industrial chemicals as their major sources in the environment include several chemical industry sectors such as oil refining, synthetic polymers, dyes, adhesives, rubbers, perfume, pharmaceuticals, pesticides and explosives. They result also from diesel exhaust, combustion of wood chips and rubber and tobacco smoke. Some types of aromatic amines are generated during cooking, special grilled meat and fish, as well. The intensive use and production of these comp...

  6. Biogenic amines in raw and processed seafood

    OpenAIRE

    Pierina eVisciano; Maria eSchirone; Rosanna eTofalo; Giovanna eSuzzi

    2012-01-01

    The presence of biogenic amines in raw and processed seafood, associated with either time/temperature conditions or food technologies is discussed in the present paper from a safety and prevention point of view. In particular, storage temperature, handling practices, presence of microbial populations with decarboxylase activity and availability of free amino acids are considered the most important factors affecting the production of biogenic amines in raw seafood. On the other hand, some foo...

  7. Enhancing amine terminals in an amine-deprived collagen matrix.

    LENUS (Irish Health Repository)

    Tiong, William H C

    2008-10-21

    Collagen, though widely used as a core biomaterial in many clinical applications, is often limited by its rapid degradability which prevents full exploitation of its potential in vivo. Polyamidoamine (PAMAM) dendrimer, a highly branched macromolecule, possesses versatile multiterminal amine surface groups that enable them to be tethered to collagen molecules and enhance their potential. In this study, we hypothesized that incorporation of PAMAM dendrimer in a collagen matrix through cross-linking will result in a durable, cross-linked collagen biomaterial with free -NH 2 groups available for further multi-biomolecular tethering. The aim of this study was to assess the physicochemical properties of a G1 PAMAM cross-linked collagen matrix and its cellular sustainability in vitro. Different amounts of G1 PAMAM dendrimer (5 or 10 mg) were integrated into bovine-derived collagen matrices through a cross-linking process, mediated by 5 or 25 mM 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) in 5 mM N-hydroxysuccinimide (NHS) and 50 mM 2-morpholinoethane sulfonic acid buffer at pH 5.5. The physicochemical properties of resultant matrices were investigated with scanning electron microscopy (SEM), collagenase degradation assay, differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectra, and ninhydrin assay. Cellular sustainability of the matrices was assessed with Alamar Blue assay and SEM. There was no significant difference in cellular behavior between the treated and nontreated groups. However, the benefit of incorporating PAMAM in the cross-linking reaction was limited when higher concentrations of either agent were used. These results confirm the hypothesis that PAMAM dendrimer can be incorporated in the collagen cross-linking process in order to modulate the properties of the resulting cross-linked collagen biomaterial with free -NH 2 groups available for multi-biomolecular tethering.

  8. Accurate determination of aldehydes in amine catalysts or amines by 2,4-dinitrophenylhydrazine derivatization.

    Science.gov (United States)

    Barman, Bhajendra N

    2014-01-31

    Carbonyl compounds, specifically aldehydes, present in amine catalysts or amines are determined by reversed-phase liquid chromatography using ultraviolet detection of their corresponding 2,4-dinitrophenylhydrazones. The primary focus has been to establish optimum conditions for determining aldehydes accurately because these add exposure concerns when the amine catalysts are used to manufacture polyurethane products. Concentrations of aldehydes determined by this method are found to vary with the pH of the aqueous amine solution and the derivatization time, the latter being problematic when the derivatization reaction proceeds slowly and not to completion in neutral and basic media. Accurate determination of aldehydes in amines through derivatization can be carried out at an effective solution pH of about 2 and with derivatization time of 20min. Hydrochloric acid has been used for neutralization of an amine. For complete derivatization, it is essential to protonate all nitrogen atoms in the amine. An approach for the determination of an adequate amount of acid needed for complete derivatization has been described. Several 0.2M buffer solutions varying in pH from 4 to 8 have also been used to make amine solutions for carrying out derivatization of aldehydes. These solutions have effective pHs of 10 or higher and provide much lower aldehyde concentrations compared to their true values. Mechanisms for the formation of 2,4-dinitrophenylhydrazones in both acidic and basic media are discussed. PMID:24411140

  9. Synthesis of Bis(hydroxylmethylfurfuryl)amine Monomers from 5-Hydroxymethylfurfural.

    Science.gov (United States)

    Xu, Zhanwei; Yan, Peifang; Liu, Kairui; Wan, Lu; Xu, Wenjuan; Li, Huixiang; Liu, Xiumei; Zhang, Z Conrad

    2016-06-01

    We report the synthesis of bis(hydroxylmethylfurfuryl)amine (BHMFA) from 5-hydroxymethylfurfural (5-HMF) by reacting 5-HMF with primary amines in the presence of homogeneous Ru(II) catalysts having sterically strained ligands. BHMFA is a group of furan-based monomers that offer great potential to form functional biopolymers with tunable properties. A range of primary amines, such as aliphatic and benzyl amines, are readily converted with 5-HMF to form the corresponding BHMFA in good yields. The reaction proceeds through reductive amination of 5-HMF with primary amine to form secondary amine, followed by reductive amination of 5-HMF with in situ generated secondary amine to produce BHMFA. PMID:27151257

  10. CCN activity of aliphatic amine secondary aerosol

    Directory of Open Access Journals (Sweden)

    X. Tang

    2014-01-01

    Full Text Available Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical. The particle composition can contain both secondary organic aerosol (SOA and inorganic salts. The fraction of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN activity. SOA formed from trimethylamine (TMA and butylamine (BA reactions with hydroxyl radical (OH is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ ≤ 0.25. Secondary aerosol formed from the tertiary aliphatic amine (TMA with N2O5 (source of nitrate radical, NO3, contains less volatile compounds than the primary aliphatic amine (BA aerosol. TMA + N2O5 form semi-volatile organics in low RH conditions that have κ ~ 0.20, indicative of slightly soluble organic material. As RH increases, several inorganic amine salts are formed as a result of acid-base reactions. The CCN activity of the humid TMA-N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR ideal mixing rules. Higher CCN activity (κ > 0.3 was also observed for humid BA+N2O5 aerosols compared with dry aerosol (κ ~ 0.2, as a result of the formation of inorganic salts such as NH4NO3 and butylamine nitrate (C4H11N · HNO3. Compared with TMA, BA+N2O5 reactions produce more volatile aerosols. The BA+N2O5 aerosol products under humid experiments were found to be very sensitive to the temperature within the stream-wise continuous flow thermal gradient CCN counter. The CCN counter, when set above a 21 °C temperature difference, evaporates BA+N2O5 aerosol formed at RH ≥ 30%; κ ranges from 0.4 to 0.7 and is dependent on the instrument supersaturation (ss settings. The aerosol behaves non-ideally, hence simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems κ ranges from 0.2 < κ < 0.7. This work indicates that

  11. BIOGENIC AMINES CONTENT IN DIFFERENT WINE SAMPLES

    Directory of Open Access Journals (Sweden)

    Attila Kántor

    2015-02-01

    Full Text Available Twenty-five samples of different Slovak wines before and after filtration were analysed in order to determine the content of eight biogenic amines (tryptamine, phenylalanine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine. The method involves extraction of biogenic amines from wine samples with used dansyl chloride. Ultra-high performance liquid chromatography (UHPLC was used for determination of biogenic amines equipped with a Rapid Resolution High Definition (RRHD, DAD detectors and Extend-C18 LC column (50 mm x 3.0 mm ID, 1.8 μm particle size. In this study the highest level of biogenic amine in all wine samples represent tryptamine (TRM with the highest content 170.9±5.3 mg/L in Pinot Blanc wine. Phenylalanine (PHE cadaverine (CAD, histamine (HIS and spermidine (SPD were not detected in all wines; mainly SPD was not detected in 16 wines, HIS not detected in 14 wines, PHE and CAD not detected in 2 wines. Tyramine (TYR, spermine (SPN and putrescine (PUT were detected in all wines, but PUT and SPN in very low concentration. The worst wine samples with high biogenic amine content were Saint Laurent (BF, Pinot Blanc (S and Pinot Noir (AF.

  12. A survey of biogenic amines in vinegars.

    Science.gov (United States)

    Ordóñez, J L; Callejón, R M; Morales, M L; García-Parrilla, M C

    2013-12-01

    This paper reports the determination of biogenic amines by high-performance liquid chromatography (HPLC) and fluorescence detection after derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) in balsamic, apple, and red, white, and Sherry wine vinegars. A solid-phase extraction (SPE) with mixed-mode resins method was used before analysis. The method was successfully validated obtaining adequate values of selectivity, response linearity, precision, accuracy, and low detection and quantification limits. The total content of biogenic amines in vinegars ranged from 23.35 to 1445.2 μg/L, being lower than those reported in wines. Putrescine was the amine that showed the highest concentrations in most samples. Methylamine and phenylethylamine were not determined in any vinegar. Balsamic and "Pedro Ximénez" Sherry vinegars reached the highest amounts of biogenic amines, while apple, white and Sherry wine vinegars had the lowest concentrations. Principal component analysis using the biogenic amines as variables, allowed to separate the different kind of vinegars, excepting red vinegars. PMID:23871015

  13. Biogenic amines in raw and processed seafood

    Directory of Open Access Journals (Sweden)

    Pierina eVisciano

    2012-06-01

    Full Text Available The presence of biogenic amines in raw and processed seafood, associated with either time/temperature conditions or food technologies is discussed in the present paper from a safety and prevention point of view. In particular, storage temperature, handling practices, presence of microbial populations with decarboxylase activity and availability of free amino acids are considered the most important factors affecting the production of biogenic amines in raw seafood. On the other hand, some food technological treatments such as salting, ripening, fermentation or marination can increase the levels of biogenic amines in processed seafood. The consumption of high amount of biogenic amines, above all histamine, can result in food borne poisoning which is a worldwide problem. The European Regulation established as maximum limits for histamine, in fishery products from fish species associated with high histidine amounts, values ranging from 100 to 200 mg/kg, while for products which have undergone enzyme maturation treatment in brine, the aforementioned limits rise to 200 and 400 mg/kg. Preventive measures and emerging methods aiming at controlling the production of biogenic amines are also reported for potential application in seafood industries.

  14. Total synthesis of palau'amine

    OpenAIRE

    Namba, Kosuke; Takeuchi, Kohei; Kaihara, Yukari; Oda, Masataka; Nakayama, Akira; Nakayama, Atsushi; YOSHIDA, Masahiro; Tanino, Keiji

    2015-01-01

    Palau'amine has received a great deal of attention in the past two decades as an attractive synthetic target by virtue of its intriguing molecular architecture and significant immunosuppressive activity. Here we report the total synthesis of palau'amine characterized by the construction of an ABDE tetracyclic ring core including a trans-bicylo[3.3.0]octane skeleton at a middle stage of total synthesis. The ABDE tetracyclic ring core is constructed by a cascade reaction of a cleavage of the N–...

  15. SUICIDAL IDEATION AND BIOGENIC AMINES IN DEPRESSION*

    OpenAIRE

    Palaniappan, V.; V. Ramachandran; Somasundaram, O.

    1983-01-01

    SUMMARY This report is based on the study of 40 depressives in an attempt to explore the possible association between the suicidal ideas and the biogenic amines. The severity of suicidal ideas was measured on Hamilton Depressive Rating Scale and their amine metabolites were measured (MHFG, HVA and 5 HIAA) in urine and C.S.F. It was observed that the level of 5 HIAA, and Serotonin (5 HT) was more related to suicidal ideas and was inversely related. The probable associations between these are d...

  16. Corrosion inhibition of brass by aliphatic amines

    International Nuclear Information System (INIS)

    Aliphatic amines hexylamine (HCA), octylamine (OCA) and decylamine (DCA) have been used as corrosion inhibitors for (70/30) brass in 0.I M HCIO4. The inhibitor efficiency (%P) calculated using weight loss, Tafel extrapolation, linear polarization and impedance methods was found to be in the order DCA> OCA> HCA. These adsorb on brass surface following bockris-swinkels' isotherm. DCA, OCA and HCA displaced 4, 3 and 2 molecules of water from interface respectively. Displacement of water molecules brought a great reorganization of double layer at the interface. These amines during corrosion form complexes with dissolved zinc and copper ions.(Author)

  17. A molecular probe for the optical detection of biogenic amines

    OpenAIRE

    Lee, Boram; Scopelliti, Rosario; Severin, Kay

    2011-01-01

    A coumarin derivative was employed for the detection of biogenic amines in buffered aqueous solution by UV-Vis or fluorescence spectroscopy. Incorporated in a polymeric matrix, the dye can also be used for the optical detection of gaseous amines.

  18. Enantioselective catalytic syntheses of alpha-branched chiral amines

    DEFF Research Database (Denmark)

    Brase, S.; Baumann, T.; Dahmen, S.;

    2007-01-01

    Chiral amines play a pivotal role in fine chemical and natural product syntheses and the design of novel materials.......Chiral amines play a pivotal role in fine chemical and natural product syntheses and the design of novel materials....

  19. Amine synthesis using tandem aza-witting/imine reduction reactions

    OpenAIRE

    Meng, Qi; 孟琪

    2013-01-01

    Nowadays, both secondary and tertiary amines are playing vital roles in modern chemical industry as well as pharmaceutical industry. Various synthetic methods of amines have also been reported due to their promising applications. In this thesis, a simple and widely applicable one-pot aza-Wittig/reduction method is reported for synthesizing both secondary and tertiary amines. Firstly, we focused on tandem aza-Wittig/reduction reactions for synthesizing secondary amines. We noticed that an a...

  20. Factors influencing biogenic amines accumulation in dairy products

    OpenAIRE

    Daniel M. eLinares; Beatriz edel Río; Victor eLadero; Noelia eMartínez; María eFernández; María Cruz eMartín; Miguel A. eAlvarez

    2012-01-01

    Fermented foods are within the food products more often complained of having caused biogenic amines poisoning. Concerning milk-based fermented foods, cheese is the main product likely to contain significant levels of biogenic amines, specially tyramine, histamine and putrescine. Prompted by the increasing awareness of the risks related to dietary uptake of high biogenic amine loads, in this review we report about cheese elaboration and processing technological aspects affecting biogenic amine...

  1. Reductive amination with zinc powder in aqueous media

    OpenAIRE

    Giovenzana, Giovanni B.; Daniela Imperio; Andrea Penoni; Giovanni Palmisano

    2011-01-01

    Zinc powder in aqueous alkaline media was employed to perform reductive amination of aldehydes with primary amines. The corresponding secondary amines were obtained in good yields along with minor amounts of hydrodimerization byproducts. The protocol is a green alternative to the use of complex hydrides in chlorinated or highly flammable solvents.

  2. Reductive amination with zinc powder in aqueous media

    Directory of Open Access Journals (Sweden)

    Giovanni B. Giovenzana

    2011-08-01

    Full Text Available Zinc powder in aqueous alkaline media was employed to perform reductive amination of aldehydes with primary amines. The corresponding secondary amines were obtained in good yields along with minor amounts of hydrodimerization byproducts. The protocol is a green alternative to the use of complex hydrides in chlorinated or highly flammable solvents.

  3. 40 CFR 721.9490 - Coco alklydimethyl amine salts (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Coco alklydimethyl amine salts... Specific Chemical Substances § 721.9490 Coco alklydimethyl amine salts (generic). (a) Chemical substances... coco alkyldimethyl amine salts (PMNs P-98-412/414/415/416/417) are subject to reporting under...

  4. 40 CFR 721.10046 - Polyaromatic amine phosphate (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyaromatic amine phosphate (generic... Specific Chemical Substances § 721.10046 Polyaromatic amine phosphate (generic). (a) Chemical substance and... amine phosphate (PMN P-02-747) is subject to reporting under this section for the significant new...

  5. New adducts of Lapachol with primary amines

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Mirelly D.F.; Litivack-Junior, Jose T.; Antunes, Roberto V.; Silva, Tania M.S.; Camara, Celso A., E-mail: ccelso@dq.ufrpe.b [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil). Dept. de Quimica

    2011-07-01

    New adducts of lapachol with neat primary aliphatic amines were obtained in a solvent-free reaction in good to reasonable yields (52 to 88%), at room temperature. The new compounds containing a phenazine moiety were obtained from suitable functionalized aminoalkyl compounds, including ethanolamine, 3-propanolamine, 2-methoxy-ethylamine, 3-methoxy-propylamine, n-butylamine and 2-phenetylamine. (author)

  6. Role of Amine Functionality for CO2 Chemisorption on Silica.

    Science.gov (United States)

    Hahn, Maximilian W; Jelic, Jelena; Berger, Edith; Reuter, Karsten; Jentys, Andreas; Lercher, Johannes A

    2016-03-01

    The mechanism of CO2 adsorption on primary, secondary, and bibasic aminosilanes synthetically functionalized in porous SiO2 was qualitatively and quantitatively investigated by a combination of IR spectroscopy, thermogravimetry, and quantum mechanical modeling. The mode of CO2 adsorption depends particularly on the nature of the amine group and the spacing between the aminosilanes. Primary amines bonded CO2 preferentially through the formation of intermolecular ammonium carbamates, whereas CO2 was predominantly stabilized as carbamic acid, when interacting with secondary amines. Ammonium carbamate formation requires the transfer of the carbamic acid proton to a second primary amine group to form the ammonium ion and hence two (primary) amine groups are required to bind one CO2 molecule. The higher base strength of secondary amines enables the stabilization of carbamic acid, which is thereby hindered to interact further with nearby amine functions, because their association with Si-OH groups (either protonation or hydrogen bonding) does not allow further stabilization of carbamic acid as carbamate. Steric hindrance of the formation of intermolecular ammonium carbamates leads to higher uptake capacities for secondary amines functionalized in porous SiO2 at higher amine densities. In aminosilanes possessing a primary and a secondary amine group, the secondary amine group tends to be protonated by Si-OH groups and therefore does not substantially interact with CO2. PMID:26700549

  7. Deuterium exchange between hydrofluorocarbons and amines

    International Nuclear Information System (INIS)

    The invention consists of a process for obtaining a compound enriched in deuterium which comprises the known method of exposing a gaseous hydrofluorocarbon to infrared laser radiation of a predetermined frequency to selectively cause a chemical reaction involving hydrofluorocarbon molecules containing deuterium without substantially affecting hydrofluorocarbon molecules not containing deuterium, thereby producing, as reaction products, a compound enriched in deuterium and hydrofluorocarbon depleted in deuterium; combined with a new method, which comprises enriching the deuterium content of the depleted hydrofluorocarbon by contacting the depleted hydrofluorocarbon with an alkali metal amide and an amine having a concentration of deuterium at least that which will yield an increase in deuterium concentration of the hydrofluorocarbon upon equilibration, whereby the amine becomes depleted in deuterium

  8. Thermodynamics of mixtures containing amines: XIII. Application of the ERAS model to cyclic amine + alkane mixtures

    Energy Technology Data Exchange (ETDEWEB)

    González, Juan Antonio, E-mail: jagl@termo.uva.es; Sanz, Luis Felipe; García De La Fuente, Isaías; Cobos, José Carlos

    2013-12-10

    Graphical abstract: - Highlights: • Primary or secondary cyclic amine + alkane mixtures are investigated using ERAS. • ERAS parameters are given. Relatively high X{sub AB} values remark the importance of physical interactions. • ERAS parameters are consistent with those of primary or secondary (linear or aromatic) amines. • H{sub m}{sup E}, V{sub m}{sup E}, and C{sub pm}{sup E} data reveal the existence of physical interactions and structural effects. • ERAS correctly describes H{sub m}{sup E}, V{sub m}{sup E}, C{sub pm}{sup E}, G{sub m}{sup E} and the enthalpy of vaporization of pure amines. - Abstract: Primary or secondary cyclic amine + alkane mixtures have been investigated in the framework of the ERAS (Extended Real Associated Solution) model. The corresponding ERAS parameters are reported. All the amines considered have the same equilibrium constant (K{sub A} = 0.75). Cyclopropylamine, cyclopentylamine, cyclohexylamine and pyrrolidine are characterized by the same enthalpy of self-association (Δh{sub A}{sup *}=−15 kJ mol{sup −1}). Piperidine and hexamethyleneimine show a less negative Δh{sub A}{sup *} value (−13 kJ mol{sup −1}). Experimental data on excess enthalpies, H{sub m}{sup E}, volumes, V{sub m}{sup E}, and isobaric heat capacities, C{sub pm}{sup E}, reveal the existence of physical interactions and structural effects in the studied solutions. The latter lead to values of self-association of pure amines, Δv{sub A}{sup *}, which may depend on the solvent in systems with a given amine. Although the model overestimates the Δh{sub A}{sup *} values, the relatively high values of the physical parameters X{sub AB} remark the importance of physical interactions. ERAS describes correctly the excess functions H{sub m}{sup E}, V{sub m}{sup E}, C{sub pm}{sup E} and G{sub m}{sup E} (molar Gibbs energy), and the enthalpy of vaporization of pure amines. Nevertheless, discrepancies with experimental data are found for the concentration

  9. Biogenic Amines in Raw and Processed Seafood

    OpenAIRE

    Visciano, Pierina; Schirone, Maria; Tofalo, Rosanna; Suzzi, Giovanna

    2012-01-01

    The presence of biogenic amines (BAs) in raw and processed seafood, associated with either time/temperature conditions or food technologies is discussed in the present paper from a safety and prevention point of view. In particular, storage temperature, handling practices, presence of microbial populations with decarboxylase activity and availability of free amino acids are considered the most important factors affecting the production of BAs in raw seafood. On the other hand, some food techn...

  10. Rett syndrome - Stimulation of endogenous biogenic amines

    Science.gov (United States)

    Pelligra, R.; Norton, R. D.; Wilkinson, R.; Leon, H. A.; Matson, W. R.

    1992-01-01

    Transient hypercapnic hyperoxemia was induced in two Rett syndrome children by the administration of a gaseous mixture of 80 percent O2 and 20 percent CO2. Time course studies of neurotransmitters and their metabolites showed an immediate and marked increase in central biogenic amine turnover following inhalation of the gas mixture. The increased turnover of biogenic amines was associated with improved clinical changes. This suggests a coupled relationship and provides further support for an etiological role of neurotransmitter dysfunction in Rett syndrome. In a complementary study, elevation of pulmonary CO2 by application of a simple rebreathing device resulted in improvement of abnormal blood gases and elimination of the Cheyne-Stokes-like respiratory pattern of the Rett syndrome. Near normalization of the EEG occurred when a normal respiratory pattern was imposed by means of a respirator. Taken together, these results lead to the preliminary conclusion that cerebral hypoxemia secondary to abnormal respiratory function may contribute to diminished production of biogenic amines in Rett syndrome.

  11. Biogenic amine metabolism in juvenile neurocardiogenic syncope with dysautonomia

    OpenAIRE

    Butler, Ian J.; Lankford, Jeremy E; Hashmi, Syed Shahrukh; Numan, Mohammed T

    2014-01-01

    Objective Biogenic amine brain levels and their cerebral metabolism are frequently studied by quantitation of biogenic amine metabolites in cerebrospinal fluid (CSF) compared to age-matched controls. There is a paucity of studies in adolescents and young adults investigating the potential role of disordered cerebral biogenic amine metabolism in young patients who have dysautonomia based on abnormal head-up tilt table (HUTT). Methods In a cohort of juvenile patients with neurocardiogenic synco...

  12. Characterization of a novel amine transaminase from Halomonas elongata

    OpenAIRE

    Cerioli, Lorenzo; Planchestainer, Matteo; Cassidy, Jennifer; Tessaro, Davide; Paradisi, Francesca

    2015-01-01

    Chiral amines are indispensable building blocks in the production of biologically active compounds. They are fundamental for the pharmaceutical industry, both as active molecules themselves and as chiral auxiliaries in asymmetric synthesis; however, the available synthetic strategies often present disadvantages. ω-Transaminases (ω-TAs) appear as an attractive alternative by driving the stereoselective amination of prochiral ketones. HEWT is a novel amine transaminase from the moderate halophi...

  13. A regenerable solid amine CO2 concentrator for space station

    Science.gov (United States)

    Boehm, A. M.; Cusick, R. J.

    1982-01-01

    A regenerable solid amine CO2 control system, which employs water vapor for desorption, is being developed for potential use on long duration space missions. During cyclic operation, CO2 is first absorbed from the cabin atmosphere onto the granular amine. Steam is then used to heat the solid amine bed and desorb the CO2. This paper describes the solid amine system operation and application to the Shuttle Orbiter, Manned Space Platform (MSP) and Space Operations Center (SOC). The importance and interplay of system performance parameters are presented together with supporting data and design characteristics.

  14. A Novel Palladium-catalyzed Amination of Aryl Halides with Amines Using rac-P-Phos as the Ligand

    Institute of Scientific and Technical Information of China (English)

    CHEN, Huansheng; WANG, Quanrui; TAO, Fenggang

    2009-01-01

    An efficient palladium-catalyzed amination of aryl halides with amines, using rac-P-Phos as the ancillary ligand and Pd(OAc)2 as the palladium source is developed. The ligand and all of the synthetic intermediates are stable to air and moisture, allowing the easy handling. The catalyst system performed well for a large number of different substrate combinations in 80-110 ℃ to furnish aromatic amines in high yields.

  15. Amine reactivity with charged sulfuric acid clusters

    Directory of Open Access Journals (Sweden)

    B. R. Bzdek

    2011-08-01

    Full Text Available The distribution of charged species produced by electrospray of an ammonium sulfate solution in both positive and negative polarities is examined using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS. Positively-charged ammonium bisulfate cluster composition differs significantly from negatively-charged cluster composition. For positively-charged clusters all sulfuric acid is neutralized to bisulfate, whereas for negatively-charged clusters the degree of sulfuric acid neutralization is cluster size-dependent. With increasing cluster size (and, therefore, a decreasing role of charge, both positively- and negatively-charged cluster compositions converge toward ammonium bisulfate. The reactivity of negatively-charged sulfuric acid-ammonia clusters with dimethylamine and ammonia is also investigated by FTICR-MS. Two series of negatively-charged clusters are investigated: [(HSO4(H2SO4x] and [(NH4x(HSO4x+1(H2SO43]. Dimethylamine substitution for ammonia in [(NH4 x(HSO4 x+1(H2SO43] clusters is nearly collision-limited, and subsequent addition of dimethylamine to neutralize H2SO4 to bisulfate is within one order of magnitude of the substitution rate. Dimethylamine addition to [(HSO4 (H2SO4 x] clusters is either not observed or very slow. The results of this study indicate that amine chemistry will be evident and important only in large ambient negative ions (>m/z 400, whereas amine chemistry may be evident in small ambient positive ions. Addition of ammonia to unneutralized clusters occurs at a rate that is ~2–3 orders of magnitude slower than incorporation of dimethylamine either by substitution or addition

  16. The Multiple Facets of Iodine(III) Compounds in an Unprecedented Catalytic Auto-amination for Chiral Amine Synthesis.

    Science.gov (United States)

    Buendia, Julien; Grelier, Gwendal; Darses, Benjamin; Jarvis, Amanda G; Taran, Frédéric; Dauban, Philippe

    2016-06-20

    Iodine(III) reagents are used in catalytic one-pot reactions, first as both oxidants and substrates, then as cross-coupling partners, to afford chiral polyfunctionalized amines. The strategy relies on an initial catalytic auto C(sp(3) )-H amination of the iodine(III) oxidant, which delivers an amine-derived iodine(I) product that is subsequently used in palladium-catalyzed cross-couplings to afford a variety of useful building blocks with high yields and excellent stereoselectivities. This study demonstrates the concept of self-amination of the hypervalent iodine reagents, which increases the value of the aryl moiety. PMID:27158802

  17. Chemoselective Reductive Amination of Carbonyl Compounds for the Synthesis of Tertiary Amines Using SnCl2·2H2O/PMHS/MeOH.

    Science.gov (United States)

    Nayal, Onkar S; Bhatt, Vinod; Sharma, Sushila; Kumar, Neeraj

    2015-06-01

    Stannous chloride catalyzed chemoselective reductive amination of a variety of carbonyl compounds with aromatic amines has been developed for the synthesis of a diverse range of tertiary amines using inexpensive polymethylhydrosiloxane as reducing agent in methanol. The present method is also applicable for the synthesis of secondary amines including heterocyclic ones. PMID:25938581

  18. Trace Amines and the Trace Amine-Associated Receptor 1: Pharmacology, Neurochemistry and Clinical Implications

    Directory of Open Access Journals (Sweden)

    Yue ePei

    2016-04-01

    Full Text Available Biogenic amines are a collection of endogenous molecules that play pivotal roles as neurotransmitters and hormones. In addition to the classical biogenic amines resulting from decarboxylation of aromatic acids, including dopamine (DA, norepinephrine, epinephrine, serotonin (5-HT and histamine, other biogenic amines, present at much lower concentrations in the central nervous system (CNS, and hence referred to as trace amines (TAs, are now recognized to play significant neurophysiological and behavioural functions. At the turn of the century, the discovery of the trace amine-associated receptor 1 (TAAR1, a phylogenetically conserved G protein-coupled receptor that is responsive to both TAs, such as β-phenylethylamine, octopamine and tyramine, and structurally-related amphetamines, unveiled mechanisms of action for TAs other than interference with aminergic pathways, laying the foundations for deciphering the functional significance of TAs and its mammalian CNS receptor, TAAR1. Although its molecular interactions and downstream targets have not been fully elucidated, TAAR1 activation triggers accumulation of intracellular cAMP, modulates PKA and PKC signalling and interferes with the β-arrestin2-dependent pathway via G protein-independent mechanisms. TAAR1 is uniquely positioned to exert direct control over DA and 5-HT neuronal firing and release, which has profound implications for understanding the pathophysiology of, and therefore designing more efficacious therapeutic interventions for, a range of neuropsychiatric disorders that involve aminergic dysregulation, including Parkinson’s disease, schizophrenia, mood disorders and addiction. Indeed, the recent development of novel pharmacological tools targeting TAAR1 has uncovered the remarkable potential of TAAR1-based medications as new generation pharmacotherapies in neuropsychiatry. This review summarizes recent developments in the study of TAs and TAAR1, their intricate neurochemistry and

  19. Trace Amines and the Trace Amine-Associated Receptor 1: Pharmacology, Neurochemistry, and Clinical Implications.

    Science.gov (United States)

    Pei, Yue; Asif-Malik, Aman; Canales, Juan J

    2016-01-01

    Biogenic amines are a collection of endogenous molecules that play pivotal roles as neurotransmitters and hormones. In addition to the "classical" biogenic amines resulting from decarboxylation of aromatic acids, including dopamine (DA), norepinephrine, epinephrine, serotonin (5-HT), and histamine, other biogenic amines, present at much lower concentrations in the central nervous system (CNS), and hence referred to as "trace" amines (TAs), are now recognized to play significant neurophysiological and behavioral functions. At the turn of the century, the discovery of the trace amine-associated receptor 1 (TAAR1), a phylogenetically conserved G protein-coupled receptor that is responsive to both TAs, such as β-phenylethylamine, octopamine, and tyramine, and structurally-related amphetamines, unveiled mechanisms of action for TAs other than interference with aminergic pathways, laying the foundations for deciphering the functional significance of TAs and its mammalian CNS receptor, TAAR1. Although, its molecular interactions and downstream targets have not been fully elucidated, TAAR1 activation triggers accumulation of intracellular cAMP, modulates PKA and PKC signaling and interferes with the β-arrestin2-dependent pathway via G protein-independent mechanisms. TAAR1 is uniquely positioned to exert direct control over DA and 5-HT neuronal firing and release, which has profound implications for understanding the pathophysiology of, and therefore designing more efficacious therapeutic interventions for, a range of neuropsychiatric disorders that involve aminergic dysregulation, including Parkinson's disease, schizophrenia, mood disorders, and addiction. Indeed, the recent development of novel pharmacological tools targeting TAAR1 has uncovered the remarkable potential of TAAR1-based medications as new generation pharmacotherapies in neuropsychiatry. This review summarizes recent developments in the study of TAs and TAAR1, their intricate neurochemistry and

  20. Denitration of Uranyl Nitrate Using Tridodecyl Amine

    International Nuclear Information System (INIS)

    Nitrate extraction from uranyl nitrate using extractant tridodecyl amine and paraffin has been carried out. The aim of this research was to prepare uranyl nitrate with low nitrate content (acid deficiency uranyl nitrate/ADUN). ADUN is a raw material for making kernels uranium oxide in a spherical from which cannot easily be broken/cracked. This ADUN was prepared by extracting nitric acid in uranyl nitrate solution with tridodecyl amine (TDA) and paraffin. Nitric acid in uranyl nitrate solution moved into organic phase due to the complex formation with TDA. The aqueous phase was ADUN, it was than analyzed its nitric and uranium contents using titration method. Tree variables were observed, i.e. uranium contents (80-125 g/l), process temperature (50-100 oC) and TDA/Nitrate molar ratio (0.5-1). Experiment results showed that optimum condition accurate at uranium content of 100 g/l, temperature extraction 60-70 oC and TDA to Nitrate molar ratio 0.75-0.80 with an efficiency of 77 %. (author)

  1. Reducing tube bundle deposition using alternative amines

    International Nuclear Information System (INIS)

    Particle deposition rates were measured in a high-temperature loop for magnetite and hematite depositing onto Inconel-600 under flow-boiling conditions with pH controlled, using one of the following amines: morpholine, ammonia, ethanolamine, or dimethylamine. Hematite particles deposited at rates 10 times greater than those measured for magnetite although the hematite deposition rate dropped when the loop was operated under reducing conditions. The magnetite deposition rate was influenced by the amine used to control the pH, with the relative rate decreasing in the following series: morpholine (1) : ethanolamine (0.72) : ammonia (0.51) dimethylamine (0.25). These trends in deposition rate are discussed in terms of the surface chemistry of the corrosion products. Deposition rates for both magnetite and hematite increased significantly once the mixture quality exceeded about 0.3, which may be related to a change in the heat-transfer mechanism from nucleate boiling to 2-phase forced-convection through a thin film. (author)

  2. Biogenic amines in submicron marine aerosol (Invited)

    Science.gov (United States)

    Facchini, M.

    2010-12-01

    Ammonium salts of dimethyl and diethyl amine (DMA+ and DEA+) have been detected in size segregated marine samples collected in the North Atlantic over open ocean and at a coastal site. DMA+ and DEA+ peak in the accumulation mode range while very low concentration, close to detection limit, are observed in the coarse size fractions, as well as in sea spray aerosol artificially generated in the laboratory using sea water. These results indicate a secondary formation pathway. DMA+ and DEA+ represent up to 20% of secondary organic aerosol (SOA) in our samples , and to our knowledge they are the most abundant organic species besides MSA ever detected in clean marine aerosol . Maximum concentrations have been observed during spring and summer when the biological activity is high and in clean marine air masses, thus indicating biogenic sources. Total organic nitrogen (ON) concentration also peaks in the accumulation mode range and represents in our samples a fraction from 32 to 54 % of the total SOA. Ammonium salt formation from biogenic amines might be an important source of marine SOA and atmospheric nitrogen at the global scale with a seasonal variation connected to the oceanic biological productivity and an atmospheric cycle parallel to that of the organosulfur species.

  3. Reducing tube bundle deposition with alternative amines

    International Nuclear Information System (INIS)

    Particle deposition rates have been measured in a high-temperature loop for magnetite and hematite depositing onto Inconel-600 under flow-boiling conditions with pH controlled using one of the following amines: morpholine, ammonia, ethanolamine, or dimethylamine. Hematite particles deposited at rates an order of magnitude greater than those measured for magnetite, although the hematite deposition rate dropped when the loop was operated under reducing conditions. The magnetite deposition rate was influenced by the amine used to control the pH, with the relative rate decreasing in the following series: morpholine (1) : ethanolamine (0.72) ammonia (0.51) : dimethylamine (0.25). These trends in deposition rate are discussed in terms of the surface chemistry of the corrosion products. Deposition rates for both magnetite and hematite increased significantly once the mixture quality exceeded about 0.3, which may be related to a change in the heat transfer mechanism from nucleate boiling to two-phase forced convection through a thin film. (author)

  4. Thermodynamics of organic mixtures containing amines

    International Nuclear Information System (INIS)

    Binary mixtures containing pyridine (PY), or 2-methylpyridine (2MPY) or 3-methylpyridine (3MPY) or 4-methylpyridine (4MPY) and an organic solvent as benzene, toluene, alkane, or 1-alkanol are investigated in the framework of DISQUAC. The corresponding interaction parameters are reported. The model describes accurately a whole set of thermodynamic properties: vapor-liquid equilibria (VLE), liquid-liquid equilibria (LLE), solid-liquid equilibria (SLE), molar excess Gibbs energies (GE), molar excess enthalpies (HE), molar excess heat capacities at constant pressure (CPE) and the concentration-concentration structure factor (SCC(0)). It is remarkable that DISQUAC correctly predicts the W-shaped curve of the CPE of the pyridine + n-hexadecane system. The model can be applied successfully to mixtures with strong positive or negative deviations from the Raoult's law. DISQUAC improves the theoretical results from UNIFAC (Dortmund version). The replacement of pyridine by a methylpyridine leads to a weakening of the amine-amine interactions, ascribed to the steric effect caused by the methyl group attached to the aromatic ring. This explains that for a given solvent (alkane, 1-alkanol) HE(pyridine)>HE(methylpyridine)

  5. Thermodynamics of organic mixtures containing amines

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)]. E-mail: jagl@termo.uva.es; Mozo, Ismael [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Fuente, Isaias Garcia de la [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Cobos, Jose Carlos [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)

    2006-02-01

    Binary mixtures containing pyridine (PY), or 2-methylpyridine (2MPY) or 3-methylpyridine (3MPY) or 4-methylpyridine (4MPY) and an organic solvent as benzene, toluene, alkane, or 1-alkanol are investigated in the framework of DISQUAC. The corresponding interaction parameters are reported. The model describes accurately a whole set of thermodynamic properties: vapor-liquid equilibria (VLE), liquid-liquid equilibria (LLE), solid-liquid equilibria (SLE), molar excess Gibbs energies (G{sup E}), molar excess enthalpies (H{sup E}), molar excess heat capacities at constant pressure (C{sub P}{sup E}) and the concentration-concentration structure factor (S{sub CC}(0)). It is remarkable that DISQUAC correctly predicts the W-shaped curve of the C{sub P}{sup E} of the pyridine + n-hexadecane system. The model can be applied successfully to mixtures with strong positive or negative deviations from the Raoult's law. DISQUAC improves the theoretical results from UNIFAC (Dortmund version). The replacement of pyridine by a methylpyridine leads to a weakening of the amine-amine interactions, ascribed to the steric effect caused by the methyl group attached to the aromatic ring. This explains that for a given solvent (alkane, 1-alkanol) H{sup E}(pyridine)>H{sup E}(methylpyridine)

  6. Synthesis of amine functionalized cellulose nanocrystals: optimization and characterization.

    Science.gov (United States)

    Akhlaghi, Seyedeh Parinaz; Zaman, Masuduz; Mohammed, Nishil; Brinatti, César; Batmaz, Rasim; Berry, Richard; Loh, Watson; Tam, Kam Chiu

    2015-05-29

    A simple protocol was used to prepare amine functionalized cellulose nanocrystals (CNC-NH2). In the first step, epichlorohydrin (EPH) was reacted with ammonium hydroxide to produce 2-hydroxy-3-chloro propylamine (HCPA). In the next step, HCPA was grafted to CNC using the etherification reaction in an organic solution media. Various reaction parameters, such as time, temperature, and reactant molar ratio were performed to determine the optimal reaction conditions. The final product (CNC-NH2(T)) was dialyzed for a week. Further purification via centrifugation yielded the sediment (CNC-NH2(P)) and supernatant (POLY-NH2). The presence of amine groups on the surface of modified CNC was confirmed by FTIR and the amine content was determined by potentiometric titration and elemental analysis. A high amine content of 2.2 and 0.6 mmol amine/g was achieved for CNC-NH2(T) and CNC-NH2(P), respectively. Zeta potential measurements confirmed the charge reversal of amine CNC from positive to negative when the pH was increased from 3 to 10. The flocculation of amine functionalized CNC due to its interactions with a negatively charged surfactant namely, sodium dodecyl sulfate (SDS) was investigated at pH 4. It showed promising results for applications, such as in flocculation of fine dispersions in water treatment. This simple and versatile synthetic method to produce high amine content CNC can be used for further conjugation as required for various applications. PMID:25933198

  7. Processing method for drainage-containing ethanol amine

    International Nuclear Information System (INIS)

    Ethanol amine is decomposed by aerobically acting Pseudomonas sp. When drainage contains hydrazine, copper sulfate and hydrogen peroxide are added to the drainage under exposed condition to remove hydrazine as a pretreatment of the decomposing step. With such procedures, ethanol amine in the drainage can be processed efficiently. (T.M.)

  8. Determination of Biogenic Amines with HPLC-APCI-MS

    Science.gov (United States)

    Determination of biogenic amines in fish samples can be used as a quality attribute and are commonly performed using a derivatization step followed by high pressure liquid chromatography (HPLC) and UV detection. Over estimation and misidentification of biogenic amines can occur when interfering comp...

  9. Natural-product synthesis: Stitching together palau'amine

    Science.gov (United States)

    Romo, Daniel

    2010-03-01

    The long-awaited first total synthesis of the structurally intriguing natural product palau'amine has now been achieved. The synthesis features cascade reactions and an 'across ring' stitching of a 'macropalau'amine', and sets the bar for future efforts towards an enantioselective variant.

  10. ELPI+ measurements of aerosol growth in an amine absorption column

    NARCIS (Netherlands)

    Mertens, J.; Brachert, L.; Desagher, D.; Thielens, M.L.; Khakharia, P.M.; Goetheer, E.L.V.; Schaber, K.

    2014-01-01

    Recently, studies have appeared pointing out that aerosols can dominate the total amine emission from amine based PCCC pilot plant scale installations. For the design of countermeasure types (upstream or downstream of the PCCC installation), it is crucial to have an idea of the aerosol size distribu

  11. Secondary organic aerosol formation of primary, secondary and tertiary Amines

    Science.gov (United States)

    Amines have been widely identified in ambient aerosol in both urban and rural environments and they are potential precursors for formation of nitrogen-containing secondary organic aerosols (SOA). However, the role of amines in SOA formation has not been well studied. In this wrok, we use UC-Riversid...

  12. Kinetics of the reaction between carbon dioxide and tertiary amines

    Energy Technology Data Exchange (ETDEWEB)

    Crooks, J.E.; Donnellan, J.P. (King' s Coll., London (England))

    1990-02-16

    The reaction between carbon dioxide and amines is of great technical importance and has been the subject of many investigations. The authors have shown that the reaction for secondary amines in anhydrous ethanol and in aqueous solution is exclusively second-order in amine and that the zwitterion intermediate postulated by Danckwerts is probably of negligible significance in the mechanism. The reaction with tertiary amines has also been studied, but the data are less controversial. In order to complete their studies of the reactions of carbon dioxide with amines, using their conductimetric stopped-flow apparatus, they have studied this reaction for MDEA (methyldiethanolamine, IUPAC name N-methyl-2,2{prime}-iminodiethanol) and TEA (triethanolamine, IUPAC name 2,2{prime},2{double prime}-nitrilotris(ethanol)).

  13. Factors influencing biogenic amines accumulation in dairy products

    Directory of Open Access Journals (Sweden)

    Daniel M. eLinares

    2012-05-01

    Full Text Available Fermented foods are within the food products more often complained of having caused biogenic amines poisoning. Concerning milk-based fermented foods, cheese is the main product likely to contain significant levels of biogenic amines, specially tyramine, histamine and putrescine. Prompted by the increasing awareness of the risks related to dietary uptake of high biogenic amine loads, in this review we report about cheese elaboration and processing technological aspects affecting biogenic amines levels. Synthesis of biogenic amines is possible only when three conditions converge: i availability of the substrate amino acids; ii presence of microorganisms with the appropriate catabolic pathway activated; and iii environmental conditions favorable to the decarboxilation activity. These conditions depend on several factors such as milk treatment (pasteurization, use of starter cultures, NaCl concentration, time and temperature of ripening and preservation, pH… which will be discussed in this chapter.

  14. Spatial relationships between the amine binding site and the copper in plasma amine oxidase

    International Nuclear Information System (INIS)

    Porcine plasma amine oxidase was covalently modified with a series of fluorine containing phenylhydrazine inhibitors. One mole of phenylhydrazine modifies one mole of enzyme at the amine substrate binding site. NMR relaxation measurements on the fluorine nuclei were obtained at two field strengths for each inhibitor-enzyme complex. These measurements were used to calculate the exact distance and spatial orientation between the inhibitor binding site and the copper cofactor. The copper lies in the plane of the aromatic ring of the inhibitor 10.9, 14.3, and 15.5 A from the ortho-, meta-, and para-positions of the ring, respectively. Since the inhibitors react with the active carbonyl cofactor, this defines the spatial relationship between the copper and the active carbonyl cofactor in the enzyme

  15. Synthesis of Boron-Containing Primary Amines

    Directory of Open Access Journals (Sweden)

    Sheng-Hsuan Chung

    2013-10-01

    Full Text Available In this study, boron-containing primary amines were synthesized for use as building blocks in the study of peptoids. In the first step, Gabriel synthesis conditions were modified to enable the construction of seven different aminomethylphenyl boronate esters in good to excellent yields. These compounds were further utilized to build peptoid analogs via an Ugi four-component reaction (Ugi-4CR under microwave irradiation. The prepared Ugi-4CR boronate esters were then successfully converted to the corresponding boronic acids. Finally, the peptoid structures were successfully modified by cross-coupling to aryl/heteroaryl chlorides via a palladium-mediated Suzuki coupling reaction to yield the corresponding derivatives in moderate to good yields.

  16. Electrochemical characterization of aminated acrylic conducting polymer

    International Nuclear Information System (INIS)

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study

  17. Electrochemical characterization of aminated acrylic conducting polymer

    Science.gov (United States)

    Rashid, Norma Mohammad; Heng, Lee Yook; Ling, Tan Ling

    2015-09-01

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study.

  18. Electrochemical characterization of aminated acrylic conducting polymer

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Norma Mohammad [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Heng, Lee Yook [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Southeast Asia Disaster Prevention Research Initiative, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Ling, Tan Ling [Southeast Asia Disaster Prevention Research Initiative, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia)

    2015-09-25

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study.

  19. Poly(Amido Amine)s Containing Agmatine and Butanol Side Chains as Efficient Gene Carriers.

    Science.gov (United States)

    Won, Young-Wook; Ankoné, Marc; Engbersen, Johan F J; Feijen, Jan; Kim, Sung Wan

    2016-04-01

    A new type of bioreducible poly(amido amine) copolymer is synthesized by the Michael addition polymerization of cystamine bisacrylamide (CBA) with 4-aminobutylguanidine (agmatine, AGM) and 4-aminobutanol (ABOL). Since the positively charged guanidinium groups of AGM and the hydroxybutyl groups of ABOL in the side chains have shown to improve the overall transfection efficiency of poly(amido amine)s, it is hypothesized that poly(CBA-ABOL/AGM) synthesized at the optimal ratio of both components would result in high transfection efficiency and minimal toxicity. In this study, a series of the poly(CBA-ABOL/AGM) copolymers is synthesized as gene carriers. The polymers are characterized and luciferase transfection efficiencies of the polymers in various cell lines are investigated to select the ideal ratio between AGM and ABOL. The poly(CBA-ABOL/AGM) containing 80% AGM and 20% ABOL has shown the best transfection efficiency with the lowest cytotoxicity, indicating that this polymer is very promising as a potent and nontoxic gene carrier. PMID:26663734

  20. The sugar model: catalysis by amines and amino acid products

    Science.gov (United States)

    Weber, A. L.

    2001-01-01

    Ammonia and amines (including amino acids) were shown to catalyze the formation of sugars from formaldehyde and glycolaldehyde, and the subsequent conversion of sugars to carbonylcontaining products under the conditions studied (pH 5.5 and 50 degrees C). Sterically unhindered primary amines were better catalysts than ammonia, secondary amines, and sterically hindered primary amines (i.e. alpha-aminoisobutyric acid). Reactions catalyzed by primary amines initially consumed formaldehyde and glycolaldehyde about 15-20 times faster than an uncatalyzed control reaction. The amine-catalyzed reactions yielded aldotriose (glyceraldehyde), ketotriose (dihydroxyacetone), aldotetroses (erythrose and threose), ketotetrose (erythrulose), pyruvaldehyde, acetaldehyde, glyoxal, pyruvate, glyoxylate, and several unindentified carbonyl products. The concentrations of the carbonyl products, except pyruvate and ketotetrose, initially increased and then declined during the reaction, indicating their ultimate conversion to other products (like larger sugars or pyruvate). The uncatalyzed control reaction yielded no pyruvate or glyoxylate, and only trace amounts of pyruvaldehyde, acetaldehyde and glyoxal. In the presence of 15 mM catalytic primary amine, such as alanine, the rates of triose and pyruvaldehyde of synthesis were about 15-times and 1200-times faster, respectively, than the uncatalyzed reaction. Since previous studies established that alanine is synthesized from glycolaldehyde and formaldehyde via pyruvaldehyde as its direct precursor, the demonstration that the alanine catalyzes the conversion of glycolaldehyde and formaldehyde to pyruvaldehyde indicates that this synthetic pathway is capable of autocatalysis. The relevance of this synthetic process, named the Sugar Model, to the origin of life is discussed.

  1. Ozone Promotes Chloropicrin Formation by Oxidizing Amines to Nitro Compounds.

    Science.gov (United States)

    McCurry, Daniel L; Quay, Amanda N; Mitch, William A

    2016-02-01

    Chloropicrin formation has been associated with ozonation followed by chlorination, but the reaction pathway and precursors have been poorly characterized. Experiments with methylamine demonstrated that ozonation converts methylamine to nitromethane at ∼100% yield. Subsequent chlorination converts nitromethane to chloropicrin at ∼50% yield under the conditions evaluated. Similarly high yields from other primary amines were limited to those with functional groups on the β-carbon (e.g., the carboxylic acid in glycine) that facilitate carbon-carbon bond cleavage to release nitromethyl anion. Secondary amines featuring these reactive primary amines as functional groups (e.g., secondary N-methylamines) formed chloropicrin at high yields, likely by facile dealkylation to release the primary nitro compound. Chloropicrin yields from tertiary amines were low. Natural water experiments, including derivatization to transform primary and secondary amines to less reactive carbamate functional groups, indicated that primary and secondary amines were the dominant chloropicrin precursors during ozonation/chlorination. Ozonation followed by chlorination of the primary amine side chain of lysine demonstrated low yields (∼0.2%) of chloropicrin, but high yields (∼17%) of dichloronitrolysine, a halonitroalkane structural analogue to chloropicrin. However, chloropicrin yields increased and dichloronitrolysine yields decreased in the absence of hydroxyl radical scavengers, suggesting that future research should characterize the potential occurrence of such halonitroalkane analogues relative to natural radical scavenger (e.g., carbonate) concentrations. PMID:26752338

  2. Amine functionalized nanodiamond promotes cellular adhesion, proliferation and neurite outgrowth

    International Nuclear Information System (INIS)

    In this study, we report the production of amine functionalized nanodiamond. The amine functionalized nanodiamond forms a conformal monolayer on a negatively charged surface produced via plasma polymerization of acrylic acid. Nanodiamond terminated surfaces were studied as substrates for neuronal cell culture. NG108-15 neuroblastoma-glyoma hybrid cells were successfully cultured upon amine functionalized nanodiamond coated surfaces for between 1 and 7 d. Additionally, primary dorsal root ganglion (DRG) neurons and Schwann cells isolated from Wistar rats were also successfully cultured over a period of 21 d illustrating the potential of the coating for applications in the treatment of peripheral nerve injury. (paper)

  3. Study on the Reaction of Benzimidazolium Salt with Amine Compounds

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The addition-hydrolysis reaction of benzimidazolium salt with some mono- andbifunctional amine nucleophiles is reported, and a novel method of biomimetic synthesis forformamides and heterocycle compounds is provided.

  4. Amine reclaiming technologies in post-combustion carbon dioxide capture.

    Science.gov (United States)

    Wang, Tielin; Hovland, Jon; Jens, Klaus J

    2015-01-01

    Amine scrubbing is the most developed technology for carbon dioxide (CO2) capture. Degradation of amine solvents due to the presence of high levels of oxygen and other impurities in flue gas causes increasing costs and deterioration in long term performance, and therefore purification of the solvents is needed to overcome these problems. This review presents the reclaiming of amine solvents used for post combustion CO2 capture (PCC). Thermal reclaiming, ion exchange, and electrodialysis, although principally developed for sour gas sweetening, have also been tested for CO2 capture from flue gas. The three technologies all have their strengths and weaknesses, and further development is needed to reduce energy usage and costs. An expected future trend for amine reclamation is to focus on process integration of the current reclaiming technologies into the PCC process in order to drive down costs. PMID:25597687

  5. Biogenic amines in meat and fermented meat products

    Directory of Open Access Journals (Sweden)

    Joanna Stadnik

    2010-09-01

    Full Text Available Recent trends in food quality and safety promote an increasing search for trace compounds that can affect human health. Biogenic amines belong to this group of substances. They can cause distinctive pharmacological, physiological and toxic effects in organisms. Their amounts are usually increasing as a consequence of the use of poor quality raw materials, during controlled or spontaneous microbial fermentation or in the course of food spoilage. The origin of biogenic amines makes them suitable as chemical indicators of the hygienic quality and freshness of some foods being associated to the degree of food fermentation or degradation. The development of appropriate manufacturing technologies to obtain products free or nearly free from biogenic amines is a challenge for the meat industry. This review briefly summarises current knowledge on the biological implications of biogenic amines on human health and collects data on the factors affecting their formation in meat and fermented meat products.

  6. Amine reclaiming technologies in post-combustion carbon dioxide capture

    Institute of Scientific and Technical Information of China (English)

    Tielin Wang; Jon Hovland; KlauS J.Jens

    2015-01-01

    Amine scrubbing is the most developed technology for carbon dioxide (CO2) capture.Degradation of amine solvents due to the presence of high levels of oxygen and other impurities in flue gas causes increasing costs and deterioration in long term performance,and therefore purification of the solvents is needed to overcome these problems.This review presents the reclaiming of amine solvents used for post combustion CO2 capture (PCC).Thermal reclaiming,ion exchange,and electrodialysis,although principally developed for sour gas sweetening,have also been tested for CO2 capture from flue gas.The three technologies all have their strengths and weaknesses,and further development is needed to reduce energy usage and costs.An expected future trend for amine reclamation is to focus on process integration of the current reclaiming technologies into the PCC process in order to drive down costs.

  7. Two simple amine hydrochlorides from the soft coral Lobophytum strictum

    Digital Repository Service at National Institute of Oceanography (India)

    Parameswaran, P.S.; Naik, C.G.; Das, B.; Kamat, S.Y.

    Two simple amine hydrochlorides, viz., 1-amino-1, 1-dimethyl-3-oxo-butane hydrochloride (1) (Diacetonamine) and 2, 2, 6, 6-tetramethylpiperidone hydrochloride (2) have been isolated from the fraction of the methanolic extract of the soft coral...

  8. FTIR Study of Enhanced Polymeric Blend Membrane with Amines

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-03-01

    Full Text Available In this study, research will be carried out to identify the functional group behavior of glassy and rubbery polymeric blend membrane with amines. Polymeric blend membranes with different blending ratios were prepared and the developed membranes were characterized by FTIR to see the effect of blend ratio on different functional groups. The developed membranes are flat dense sheet membrane of 20% wt/wt. The pure and blend membrane polysulfone, polyethersulfone, polyvinyl acetate with different composition, with 10% methyl diethanol amine, mono ethanol amine, diethanol amine are developed with dimethyl acetamide solvent. Fourier Transform Infrared (FTIR spectroscopy was utilized to study the interaction between two polymers and to analyze the type of bonding present. To observed frequencies were assigned to various mode of vibration in terms of fundamentals and combination. These spectral changes indicated the existence of molecular interaction among the enhanced polymeric blends; highlight the compatible nature among each other.

  9. Brain imaging with radiolabeled amines and other perfusion tracers

    International Nuclear Information System (INIS)

    This paper discusses how emission CT with radiolabeled amines is useful in a number of circumstances. In acute cerebral infarction, the CT scan may be normal for several days after onset of symptoms, whereas the uptake of radiolabeled amines will be altered immediately after the onset of the stroke. Even when the CT scan has become abnormal, the physiologic abnormality may exceed the anatomic abnormality. We may therefore be able to measure the extent of the reversibly ischemic tissue early enough to justify more aggressive therapeutic interventions. Medical and surgical therapies, such as endarterectomy, have been without readily available objective methods to assess their efficacy. Serial measurements of regional cerebral perfusion with radiolabeled amines may provide such a tool. Of equal importance, SPECT imaging with I-123-labeled amines provides a useful screening test to determine which patients with carotid stenosis should be approached first. Iodine-123 IMP imaging may become the method of choice for the diagnosis and evaluation of Alzheimer's disease

  10. Levels of histamine and other biogenic amines in high quality red wines.

    OpenAIRE

    Konakovsky, Viktor; Focke, Margarete; Hoffmann-Sommergruber, Karin; Schmid, Rainer,; Scheiner, Otto; Moser, Peter; Jarisch, Reinhart; Hemmer, Wolfgang

    2011-01-01

    Abstract Biogenic amines in wine may impair sensory wine quality and cause adverse health effects in susceptible individuals. In this study, histamine and other biogenic amines were determined by HPLC after amine derivatization to dansyl chloride conjugates in 100 selected high quality red wines made from seven different cultivars. Amine levels varied considerably between different wines. The most abundant amines were putrescine (median 19.4 mg/L, range 2.9-122), histamine (7.2, 0....

  11. Biogenic amines in dry fermented sausages: a review.

    Science.gov (United States)

    Suzzi, Giovanna; Gardini, Fausto

    2003-11-15

    Biogenic amines are compounds commonly present in living organisms in which they are responsible for many essential functions. They can be naturally present in many foods such as fruits and vegetables, meat, fish, chocolate and milk, but they can also be produced in high amounts by microorganisms through the activity of amino acid decarboxylases. Excessive consumption of these amines can be of health concern because their not equilibrate assumption in human organism can generate different degrees of diseases determined by their action on nervous, gastric and intestinal systems and blood pressure. High microbial counts, which characterise fermented foods, often unavoidably lead to considerable accumulation of biogenic amines, especially tyramine, 2-phenylethylamine, tryptamine, cadaverine, putrescine and histamine. However, great fluctuations of amine content are reported in the same type of product. These differences depend on many variables: the quali-quantitative composition of microbial microflora, the chemico-physical variables, the hygienic procedure adopted during production, and the availability of precursors. Dry fermented sausages are worldwide diffused fermented meat products that can be a source of biogenic amines. Even in the absence of specific rules and regulations regarding the presence of these compounds in sausages and other fermented products, an increasing attention is given to biogenic amines, especially in relation to the higher number of consumers with enhanced sensitivity to biogenic amines determined by the inhibition of the action of amino oxidases, the enzymes involved in the detoxification of these substances. The aim of this paper is to give an overview on the presence of these compounds in dry fermented sausages and to discuss the most important factors influencing their accumulation. These include process and implicit factors as well as the role of starter and nonstarter microflora growing in the different steps of sausage production

  12. Volatile amines as criteria for chemical quality assessment. Seafoodplus Traceability

    OpenAIRE

    Etienne, Monique

    2005-01-01

    Volatile amines are the characteristic molecules responsible for the fishy odour and flavour present in fish several days after the catch and they are commonly used as criteria for assessing the fish quality. The nature and the formation of the volatile amines are discussed. Ammonia is present in freshly caught fish, during chilled storage it is formed by endogenous and bacterial enzymes, it is a poor indicator of fish freshness and cannot be considered as an effective marker of fish spoila...

  13. Factors Influencing Biogenic Amines Accumulation in Dairy Products

    OpenAIRE

    Linares, Daniel M.; del Río, Beatriz; Ladero, Victor; Martínez, Noelia; Fernández, María; Martín, María Cruz; Álvarez, Miguel A.

    2012-01-01

    Fermented foods are among the food products more often complained of having caused episodes of biogenic amines (BA) poisoning. Concerning milk-based fermented foods, cheese is the main product likely to contain potentially harmful levels of BA, specially tyramine, histamine, and putrescine. Prompted by the increasing awareness of the risks related to dietary uptake of high biogenic amine loads, in this review we report all those elaboration and processing technological aspects affecting BA bi...

  14. Factors influencing biogenic amines accumulation in dairy products

    OpenAIRE

    Alvarez, Miguel A.

    2012-01-01

    Fermented foods are among the food products more often complained of having caused episodes of biogenic amines (BA) poisoning. Concerning milk-based fermented foods, cheese is the main product likely to contain potentially harmful levels of BA, specially tyramine, histamine, and putrescine. Prompted by the increasing awareness of the risks related to dietary uptake of high biogenic amine loads, in this review we report all those elaboration and processing technological aspects affecting BA bi...

  15. Quantification of biogenic amines by microchip electrophoresis with chemiluminescence detection

    OpenAIRE

    Zhao, Shulin; Yong HUANG; Shi, Ming; Liu, Yi-Ming

    2009-01-01

    A highly sensitive microchip electrophoresis (MCE) method with chemiluminescence (CL) detection was developed for the determination of biogenic amines including agmatine, epinephrine, dopamine, tyramine, and histamine in human urine samples. To achieve a high assay sensitivity, the targeted analytes were pre-column labeled by a CL tagging reagent, N-(4-aminobutyl)-N-ethylisoluminol (ABEI). ABEI-tagged biogenic amines after MCE separation reacted with hydrogen peroxide in the presence of horse...

  16. Biogenic amines in meat and fermented meat products

    OpenAIRE

    Joanna Stadnik; Zbigniew J. Dolatowski

    2010-01-01

    Recent trends in food quality and safety promote an increasing search for trace compounds that can affect human health. Biogenic amines belong to this group of substances. They can cause distinctive pharmacological, physiological and toxic effects in organisms. Their amounts are usually increasing as a consequence of the use of poor quality raw materials, during controlled or spontaneous microbial fermentation or in the course of food spoilage. The origin of biogenic amines makes them suitabl...

  17. BIOGENIC AMINES CONTENT IN SELECTED WINES DURING WINEMAKING

    OpenAIRE

    Radka Flasarová; Leona Buňková; Barbora Ivičičová; František Buňka; Stanislav Kráčmar

    2012-01-01

    The aim of this study was to describe the development of selected biogenic amines (histamine; tyramine; phenylethylamine; putrescine; agmatine; and cadaverine) during the winemaking in 10 selected species grown in Central Europe in 2008. The analysis was performed using ion-exchange chromatography by the sodium-citrate buffers with the post-column ninhydrin derivatization and photometric detection. A comparison of the content of biogenic amines in red and wine varieties showed that red wines ...

  18. The analysis of biogenic amines by standard and novel methods

    OpenAIRE

    O'Sullivan, Brian

    2000-01-01

    Biologically active amines in cheese and fish arising from metabolic activities of food-borne microorganisms have been implicated as the causative agents in many food poisoning outbreaks. An awareness of amine levels in foods today is therefore important in relation to food spoilage and safety. In recent years there has been increased consumer awareness about food composition and safety and a corresponding increase in regulatory action. The food industry requires reliable and cost effecti...

  19. Aromatic amine dehydrogenase, a second tryptophan tryptophylquinone enzyme.

    OpenAIRE

    Govindaraj, S; Eisenstein, E.; Jones, L. H.; Sanders-Loehr, J; Chistoserdov, A Y; Davidson, V L; Edwards, S. L.

    1994-01-01

    Aromatic amine dehydrogenase (AADH) catalyzes the oxidative deamination of aromatic amines including tyramine and dopamine. AADH is structurally similar to methylamine dehydrogenase (MADH) and possesses the same tryptophan tryptophylquinone (TTQ) prosthetic group. AADH exhibits an alpha 2 beta 2 structure with subunit molecular weights of 39,000 and 18,000 and with a quinone covalently attached to each beta subunit. Neither subunit cross-reacted immunologically with antibodies to the correspo...

  20. Reductive amination in the synthesis of azaheterocycles (review)

    Energy Technology Data Exchange (ETDEWEB)

    Kriven' ko, A.P.; Nikolaeva, T.G.; Kharchenko, V.G.

    1987-10-01

    Methods for obtaining saturated five- and six-membered azaheterocycles based on the use of catalytic intra- and intermolecular hydroamination of dicarbonyl compounds and ketones and amines of the furan series, hydride amination of aldehydes and ketones, and the Leuckart reaction are examined. The authors attempted to thoroughly analyze these reactions as a function of the structures of the starting substances, the character of the reducing agent, and the conditions of the processes and to correlate the literature data published in recent years.

  1. Catalytic Leuckart-Wallach-type reductive amination of ketones.

    Science.gov (United States)

    Kitamura, Masato; Lee, Donghyun; Hayashi, Shinnosuke; Tanaka, Shinji; Yoshimura, Masahiro

    2002-11-29

    A CpRh(III) complex catalyzes reductive amination of ketones using HCOONH(4) at 50-70 degrees C to give the corresponding primary amines in high yields. The reaction is clean and operationally simple and proceeds at a lower temperature and with higher chemoselectivity than the original Leuckart-Wallach reaction. The new method has been applied to the synthesis of alpha-amino acids directly from alpha-keto acids. PMID:12444661

  2. STUDIES ON VINYL POLYMERIZATION WITH INITIATION SYSTEM CONTAINING AMINE DERIVATIVES

    Institute of Scientific and Technical Information of China (English)

    QIU Kunyuan; ZHANG Jingyi; FENG Xinde(S. T. Voong)

    1983-01-01

    Two main types of amine-containing initiation systems were studied in this work. In the case of MMA polymerization initiated by BPO-amine (DMT, DHET, DMA) redox systems, it was found that the polymerization rate and colour stability of the polymer for different amine systems were in the following order: DMT≈DHET>DMA. Accordingly, BPO-DMT and BPO-DHET are effective initiators. In the case of MEMA polymerization by amine (DMT, DHET, DMA) alone, it was found that the polymerization rate and the percentage of conversion for these different amine systems were in the following order: DMT≥DHET>DMA. The polymerization rate and the percentage of conversion also increased with the increase of DMT concentration. From the kinetic investigation the rate equation of Rp=K [DMT]1/2 [MEMA]3/2 was obtained, and the overall activation energy of polymerization was calculated to be 34.3 KJ/mol (8.2 Kcal/mol). Moreover, the polymerization of MEMA in the presence of DMT was strongly inhibited by hydroquinone, indicating the polymerization being free radical in nature. From these results, the mechanism of MEMA polymerization initiated by amine was proposed.

  3. Kinetics of intraventricularly injected trace amines and their deuterated isotopomers

    International Nuclear Information System (INIS)

    Intraventricular injection into the rat brain of four trace amines and a catecholamine resulted in rapid exponential loss of the amines in the first 30 minutes after injection. The half-lives were: phenylethylamine 3.8 min, para-tyramine 5.1 min, meta-tyramine 7.4 min and dopamine 8.0 min. Tryptamine showed a biphasic loss with half-lives of 4.7 min (over the 5 to 10 min period) and 14.1 min (10 to 30 min). The half-lives were substantially increased by deuterium labeling at the alpha carbon position: phenylethylamine 4.8 min, para-tyramine 8.8 min, meta-tyramine 14.1 min, dopamine 13.0 min and tryptamine 6.0 min (5 to 10 min period) and 28.7 min (10 to 20 min). The loss of the amines was reduced by monoamine oxidase inhibition by pargyline hydrochloride and the deuterium isotope effect was abolished. It is noteworthy that the half-life of dopamine was similar to those of the trace amines in this time period and that the trace amine half-lives after i.v. injection was longer than those obtained from measurements of increases of concentrations of endogenous amines after MAOI in vivo and that of dopamine shorter than values calculated from turnover measurements

  4. Detection of azo dyes and aromatic amines in women undergarment.

    Science.gov (United States)

    Nguyen, Thao; Saleh, Mahmoud A

    2016-07-28

    Women are exposed to several chemical additives including azo dyes that exist in textile materials, which are a potential health hazard for consumers. Our objective was to analyze suspected carcinogenic azo dyes and their degradation aromatic amines in women underwear panties using a fast and simple method for quantification. Here, we evaluated 120 different samples of women underwear for their potential release of aromatic amines to the skin. Seventy-four samples yielded low level mixtures of aromatic amines; however eighteen samples were found to produce greater than 200 mg/kg (ppm) of aromatic amines. Azo dyes in these 18 samples were extracted from the fabrics and analyzed by reverse phase thin layer chromatography in tandem with atmospheric pressure chemical ionization mass spectrometry. Eleven azo dyes were identified based on their mass spectral data and the chemical structure of the aromatic amine produced from these samples. We demonstrate that planar chromatography and mass spectrometry can be really helpful in confirming the identity of the azo dyes, offering highly relevant molecular information of the responsible compounds in the fabrics. With the growing concern about the consumer goods, analysis of aromatic amines in garments has become a highly important issue. PMID:27149414

  5. Heterocyclic amines in meat and meat products

    Directory of Open Access Journals (Sweden)

    Aliye BULGAN

    2013-06-01

    Full Text Available Heterocyclic amines (HA are the mutagenic/carcinogenic compounds which generate as a result of cooking of red meat, poultry meat and fish fillets at high temperatures. Up to 20 different HAs were detected and classified in the researches that conducted on these types of meats cooked at high temperatures. HAs are the products of Maillard reactions and the Strecker degredation of main precursors such as creatine/creatinine, aminoacid and the polysaccharides. Many physical and chemical factors effect the formation of HAs. Thus, it was reported by many researchers that utilizing coating and marination processes in addition to using natural and synthetic antioxidants and seasonings-plant extracts were effective on inhibiting/decreasing the formation of HAs. Additionally, boiling/steaming and microwave cooking methodologies were recommended instead of barbecuing, grilling or frying to inhibit/decrease the formation of HAs. The HAs formed in meat and meat products and the factors which have effects on the formation of HAs are presented in this review.

  6. Sorption of mono ethanol amine and mono ethanol aminate of copper(II) and cadmium(II) on hydrated zirconium dioxide

    International Nuclear Information System (INIS)

    The sorption of mono ethanol amine and mono ethanol aminate of copper(II) and cadmium(II) on hydrated zirconium dioxide is studied. Influence of ph of equilibrium solution, nature of central cation and outer-sphere anion on sorption of mono ethanol amine on hydrated zirconium dioxide is considered.

  7. Amine-pillared Nanosheet Adsorbents for CO2 Capture Applications

    Science.gov (United States)

    Jiang, Hui

    Amine-functionalized solid adsorbents have gained attention within the last decade for their application in carbon dioxide capture, due to their many advantages such as low energy cost for regeneration, tunable structure, elimination of corrosion problems, and additional advantages. However, one of the challenges facing this technology is to accomplish both high CO 2 capture capacity along with high CO2 diffusion rates concurrently. Current amine-based solid sorbents such as porous materials similar to SBA-15 have large pores diffusion entering molecules; however, the pores become clogged upon amine inclusion. To meet this challenge, our group's solution involves the creation of a new type of material which we are calling-amino-pillared nanosheet (APN) adsorbents which are generated from layered nanosheet precursors. These materials are being proposed because of their unique lamellar structure which exhibits ability to be modified by organic or inorganic pillars through consecutive swelling and pillaring steps to form large mesoporous interlayer spaces. After the expansion of the layer space through swelling and pillaring, the large pore space can be functionalized with amine groups. This selective functionalization is possible by the choice of amine group introduced. Our choice, large amine molecules, do not access the micropore within each layer; however, either physically or chemically immobilized onto the surface of the mesoporous interlayer space between each layer. The final goal of the research is to investigate the ability to prepare APN adsorbents from a model nanoporous layered materials including nanosheets precursor material MCM-22(P) and nanoporous layered silicate material AMH-3. MCM-22(P) contains 2-dimensional porous channels, 6 membered rings (MB) openings perpendicular to the layers and 10 MB channels in the plane of the layers. However, the transport limiting openings (6 MB) to the layers is smaller than CO2 gas molecules. In contrast, AMH-3 has

  8. Mutagenic activity and heterocyclic amine content of the human diet

    Energy Technology Data Exchange (ETDEWEB)

    Knize, M.G.; Dolbeare, F.A.; Cunningham, P.L.; Felton, J.S.

    1993-01-15

    The mutagenic activity and the mass amount of heterocyclic amines responsible for the mutagenic activity have been measured in some cooked foods. Cooked meats are the predominant source of mutagenic activity in the diet with values ranging from 0 to 10,000 revertants per gram reported in the Ames/Salmonelia test with strain TA98. Several heterocyclic amines are present and have been quantified using solid-phase extraction followed by HPLC. Frying at higher temperatures and for longer times produces the greatest mutagenic response, and concomitantly, the largest amounts of heterocyclic amines. Most of the mutagenic activity in fried meat samples can be accounted for by MelQx, DiMelQx and IQ, although other heterocylic amines are present and PHIP mutagenic activity becomes significant at higher temperatures. Non-meat products such as baked breads can also form significant mutagenic activity, particularly when overcooked. Commercially prepared hamburgers made from meat substitutes such as tofu, wheat gluten or tempeh and fried at 210{degrees}C have up to 10% of the mutagenic activity of a fried beef patty cooked under the same conditions. When detected, amounts of heterocyclic amines in fried beef patties range from a total of 0.35 ng/g for commercial beef hamburgers to 142 ng/g for a beef patty cooked over a barbecue. Dietary intake is expected to have a large range, from less than one microgram per day to over 50 micrograms per day based on current knowledge of known heterocyclic amine chemicals and heterocyclic amine-containing foods.

  9. Secondary aerosol formation from atmospheric reactions of aliphatic amines

    Directory of Open Access Journals (Sweden)

    S. M. Murphy

    2007-01-01

    Full Text Available Although aliphatic amines have been detected in both urban and rural atmospheric aerosols, little is known about the chemistry leading to particle formation or the potential aerosol yields from reactions of gas-phase amines. We present here the first systematic study of aerosol formation from the atmospheric reactions of amines. Based on laboratory chamber experiments and theoretical calculations, we evaluate aerosol formation from reaction of OH, ozone, and nitric acid with trimethylamine, methylamine, triethylamine, diethylamine, ethylamine, and ethanolamine. Entropies of formation for alkylammonium nitrate salts are estimated by molecular dynamics calculations enabling us to estimate equilibrium constants for the reactions of amines with nitric acid. Though subject to significant uncertainty, the calculated dissociation equilibrium constant for diethylammonium nitrate is found to be sufficiently small to allow for its atmospheric formation, even in the presence of ammonia which competes for available nitric acid. Experimental chamber studies indicate that the dissociation equilibrium constant for triethylammonium nitrate is of the same order of magnitude as that for ammonium nitrate. All amines studied form aerosol when photooxidized in the presence of NOx with the majority of the aerosol mass present at the peak of aerosol growth consisting of aminium (R3NH+ nitrate salts, which repartition back to the gas phase as the parent amine is consumed. Only the two tertiary amines studied, trimethylamine and triethylamine, are found to form significant non-salt organic aerosol when oxidized by OH or ozone; calculated organic mass yields for the experiments conducted are similar for ozonolysis (15% and 5% respectively and photooxidation (23% and 8% respectively. The non-salt organic aerosol formed appears to be more stable than the nitrate salts and does not quickly repartition back to the gas phase.

  10. Biogenic amines in Italian Pecorino cheese

    Directory of Open Access Journals (Sweden)

    Maria eSchirone

    2012-05-01

    Full Text Available The quality of distinctive artisanal cheeses is closely associated with the territory of production and its traditions. Pedoclimatic characteristics, genetic autochthonous variations and anthropic components create an environment so specific that it would be extremely difficult to reproduce elsewhere. Pecorino cheese is included in this sector of the market and is widely diffused in Italy (approximately 53.727t of production. Pecorino is a common name given to indicate Italian cheeses made exclusively from pure ewes' milk characterized by a high content of fat matter and it is mainly produced in the middle and south of Italy by traditional procedures from raw or thermized milk. The microbiota plays a major role in the development of the organoleptic characteristics of the cheese but it can also be responsible for the accumulation of undesirable substances, such as biogenic amines (BA. Several factors can contribute to the qualitative and quantitative profiles of BA’s in Pecorino cheese such as environmental hygienic conditions, pH, salt concentration, aw, fat content, pasteurization of milk, decarboxylase microorganisms, starter cultures, temperature and time of ripening, storage, part of the cheese (core, edge and the presence of cofactor. Generally, the total content of BA’s can range from about 100-2400 mg/kg, with a prevalence of toxicologically important BA’s, tyramine and histamine. The presence of BA in Pecorino cheeses is becoming increasingly important to consumers and cheese-maker alike, due to the potential threats of toxicity to humans and consequent trade implications.

  11. The Potential of the Yeast Debaryomyces hansenii H525 to Degrade Biogenic Amines in Food

    Directory of Open Access Journals (Sweden)

    Mathias Bäumlisberger

    2015-11-01

    Full Text Available Twenty-six yeasts from different genera were investigated for their ability to metabolize biogenic amines. About half of the yeast strains produced one or more different biogenic amines, but some strains of Debaryomyces hansenii and Yarrowia lipolytica were also able to degrade such compounds. The most effective strain D. hanseniii H525 metabolized a broad spectrum of biogenic amines by growing and resting cells. Degradation of biogenic amines by this yeast isolate could be attributed to a peroxisomal amine oxidase activity. Strain H525 may be useful as a starter culture to reduce biogenic amines in fermented food.

  12. Polycyclic amines as chloroquine resistance modulating agents in Plasmodium falciparum.

    Science.gov (United States)

    Joubert, Jacques; Kapp, Erika; Taylor, Dale; Smith, Peter J; Malan, Sarel F

    2016-02-15

    Pentacycloundecylamines (PCUs) and adamantane amines, such as NGP1-01 (1) and amantadine, have shown significant channel blocking activities. They are postulated to act as chemosensitizers and circumvent the resistance of the plasmodia parasite against chloroquine (CQ) by inhibiting the p-glycoprotein efflux pump and enabling the accumulation of CQ inside the parasite digestive vacuole. Twelve polycyclic amines containing either a PCU or adamantane amine moiety conjugated to different aromatic functionalities through various tethered linkers were selected based on their channel blocking abilities and evaluated as potential chemosensitizers. Compounds 2, 4, 5 and 10 showed significant voltage-gated calcium channel (VGCC) blocking ability (IC50=0.27-35 μM) and were able to alter the CQ IC50 in differing degrees (45-81%) in the multidrug resistant Plasmodium falciparum Dd2 isolate. Among them, the PCU-dansyl amine compound (4) displayed the best potential to act as a chemosensitizer against the Dd2 strain at a 1 μM concentration (RMI=0.19) while displaying moderate antiplasmodial activity (Dd2 IC50=6.25 μM) and low in vitro cytotoxicity against a mammalian cell line (CHO, IC50=119 μM). Compounds 2 and 10 also showed some promising chemosensitizing abilities (RMI=0.36 and 0.35 respectively). A direct correlation was found between the VGCC blocking ability of these polycyclic amines and their capacity to act as CQ resistance modulating agents. PMID:26832222

  13. A Metal and Base-Free Chemoselective Primary Amination of Boronic Acids Using Cyanamidyl/Arylcyanamidyl Radical as Aminating Species: Synthesis and Mechanistic Studies by Density Functional Theory.

    Science.gov (United States)

    Chatterjee, Nachiketa; Arfeen, Minhajul; Bharatam, Prasad V; Goswami, Avijit

    2016-06-17

    An efficient, metal and base-free, chemoselective synthesis of aryl-, heteroaryl-, and alkyl primary amines from the corresponding boronic acids has been achieved at ambient temperature mediated by [bis(trifluoroacetoxy)iodo]benzene (PIFA) and N-bromosuccinimide (NBS) using cyanamidyl/arylcyanamidyl radicals as the aminating species. The primary amine compounds were initially obtained as their corresponding ammonium trifluoroacetate salts which, on treatment with aq NaOH, provide the free amines. Finally, the primary amines were isolated through column chromatography over silica-gel using hexane-EtOAc solvent system as the eluent. The reactions are sufficiently fast, completing within 1 h. Quantum chemical calculations in combination with experimental observations validate that the ipso amination of substituted boronic acids involves the formation of cyanamidyl/arylcyanamidyl radical, followed by regiospecific interaction of its nitrile-N center with boron atom of the boronic acids, leading to chemoselective primary amination. PMID:27182931

  14. An epidemiologic approach to studying heterocyclic amines.

    Science.gov (United States)

    Sinha, Rashmi

    2002-09-30

    Diets containing substantial amounts of red meat may increase the risk of colorectal, pancreatic, breast, prostate, and renal cancer. The association with red meat intake may be due to a combination of factors, such as content of fat, protein, and iron, and/or meat preparation (e.g. cooking or preserving methods). Laboratory results have shown that meats cooked at high temperatures contain heterocyclic amines (HCAs) known to be mutagenic and carcinogenic in animals. Many older epidemiologic studies of colon cancer using surrogates for HCA exposure from meat (for example, doneness level, surface browning, frying, intake of gravy) have produced suggestive but inconsistent results. These discrepancies may have resulted in part from having used dietary questionnaires that combined meat-cooking practices in ways that made the intake of HCAs difficult to estimate. Thus, over the last decade we have taken a multidisciplinary approach to investigating whether the association with red meat intake can be explained by meat-cooking practices that produce mutagens/carcinogens. To estimate intake, a database for HCAs have been developed and used in conjunction with a validated meat-cooking food frequency questionnaire (FFQ). To develop biological markers of internal exposure, a metabolic study was conducted where subjects consumed controlled amounts of meat cooked at low and high temperatures. The role of meat type, cooking methods, doneness levels, and meat-cooking mutagens were examined in case-control studies of colorectal adenomas, lung, and breast cancers using both questionnaire information and biomarkers. In a case-control study of colorectal adenomas, an increased risk was associated with a high intake of red meat. Most of this risk was due to intake of red meat cooked until well/very well done and/or by high-temperature cooking techniques such as grilling. Linking the FFQ information to HCA database, the impact several HCAs on risk was evaluated. An increased risk was

  15. Holographic property of photopolymers with different amine photoinitiators

    International Nuclear Information System (INIS)

    Holographic parameters and photobleaching kinetics of the photopolymers with five different amine photoinitiators are studied. The maximum values of diffraction efficiency, photobleaching coefficient and quantum yield follow the sequence: Triethanolamine (TEA)> Diethanolamine (DEA)> Ethanolamine (EA)> Triethylamine (TETN)> Diethylamine (DETN). The holographic capabilities of photopolymer performances are determined by the number of functional groups in the amine molecular structure. There is an optimum proportion of the photoinitiator, the photosensitizer and the monomer in the test of holographic parameters with different amine concentrations. The maximum diffraction efficiency is 59.26%, sensitivity is 1.72 × 10−3 cm2/mJ, and the maximum refractive modulation index is 4.64×10−4. (classical areas of phenomenology)

  16. Synthesis, characterization and application of novel aminated gelatin hydrolysate

    International Nuclear Information System (INIS)

    Gelatin is biocompatible with body and does not harm the health, so it can be used as environmental friendly formaldehyde scavenger. The aminated gelatin with many amiqogen, carboxyl and amide functional group was synthesized by using diethylene triamine and gelatin hydrolysate, and then it was characterized using Fourier transform infrared spectrometer (FTIR) and gel penetrating chromatogram (GPC) testing. The results showed that the amidogen content increased to nearly double and the acylation reaction had occurred. Moreover, the prepared aminated gelatin was used to remove free formaldehyde in simulating air test. The application results indicated that when the dosage of aminated gelatin was 7.5g and reaction time was 20min, the percentage of formaldehyde removal reached 94 %. (author)

  17. Structural Influence on Excited State Dynamics in Simple Amines

    DEFF Research Database (Denmark)

    Klein, Liv Bærenholdt

    Simple amines are basic model system of nitrogen-containing chromophores that appear widely in nature. They are also ideal systems for detailed investigation of nonadiabatic dynamical processes and ultrafast temporal evolution of electronic states of the Rydberg type. This investigation, combining...... experiments with calculations, provides new insight into the nature of the internal conversion processes that mediate the dynamical evolution between Rydberg states, and how structural variations in simple amine system have a large impact on the non-adiabatic processes. The experimental method of choice is...... sensitive collection of photoelectron spectra. In particular, the angleresolved data available from the VMI approach provides highly detailed mechanistic insight about the relaxation pathways. One striking novel nding is that for tertiary amines, the critical factor driving the non-adiabatic dynamics is the...

  18. Synthesis and inverse emulsion polymerization of aminated acrylamidodextran.

    Science.gov (United States)

    Daubresse, C; Grandfils, C; Jérôme, R; Teyssié, P; Goethals, P; Schacht, E

    1993-12-01

    A chemically modified form of dextran was prepared, having a polymerizable moiety (acrylamide) and a reactive functional group (primary amine). Dextran was activated with 4-nitrophenyl-chloroformate (24 mol per polysaccharide, 9.8 mol per 100 glucose residues); 9.8% glucose residues were converted to aliphatic carbonates and 5.2% were converted to cyclic carbonates. The activated dextran was coupled with trityldiaminoethane (8 mol per 100 glucose residues), reactivated with 4-nitrophenylchloroformate, then coupled with acryloamidodiaminohexane (6.8 mol per 100 glucose residues). The trityl group was removed by hydrolysis with trifluoroacetic acid to yield the required aminated acryloamidodextran. The modified dextran was shown to be polymerizable by inverse emulsion polymerization. Submicron particles were successfully prepared, containing functional amine groups suitable for preparing drug conjugates or for modifying the surface properties of this biomaterial. PMID:7512648

  19. Amine-intercalated α-zirconium phosphates as lubricant additives

    International Nuclear Information System (INIS)

    In this study, three types of amines intercalated α-zirconium phosphate nanosheets with different interspaces were synthesized and examined as lubricant additives to a mineral oil. Results from tribological experiments illustrated that these additives improved lubricating performance. Results of rheological experiments showed that the viscosity of the mineral oil was effectively reduced with the addition of α-zirconium phosphate nanosheets. The two-dimensional structure, with larger interspaces, resulting from amine intercalation, exhibited improved effectiveness in reducing viscosity. This study demonstrates that the nanosheet structure of α-zirconium phosphates is effective in friction reduction. The manufacture of lubricants with tailored viscosity is possible by using different intercalators

  20. Highly Efficient N-Monomethylation of Primary Aryl Amines

    Institute of Scientific and Technical Information of China (English)

    PENG, Yiyuan; LIU, Hanliang; TANG, Min; CAI, Lisheng; PIKE, Victor

    2009-01-01

    A highly efficient method for specific synthesis of N-monomethylarylamines is presented. Anilines were treated with acetic anhydride and triethylamine in dry CH2Cl2 to give the corresponding acetamides. The subsequent N-monomethylation of acetyl aryl amines with methyl iodide and Nail in THF introduced methyl group. Acid hy- drolysis of the N-methyl acetanilides in ethylene glycol generated the corresponding N-methyl-N-aryi amines in high yields. This method was also used to synthesize (E)-2-bromo-5-(4-methylaminostyryl)pyridine that may be useful as an amyloid imaging agent for Alzheimer's disease.

  1. Studies in biogenic amine metabolism by mass spectrometry

    International Nuclear Information System (INIS)

    Two areas of mass spectral study related to biogenic amine metabolism are presented: The use of electron capture negative ion chemical ionization mass spectrometry for the quantitation of melatonin and other indole amines, and general synthetic procedures useful for the synthesis of deuterated diazomethane and deuteromethylated catechols. The factors determining instrumental sensitivity in negative ion chemical ionization are discussed, and the enhancement of the primary ion beam using magnetic fields is described. Quantitation of human plasma melatonin at the parts per trillion or pg/ml level has been demonstrated and is routinely performed as a selected ion monitoring assay. (Auth.)

  2. Influence of beer storage for the selected biogenic amines content

    OpenAIRE

    Brýdlová, Nikola

    2012-01-01

    This thesis does not only changes in the content of biogenic amines during storage of bottled beer, but beer in general. The production of beer in the world is gradually increasing. In 2010, produced a 811,4 million hectoliters of beer. Czech Republic in 2010 produced 17,1 million hectoliters in 2011 and ceased production decline. Average consumption in the Czech Republic was in 2010, 144 liters/person/year. Another chapter is devoted to biogenic amines. They are nitrogen compounds, in which ...

  3. Determination of Biogenic Amines in Different Shrimp Species for Export

    International Nuclear Information System (INIS)

    This study is part of the project on the ''Quality Assurance of Different Shrimp Species for Export''. Local shrimp samples were collected from Ministry of Livestock and Fisheries and various private enterprises. Contents of biogenic amines were determined by using benzoyl chloride derivatization method with HPLC (reverse phase high performance liquid chromatography). Based on the biogenic amines, quality index of shrimps were correlated with freshness index so that the grade of shrimp samples can be classified as excellent, good, and acceptable. All sizes of shrimps such as extra large, large, medium were found to excceptable respectively

  4. Investigation of impregnation methods in amine modification of mesoporous solids

    OpenAIRE

    Daniels, Emma; Madden, David; Curtin, Teresa

    2013-01-01

    non-peer-reviewed Carbon dioxide is one of a number of gases known as green-house gases which is thought to contribute to global climate change. CO2 released from fossil-fuel fired electric power generation plants is believed to be one of the main contributors to these emissions. A potential way to deal with these CO2 emissions is carbon dioxide capture and storage. This research investigates the application of amine-modified mesoporous silica as CO2 adsorbents. Various amine modification...

  5. Mesoporous amine-bridged polysilsesquioxane for CO2 capture

    KAUST Repository

    Qi, Genggeng

    2011-01-01

    A novel class of amine-supported sorbents based on amine-bridged mesoporous polysilsesquioxane was developed via a simple one-pot sol-gel process. The new sorbent allows the incorporation of a large amount of active groups without sacrificing surface area or pore volume available for CO2 capture, leading to a CO2 capture capacity of 3.2 mmol g−1 under simulated flue gas conditions. The sorbent is readily regenerated at 100°C and exhibits good stability over repetitive adsorption-desorption cycling.

  6. A One-Pot Approach to Pyridyl Isothiocyanates from Amines

    Directory of Open Access Journals (Sweden)

    Hao Zhang

    2014-09-01

    Full Text Available A one-pot preparation of pyridyl isothiocyanates (ITCs from their corresponding amines has been developed. This method involves aqueous iron(III chloride-mediated desulfurization of a dithiocarbamate salt that is generated in situ by treatment of an amine with carbon disulfide in the present of DABCO or sodium hydride. The choice of base is of decisive importance for the formation of the dithiocarbamate salts. This one-pot process works well for a wide range of pyridyl ITCs. Utilizing this protocol, some highly electron-deficient pyridyl and aryl ITCs are obtained in moderate to good yields.

  7. Economic Considerations for Selecting an Amine Donor in Biocatalytic Transamination

    DEFF Research Database (Denmark)

    Tufvesson, Pär; Nordblad, Mathias; Krühne, Ulrich;

    2015-01-01

    The industrial implementation of biocatalysis for production of pharma and fine chemicals has grown substantially over recent years. An upcoming application is that of chiral synthesis of optically pure amines, a technology known for many years but that is now seeing a renewed and wider interest ...... process, in particular the choice of amine donor. This paper discusses these constraints and demonstrates, through simple thermodynamic and economic models, the process targets that need to be set and achieved for a process dependent on allowed process costs and quality targets....

  8. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Science.gov (United States)

    2010-07-01

    ... sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt (generic). 721.2577 Section 721.2577... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  9. Influence of the immobilized yeast cells technology on the presence of biogenic amines in wine

    OpenAIRE

    Miličević, Borislav; Šubarić, Drago; Babić, Jurislav; Ačkar, Đurđica; Jozinović, Antun; Petošić, Emil; Matijević, Anita

    2014-01-01

    Biogenic amines are basic nitrogenous low molecular weight compounds with biological activity. Biogenic amines are important because they contain a health risk for sensitive humans. Biogenic amines in the wine can be formed from their precursors by various microorganisms present in the wine, at any stage of production. The aim of the present work was to study the changes of the content of biogenic amines in wines made from grape variety Frankovka and Pinot noir (Vitis vinifera L.) from Kutjev...

  10. The Potential of the Yeast Debaryomyces hansenii H525 to Degrade Biogenic Amines in Food

    OpenAIRE

    Mathias Bäumlisberger; Urs Moellecken; Helmut König; Harald Claus

    2015-01-01

    Twenty-six yeasts from different genera were investigated for their ability to metabolize biogenic amines. About half of the yeast strains produced one or more different biogenic amines, but some strains of Debaryomyces hansenii and Yarrowia lipolytica were also able to degrade such compounds. The most effective strain D. hanseniii H525 metabolized a broad spectrum of biogenic amines by growing and resting cells. Degradation of biogenic amines by this yeast isolate could be attributed to a pe...

  11. A protocol for amide bond formation with electron deficient amines and sterically hindered substrates

    DEFF Research Database (Denmark)

    Due-Hansen, Maria E; Pandey, Sunil K; Christiansen, Elisabeth; Andersen, Rikke; Hansen, Steffen V F; Ulven, Trond

    2016-01-01

    A protocol for amide coupling by in situ formation of acyl fluorides and reaction with amines at elevated temperature has been developed and found to be efficient for coupling of sterically hindered substrates and electron deficient amines where standard methods failed.......A protocol for amide coupling by in situ formation of acyl fluorides and reaction with amines at elevated temperature has been developed and found to be efficient for coupling of sterically hindered substrates and electron deficient amines where standard methods failed....

  12. THE UPTAKE OF CATECHOL AMINES AT HIGH PERFUSION CONCENTRATIONS IN THE RAT ISOLATED HEART: A NOVEL CATECHOL AMINE UPTAKE PROCESS

    OpenAIRE

    Iversen, LL

    1997-01-01

    In previous studies of the uptake of catechol amines in the rat isolated heart it was shown that adrenaline and noradrenaline were accumulated by a common mechanism (Iversen, 1963, 1965). In these experiments the uptake saturated at an external amine concentration of approximately 0.2 μg/ml. noradrenaline or 0.5 μg/ml. adrenaline. However, in subsequent experiments in which hearts were perfused with (±)-adrenaline at a concentration of 5.0 μg/ml. an unexpectedly large uptake of adrenaline was...

  13. 40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amine terminated bisphenol A... Significant New Uses for Specific Chemical Substances § 721.10017 Amine terminated bisphenol A diglycidyl... chemical substances identified generically as amine terminated bisphenol A diglycidyl ether polymer (PMNs...

  14. A ratiometric fluorescent probe for detection of biogenic primary amines with nanomolar sensitivity.

    Science.gov (United States)

    Mallick, Suman; Chandra, Falguni; Koner, Apurba L

    2016-02-01

    An ultrasensitive ratiometric fluorescent sensor made of an N,N-dimethylaminonaphthalene anhydride moiety for detection of aliphatic primary amines is reported. Biogenic amines at nanomolar concentration is detected with the additional ability to discriminate between primary, secondary and tertiary amines by using both UV-Visible and fluorescence spectroscopy. PMID:26734688

  15. Synthesis of sulfonamides via copper-catalyzed oxidative C-N bond cleavage of tertiary amines.

    Science.gov (United States)

    Ji, Jing; Liu, Zhengyi; Liu, Ping; Sun, Peipei

    2016-08-01

    A copper-catalyzed coupling reaction of sulfonyl chlorides with tertiary amines via the oxidative C-N bond cleavage of tertiary amines was developed. Sulfonamides were synthesized using this strategy in moderate to good yields. The reaction was applicable to various tertiary amines, as well as sulfonyl chlorides. PMID:27356858

  16. Enzymatic Sensor of Biogenic Amines with Optical Oxygen Transducer

    Czech Academy of Sciences Publication Activity Database

    Maixnerová, Lucie; Horvitz, Alexandar; Kuncová, Gabriela; Přibyl, M.; Šebela, M.; Koštejn, Martin

    Brno: Masarykova Universita, 2014, s. 173. ISBN 978-80-210-7159-9. [CEITEC Annual Conference. Brno (CZ), 21.10.2014-24.10.2014] R&D Projects: GA TA ČR TA03010544 Institutional support: RVO:67985858 Keywords : optical enzymatic biosensor * biogenic amines * mathematical model Subject RIV: CB - Analytical Chemistry, Separation

  17. Isomerization of metastable amine radical cations by dissociation-recombination

    DEFF Research Database (Denmark)

    Pedersen, Anders Holmen; Nielsen, Christian Benedikt; Bojesen, Gustav;

    2015-01-01

    The metastable molecular ions of primary aliphatic amines branched at C2 can isomerize by cleavage-recombination, thereby facilitating fragmentation reactions that require less energy than simple cleavage of the initial molecular ion. This process complements the reactions described by Audier to...

  18. AROMATIC AMINES IN AND NEAR THE BUFFALO RIVER

    Science.gov (United States)

    Three sediment samples taken from the Buffalo River and two soil samples taken near its bank have been analyzed for 2-propanol-extractable, basic organic compounds by using GC/MS. Eleven aromatic amines related to the commercial production of malachite green and crystal violet we...

  19. Advances in Biochemical Screening for Phaeochromocytoma using Biogenic Amines

    OpenAIRE

    Whiting, Malcolm J; Doogue, Matthew P

    2009-01-01

    Biochemical testing for phaeochromocytoma is performed in diagnostic laboratories using a variety of tests with plasma, serum or 24-hour urine collections. These tests include catecholamines and their methylated metabolites - the metanephrines, either individually or in combination with their sulfated metabolites. High-performance liquid chromatography (HPLC) continues to be the dominant analytical method for biogenic amine quantitation. Chromatographic techniques are changing, with improveme...

  20. Enzymatic network for production of ether amines from alcohols

    DEFF Research Database (Denmark)

    Palacio, Cyntia M.; Crismaru, Ciprian G.; Bartsch, Sebastian;

    2016-01-01

    We constructed an enzymatic network composed of three different enzymes for the synthesis of valuable ether amines. The enzymatic reactions are interconnected to catalyze the oxidation and subsequent transamination of the substrate and to provide cofactor recycling. This allows production of the ...

  1. Cloud condensation nuclei activity of aliphatic amine secondary aerosol

    Science.gov (United States)

    Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical). The resulting particle composition can contain both secondary organic aerosol (SOA) and inorganic salts. The fraction of organic to inorganic materials in the particulate ...

  2. Electrochemical degradation of aromatic amines on BDD electrodes

    International Nuclear Information System (INIS)

    The electrochemical oxidation of four aromatic amines, with different substituent groups, 3-amino-4-hydroxy-5-nitrobenzenesulfonic acid (A1), 5-amino-2-methoxybenzenesulfonic acid (A2), 2,4-dihydroxyaniline hydrochloride (A3) and benzene-1,4-diamine (A4), was performed using as anode a boron-doped diamond electrode, commercially available at Adamant Technologies. Tests were run at room temperature with model solutions of the different amines, with concentrations of 200 ppm, using as electrolyte 0.035 M Na2SO4 aqueous solutions, in a batch cell with recirculation, at different current densities (200 and 300 A m-2). The following analyses were performed with the samples collected during the assays: UV-Vis spectrophotometry, chemical oxygen demand (COD), total organic carbon (TOC), total Kjeldahl nitrogen, ammonia nitrogen, nitrates and HPLC. Results have shown a good electrodegradation of all the amines tested, with COD removals, after 6 h assays, higher than 90% and TOC removals between 60 and 80%. Combustion efficiency (ηC), which measures the tendency to convert organic carbon to CO2, was also determined for all the amines, being ηCA1 CA2 CA3 CA4 = 0.99.

  3. Gas-phase reactions of cyclopropenylidene with protonated alkyl amines.

    Science.gov (United States)

    Lin, Ziqing; Tan, Lei; Yang, Yang; Dai, Mingji; Tureček, František; Ouyang, Zheng; Xia, Yu

    2016-04-21

    Vinylidene carbenes (C3H2) are of high interest to interstellar, combustion, and organic chemistry. Due to their high instability, the direct experimental investigation of their chemical reactivity has rarely been achieved. Herein, we report a first study on the reactions of cyclopropenylidene (c-C3H2) with protonated alkyl amines in the gas phase using a home-built ion trap mass spectrometer. The high gas-phase basicity (GB) of ((1)A1) c-C3H2 (calculated as 920 kJ mol(-1)) facilitates the formation of a proton-bound dimer with protonated amines as the first step in the reaction. The dimer can stay as it is or rearrange to a covalent product. The formation of the covalent complex is highly exothermic and its yield is affected by the GB of alkyl amines. The highest yield (82%) was achieved when the GB of the amine was slightly lower but comparable to that of c-C3H2. Our results demonstrate a new reaction pathway of c-C3H2, which has long been considered as a "dead end" in interstellar carbon chemistry. PMID:26978226

  4. Effects of amine fluoride on biofilm growth and salivary pellicles

    NARCIS (Netherlands)

    Van der Mei, HC; Engels, E; de Vries, Jacob; Busscher, HJ

    2008-01-01

    The amine fluoride (AmF) N'-octadecyltrimethylendiamine-N, N,N'-tris(2-ethanol)-dihydrofluoride is a cationic antimicrobial which can have beneficial effects on plaque formation. Here, we determine changes in pellicle and bacterial cell surface properties of the strains Actinomyces naeslundii HM1, S

  5. Geographical and diurnal features of amine-enhanced boundary layer nucleation

    Science.gov (United States)

    Bergman, T.; Laaksonen, A.; Korhonen, H.; Malila, J.; Dunne, E. M.; Mielonen, T.; Lehtinen, K. E. J.; Kühn, T.; Arola, A.; Kokkola, H.

    2015-09-01

    Amines have recently been found to be an important ingredient in the nucleation and initial growth of atmospheric aerosols; however, global estimates of the spatial and temporal extent of amine-enhanced nucleation are currently missing. We utilize two recently published laboratory data sets of amine-sulfuric acid nucleation to evaluate the accuracy of previously published nucleation parameterizations and to produce a new amine-enhanced new particle formation (NPF) parameterization that better reproduces the laboratory observations at atmospherically relevant sulfuric acid concentrations. We implement and compare the amine-enhanced NPF parameterizations and a kinetic nucleation parameterization within the global aerosol-climate model ECHAM-HAMMOZ and find that the spatial features of amine-enhanced and kinetic NPF are clearly different. Amine-enhanced NPF is limited to areas near the source regions of amine due to its short gas phase residence time of 6.9 h, whereas kinetic nucleation (which depends only on sulfuric acid concentration) produces particles more uniformly across the globe due to long-range transport of SO2. The notably stronger land-sea contrast in amine-enhanced nucleation simulations is in line with relatively rare atmospheric observations of NPF over open oceans. However, when the uptake of gas phase amine molecules to aerosol particles is limited according to previously published estimates (0.2% of collisions leading to uptake), the amine-enhanced NPF parameterization predicts in some regions unrealistically high NPF rates (˜1000 cm-3 s-1) compared to typical observations. Our results indicate that amine-enhanced nucleation may be an important particle formation mechanism near amine source regions but also highlights the need for more tightly defined constraints on the spatial and temporal distribution of amine emissions, gas-to-particle partitioning mechanisms of amines, and condensation and coagulation sinks in global models.

  6. Atmospheric amines and ammonia measured with a Chemical Ionization Mass Spectrometer (CIMS

    Directory of Open Access Journals (Sweden)

    Y. You

    2014-06-01

    Full Text Available We report ambient measurements of amines and ammonia with a~fast response chemical ionization mass spectrometer (CIMS in a southeastern US forest in Alabama and a~moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv and ammonia (up to 2 ppbv were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1–C6 at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast US. At the moderately polluted Kent site, higher concentrations of amines (C1–C6, from pptv to tens of pptv and ammonia (up to 6 ppbv were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

  7. Atmospheric Amines and Ammonia Measured with a Chemical Ionization Mass Spectrometer (CIMS)

    Energy Technology Data Exchange (ETDEWEB)

    You, Y.; Kanawade, V. P.; de Gouw, J. A.; Guenther, Alex B.; Madronich, Sasha; Sierra-Hernandez, M. R.; Lawler, M.; Smith, James N.; Takahama, S.; Ruggeri, G.; Koss, A.; Olson, K.; Baumann, K.; Weber, R. J.; Nenes, A.; Guo, H.; Edgerton, Eric S.; Porcelli, L.; Brune, W. H.; Goldstein, Allen H.; Lee, S.-H

    2014-11-19

    We report ambient measurements of amines and ammonia with a fast response chemical ionization mass spectrometer (CIMS) in a Southeastern U.S. forest in Alabama and a moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv) and ammonia (up to 2 ppbv) were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1-C6) at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast U.S. At the moderately polluted Kent site, higher concentrations of amines (C1-C6, from pptv to tens of pptv) and ammonia (up to 6 ppbv) were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

  8. Synthesis, characterization, and surface wettability properties of amine functionalized graphene oxide films with varying amine chain lengths.

    Science.gov (United States)

    Shanmugharaj, A M; Yoon, J H; Yang, W J; Ryu, Sung Hun

    2013-07-01

    Surface functionalization of graphene oxide (GO) an important graphene precursor using alkylamines of varying chain lengths followed by thermal treatment resulted in the formation of superhydrophobic surfaces. Alkylamines consisting of hydrophobic long chain alkyl groups and hydrophilic amine groups were chemically reacted to the GO surface via two types of reactions viz. (i) amidation reaction between amine groups and carboxylic acid sites of GO and (ii) nucleophilic substitution reactions between amine and epoxy groups on GO surface. Successful grafting of alkylamines was confirmed using Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance ((1)H NMR), and thermogravimetric analysis (TGA). Alkylamine-modified GO surfaces showed enhanced roughness, and this effect was more pronounced with increasing amine chain length. Water contact angle measurements revealed that the hydrophobic nature of graphene depended on the chain length of the grafted alkylamines, and this fact may be corroborated to the decrease in the surface energy values. Our results indicate that superhydrophobic graphene films can be produced by thermal treatment of hexadecylamine- and octadecylamine-grafted GO films. These results will provide valuable guidance for the design and manufacture of graphene-based biomaterials, medical instruments, structural composites, electronics, and renewable energy devices. PMID:23622684

  9. INFLUENCE OF MOLECULAR STRUCTURES OF SECONDARY AMINE TERMINATED POLY(ESTER-AMINE)S ON THE CURING PERFORMANCE WITH EPOXY RESIN

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Five secondary amine terminated poly(ester-amine)s (defined as PEA) with controlled molecular structures were synthesized through reacting excessive piperazine with phthalicdiglycol diacrylate (PDDA) and 1,1,1-trimethylolpropane triacrylate (TMPTA) at a constant secondary amine/acrylate group ratio of 1.5/1 and at different PDDA/TMPTA molar ratios.Both IR and 1H-NMR spectra indicated that all acrylate groups were consumed in the reaction, based on which the structural parameters were calculated from the 1H-NMR spectra. With decreasing PDDA/TMPTA ratio, the content of secondary amine, degree of branching, molecular weight, Tg and Td increased accordingly. These polymers were further used as both crosslinkers and flexibilizers for a linear epoxy resin E51 to form cured films under ambient condition, The gel content,relative hardness and Tg of the resulting films increased as PEA molecules changed from linear to highly branching structures. Due to the flexibility of PEA molecules, all the films possessed excellent mechanical performance.

  10. Blue Chitin columns for the extraction of heterocyclic amines from urine samples

    DEFF Research Database (Denmark)

    Bang, J.; Frandsen, Henrik Lauritz; Skog, K.

    During normal cooking of meat, a class of mutagenic/carcinogenic compounds called heterocyclic amines is formed. Heterocyclic amines are rapidly absorbed and metabolised in the human body, and for estimation of the intake of heterocyclic amines, it is useful to determinate their levels in the urine....... Blue Chitin columns were used for the extraction and purification of heterocyclic amines from urine samples spiked with 14 different heterocyclic amines. The samples were analysed using LC-MS. The results show that Blue Chitin columns provide a straightforward and rapid means of extracting heterocyclic...

  11. The effect of fluorine substitution in alcohol-amine complexes

    DEFF Research Database (Denmark)

    Hansen, Anne Schou; Du, Lin; Kjærgaard, Henrik Grum

    2014-01-01

    were elucidated by Natural Bond Orbital, Atoms in Molecules and Non-covalent Interactions analysis. We find that the alcohol-amine complexes with TFE as the hydrogen bond donor form stronger hydrogen bonds and that secondary interactions between the monomers increase from MeOH to EtOH to TFE. TFE is a......The effect of fluorine substitution on the hydrogen bond strength in alcohol-amine molecular complexes was investigated, with a combination of vapour phase infrared spectroscopy and theoretical calculations. The complexes were combined from methanol (MeOH), ethanol (EtOH) and trifluoroethanol (TFE......) as the hydrogen bond donor, and either dimethylamine (DMA) or trimethylamine (TMA) as the acceptor. The fundamental OH-stretching vibration involved in hydrogen bonding was measured for all complexes, as well as the weak second NH-stretching overtone for the DMA complexes. Equilibrium constants for...

  12. Debromination of endo-(+)-3-bromocamphor with primary amines

    International Nuclear Information System (INIS)

    Reductive debromination of endo-(+)-3-bromocamphor with different primary amines followed by imine formation was investigated. This reaction requires simple experimental procedure without any organic solvent, metal or conventional reducing agent. A strong influence of amine polarity on the efficacy of debromination process was observed, and ethanolamine and ethylene diamine having sufficiently high boiling points can debrominate 3-bromocamphor giving corresponding camphanimines in good isolated yields. The mechanisms of debromination of 3-bromocamphor with ethanolamine and n-hexylamine were investigated at the B3LYP/6-311+G(d,p) level of theory. The radical mechanism was revealed, and it was shown that the reaction with more polar ethanolamine is energetically more favorable. (author)

  13. Debromination of endo-(+)-3-bromocamphor with primary amines

    Energy Technology Data Exchange (ETDEWEB)

    Markovic, Svetlana; Markovic, Violeta; Joksovic, Milan D.; Joksovic, Ljubinka, E-mail: ljubinka@kg.ac.rs [Department of Chemistry, Faculty of Science, University of Kragujevac (Serbia); Todorovic, Nina [Institute for Chemistry, Technology and Metallurgy, Belgrade (Serbia); Divjakovic, Vladimir [Department of Physics, University of Novi Sad (Serbia); Trifunovic, Snezana [Faculty of Chemistry, University of Belgrade, Belgrade, (Serbia)

    2013-07-15

    Reductive debromination of endo-(+)-3-bromocamphor with different primary amines followed by imine formation was investigated. This reaction requires simple experimental procedure without any organic solvent, metal or conventional reducing agent. A strong influence of amine polarity on the efficacy of debromination process was observed, and ethanolamine and ethylene diamine having sufficiently high boiling points can debrominate 3-bromocamphor giving corresponding camphanimines in good isolated yields. The mechanisms of debromination of 3-bromocamphor with ethanolamine and n-hexylamine were investigated at the B3LYP/6-311+G(d,p) level of theory. The radical mechanism was revealed, and it was shown that the reaction with more polar ethanolamine is energetically more favorable. (author)

  14. Extraction of beryllium sulfate by a long chain amine

    International Nuclear Information System (INIS)

    The extraction of sulfuric acid in aqueous solution by a primary amine in benzene solution, 3-9 (diethyl) - 6-amino tri-decane (D.E.T. ) - i.e., with American nomenclature 1-3 (ethyl-pentyl) - 4-ethyl-octyl amine (E.P.O.) - has made it possible to calculate the formation constants of alkyl-ammonium sulfate and acid sulfate. The formula of the beryllium and alkyl-ammonium sulfate complex formed in benzene has next been determined, for various initial acidity of the aqueous solution. Lastly, evidence has been given of negatively charged complexes of beryllium and sulfate in aqueous solution, through the dependence of the aqueous sulfate ions concentration upon beryllium extraction. The formation constant of these anionic complexes has been evaluated. (author)

  15. Amides derived from heteroaromatic amines and selected steryl hemiesters

    Czech Academy of Sciences Publication Activity Database

    Bildziukevich, Uladzimir; Rárová, L.; Šaman, David; Havlíček, Libor; Drašar, P.; Wimmer, Zdeněk

    2013-01-01

    Roč. 78, č. 14 (2013), s. 1347-1352. ISSN 0039-128X R&D Projects: GA ČR(CZ) GAP503/11/0616 Grant ostatní: GA MŠk(CZ) ED0007/01/01 Institutional support: RVO:61389030 ; RVO:61388963 Keywords : Heteroaromatic amine * Cholesterol * Lanosterol Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.716, year: 2013

  16. DNA Release Dynamics from Bioreducible Poly(amido amine) Polyplexes

    OpenAIRE

    Wan, Lei; You, Yezi; Zou, Yi; Oupický, David; Mao, Guangzhao

    2009-01-01

    The molecular disassembly and DNA release dynamics of bioreducible poly(amido amine) polyplexes were studied in real time by atomic force microscopy (AFM). Molecular disassembly of polyplexes constitutes a critical step along the nonviral gene delivery pathway. DNA release is triggered by the depolymerization of high-molecular-weight polycations into low-molecular-weight oligocations utilizing the thiol and disulfide exchange reaction mechanism. The research is motivated by low cytotoxicity a...

  17. Electrophysiological effects of trace amines on mesencephalic dopaminergic neurons

    Directory of Open Access Journals (Sweden)

    Ada eLedonne

    2011-07-01

    Full Text Available Trace amines (TAs are a class of endogenous compounds strictly related to classic monoamine neurotransmitters with regard to their structure, metabolism and tissue distribution. Although the presence of TAs in mammalian brain has been recognized for decades, until recently they were considered to be by-products of amino acid metabolism or as ‘false’ neurotransmitters. The discovery in 2001 of a new family of G protein-coupled receptors (GPCRs, namely trace amines receptors, has re-ignited interest in TAs. In particular, two members of the family, trace amine receptor 1 (TA1 and trace amine receptor 2 (TA2, were shown to be highly sensitive to these endogenous compounds. Experimental evidence suggests that TAs modulate the activity of catecholaminergic neurons and that TA dysregulation may contribute to neuropsychiatric disorders, including schizophrenia, attention deficit hyperactivity disorder, depression and Parkinson’s disease, all of which are characterised by altered monoaminergic networks. Here we review recent data concerning the electrophysiological effects of TAs on the activity of mesencephalic dopaminergic neurons. In the context of recent data obtained with TA1 receptor knockout mice, we also discuss the mechanisms by which the activation of these receptors modulates the activity of these neurons. Three important new aspects of TAs action have recently emerged: (a inhibition of firing due to increased release of dopamine; (b reduction of D2 and GABAB receptor-mediated inhibitory responses (excitatory effects due to dysinhibition; and (c a direct TA1 receptor-mediated activation of GIRK channels which produce cell membrane hyperpolarization. While the first two effects have been well documented in our laboratory, the direct activation of GIRK channels by TA1 receptors has been reported by others, but has not been seen in our laboratory (Geracitano et al., 2004. Further research is needed to address this point, and to further

  18. Diluent Effects in Amine Extraction of Sulfuric Acid

    Czech Academy of Sciences Publication Activity Database

    Procházka, Jaroslav; Heyberger, Aleš; Volaufová, Eva

    Praha : Process Engineering Publisher, 2004, s. 561. ISBN 80-86059-40-5. [International Congress of Chemical and Process Engineering CHISA 2004 /16./. Praha (CZ), 22.08.2004-26.08.2004] R&D Projects: GA ČR GA104/02/1108 Institutional research plan: CEZ:AV0Z4072921 Keywords : diluent effects * amine extraction * sulfurid acid Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  19. Biogenic amines in smear and mould-ripened cheeses

    OpenAIRE

    Pavel Pleva; Leona Buňková; Eva Theimrová; Vendula Bartošáková; František Buňka; Khatantuul Purevdorj

    2014-01-01

    The aim of the study was the monitoring of six biogenic amines (histamine, tyramine, phenylethylamine, tryptamine, putrescine, and cadaverine) and two polyamines (spermidine and spermine) in 30 samples of dairy products purchased in the Czech Republic, namely in 15 samples of mould-ripened cheeses and in 15 samples of smear-ripened cheeses. A further goal was the microbiological analysis of the individual samples of cheeses (total count of microorganisms, number of enterobacteria, enterococci...

  20. Analysis of Some Biogenic Amines by Micellar Liquid Chromatography

    OpenAIRE

    Irena Malinowska; Katarzyna E. Stępnik

    2012-01-01

    Micellar liquid chromatography (MLC) with the use of high performance liquid chromatography (HPLC) was used to determine some physicochemical parameters of six biogenic amines: adrenaline, dopamine, octopamine, histamine, 2-phenylethylamine, and tyramine. In this paper, an influence of surfactant’s concentration and pH of the micellar mobile phase on the retention of the tested substances was examined. To determine the influence of surfactant’s concentration on the retention of the tested ami...

  1. Ionic-Liquid-Supported Synthesis of Amines and Derivatives

    OpenAIRE

    Debdab, Mansour; Mongin, Florence; Bazureau, J.P.

    2006-01-01

    International audience Amine precursors such as glycines protected at nitrogen with a Boc or formyl group were grafted by esterification on the hydroxylated arms of 1-(2-hydroxyethyl)-3-methylimidazolium hexafluorophosphates or tetrafluoroborates. The cleavage of the Boc group was then realized at room temperature by successively treating acetonitrile solutions of the thus formed glycinates with methanol and acetyl chloride (two equivalents each). Interestingly, the resulting glycinate hyd...

  2. Bioactive amines and internal quality of commercial eggs.

    Science.gov (United States)

    Figueiredo, T C; Viegas, R P; Lara, L J C; Baião, N C; Souza, M R; Heneine, L G D; Cançado, S V

    2013-05-01

    The physicochemical and microbiological qualities of commercial eggs produced by layer hens of different ages (approximately 30 and 60 wk old) were submitted to storage under room temperature or refrigeration for 28 d. A total of 600 eggs were subjected to microbiological analyses of their inner contents and another 600 to a determination of Haugh units (HU) and bioactive amine content. A decrease in the quality of the inner contents of the eggs was observed during the experiment, mainly in the eggs from the 60-wk-old layers, which presented the worst HU values when stored at room temperature (P Pseudomonas spp., mesophilic aerobic bacteria, and fungi were also recorded. The chromatographic analysis of bioactive amines detected the presence of phenylethylamine in all albumens (38.0 mg/kg) and spermidine in the yolks (1.02 mg/kg). It was concluded that the age of the hens and the time and temperature of storage influenced the quality parameters of the eggs (P < 0.05). Furthermore, despite the low levels of microbial contamination found, phenylethylamine was detected in the albumen. It was not possible to establish index of quality of eggs using bioactive amines present in the yolk and albumen of eggs. PMID:23571349

  3. Boron carbide nitride derived from amine-boranes

    International Nuclear Information System (INIS)

    This paper reports that amine-boranes such as pyridine- or piperazine-borane can be converted into infusible polymers by thermal crosslinking at temperatures up to 420 degrees C. Further rise of the temperature up to 1050 degrees C in argon results in transformation of the polymers into black residues. Microstructural (TEM/EELS, ESCA) and chemical investigations indicate the presence of single phase boron carbide nitrides which exhibit a graphite-like, turbostratic structure with a homogeneous distribution of the elements B, N, and C. Subsequent annealing at 2200 degrees C in argon gives rise to crystallization of the pyrolytic material generating the thermodynamically stable phases BN, C, and B4C. The semiconducting properties of the X-ray amorphous boron carbide nitride synthesized at 1050 degrees C depend on the B/N/C-ratio which can be influenced by the type of amine-borane-precursor and by the applied atmosphere (Ar or NH3) during pyrolysis. The amine-boranes can be converted into boron carbide nitride- and BN-monoliths at 1050 degrees C under argon or reactive gas (NH3), respectively. The monoliths are transformed into composites with 91% rel. density containing BN, C, and B4C when heated up to 2200 degrees C

  4. Amine-functionalized polypyrrole: Inherently cell adhesive conducting polymer.

    Science.gov (United States)

    Lee, Jae Y; Schmidt, Christine E

    2015-06-01

    Electrically conducting polymers (CPs) have been recognized as novel biomaterials that can electrically communicate with biological systems. For their tissue engineering applications, CPs have been modified to promote cell adhesion for improved interactions between biomaterials and cells/tissues. Conventional approaches to improve cell adhesion involve the surface modification of CPs with biomolecules, such as physical adsorption of cell adhesive proteins and polycationic polymers, or their chemical immobilization; however, these approaches require additional multiple modification steps with expensive biomolecules. In this study, as a simple and effective alternative to such additional biomolecule treatment, we synthesized amine-functionalized polypyrrole (APPy) that inherently presents cell adhesion-supporting positive charges under physiological conditions. The synthesized APPy provides electrical activity in a moderate range and a hydrophilic surface compared to regular polypyrrole (PPy) homopolymers. Under both serum and serum-free conditions, APPy exhibited superior attachment of human dermal fibroblasts and Schwann cells compared to PPy homopolymer controls. Moreover, Schwann cell adhesion onto the APPy copolymer was at least similar to that on poly-l-lysine treated PPy controls. Our results indicate that amine-functionalized CP substrates will be useful to achieve good cell adhesion and potentially electrically stimulate various cells. In addition, amine functionality present on CPs can further serve as a novel and flexible platform to chemically tether various bioactive molecules, such as growth factors, antibodies, and chemical drugs. PMID:25294089

  5. DFT investigation on dihydrogen-bonded amine-borane complexes.

    Science.gov (United States)

    Yan, Shihai; Zou, Hongmei; Kang, Wukui; Sun, Lixiang

    2016-01-01

    The DFT method has been employed in the exploration on dihydrogen-bonded amine-borane complexes, with a special emphasis on the dimerization and substituent group effect. Stable dihydrogen bonded complexes can be generated from these amine-borane monomers with the appearance of NH(δ+)…H(δ-)B interactions. The binding energy decreases gradually with the increase of the steric effect of the substituents. The substituent group number mainly varies the C-N bond length. The dimerization generates close H…H and influences predominantly the N-B distance. The effect of dimerization on IR and vibrational circular dichroism (VCD) spectra is stronger than that of the number of substituent groups, which leads to distinct NBO charge variation on α-C. Both the substituent group number and dimerization enhance the chemical shift difference between hydrogen atoms covalently bonded to N and B, Δδ H-H, which can be hired as an index for structural determination. It is proposed that amine-borane complexes with more substituent groups in higher degree of polymerization are potentially interesting materials for hydrogen storage. Graphical Abstract Both the number of substituent group and dimerization enhance the chemical shift difference of hydrogen atoms covalently bonded on N and B, Δδ H-H, which can be employed as an index for the structural determination. PMID:26696542

  6. A Review: Microbiological, Physicochemical and Health Impact of High Level of Biogenic Amines in Fish Sauce

    Directory of Open Access Journals (Sweden)

    Muhammad Z. Zaman

    2009-01-01

    Full Text Available Problem statement: Biogenic amines are basic nitrogenous compounds present in a wide variety of foods and beverages. Their formations were mainly due to the amino acids decarboxylase activity of certain microorganisms. Excessive intake of biogenic amines could induce many undesirable physiological effects determined by their psychoactive and vasoactive action. Fish sauce which is considered as a good source of dietary protein, amino acids, vitamins and minerals was a popular condiment in Southeast Asian countries. However, it has also been reported that fish sauce contain high amount of amines. Hence, attention should be given to ensure the safety of this product. Approach: A review study was conducted to deliver an overview on the presence of biogenic amines in fish sauce and to discuss the important factors affecting their accumulation. Impact of amines on human health and efforts to reduce their accumulation in fish sauce were also discussed to give a comprehensive view. Results: Histamine, putrescine and cadaverine is the most abundant amines in fish sauce with maximum reported value of 1220, 1257 and 1429 ppm, respectively. Tyramine present in a lesser amount with maximum reported value of 1178 ppm. Other amines such as tryptamine, phenylethylamine, spermine and spermidine were considered as minor amines. However, different profiles of amines were reported in different type of products. This was depended on microbial flora, availability of precursors and physicochemical factors such as temperature, pH, salt, oxygen and sugar concentration. In synergistically supporting physicochemical factors, several microorganisms such as Enterobacteriaceae, Micrococci and Lactobacilli were responsible for biogenic amines formation in fish sauce. Conclusion: Since the formation of amines in fish sauce was a result of many factors, it was almost virtually impossible to control each factor during fermentation. Addition of amines degrading bacteria into fish

  7. Equilibrium and Transport Properties of Primary, Secondary and Tertiary Amines by Molecular Simulation

    Directory of Open Access Journals (Sweden)

    Orozco Gustavo A.

    2014-09-01

    Full Text Available Using molecular simulation techniques such as Monte Carlo (MC and molecular dynamics (MD, we present several simulation results of thermodynamic and transport properties for primary, secondary and tertiary amines. These calculations are based on a recently proposed force field for amines that follows the Anisotropic United Atom approach (AUA. Different amine molecules have been studied, including n-ButylAmine, di-n-ButylAmine, tri-n-ButylAmine and 1,4-ButaneDiAmine for primary, secondary, tertiary and multi-functional amines respectively. For the transport properties, we have calculated the viscosity coefficients as a function of temperature using the isothermal-isobaric (NPT ensemble. In the case of the pure components, we have investigated different thermodynamic properties using NVT Gibbs ensemble simulations such as liquid-vapor phase equilibrium diagrams, vaporization enthalpies, vapor pressures, normal boiling points, critical temperatures and critical densities. We have also calculated the excess enthalpies for water-n-ButylAmine and n-heptane-n-ButylAmine mixtures using Monte Carlo simulations in the NPT ensemble. In addition, we present the calculation of liquid-vapor surface tensions of n-ButylAmine using a two-phase NVT simulation as well as the radial distribution functions. Finally, we have investigated the physical Henry constants of nitrous oxide (N2O and nitrogen (N2 in an aqueous solutions of n-ButylAmine. In general, we found a good agreement between the available experimental information and our simulation results for all the studied properties, ratifying the predictive capability of the AUA force field for amines.

  8. Commercially Supplied Amine-Modified siRNAs May Require Ultrafiltration prior to Conjugation with Amine-Reactive Compounds

    OpenAIRE

    Shannen Lau; White, Paul J.; Pouton, Colin W.; Boyd, Ben J.; Bim Graham

    2011-01-01

    Conjugation of siRNA to macromolecules such as serum albumin has multiple potential benefits, including enhanced extravasation via albumin-mediated transcytosis across endothelial cells and reduced renal clearance. In attempting to conjugate siRNA to albumin, we used commercially sourced amine-modified siRNA and reacted it with the heterobifunctional linker succinimidyl 4-[N-maleimidomethyl]cyclohexane-1-carboxylate (SMCC) to introduce a maleimide group suitable for conjugation to the thiol g...

  9. Temperature-Dependent Henry's Law Constants of Atmospheric Amines.

    Science.gov (United States)

    Leng, Chunbo; Kish, J Duncan; Roberts, Jason E; Dwebi, Iman; Chon, Nara; Liu, Yong

    2015-08-20

    There has been growing interest in understanding atmospheric amines in the gas phase and their mass transfer to the aqueous phase because of their potential roles in cloud chemistry, secondary organic aerosol formation, and the fate of atmospheric organics. Temperature-dependent Henry's law constants (KH) of atmospheric amines, a key parameter in atmospheric chemical transport models to account for mass transfer, are mostly unavailable. In this work, we investigated gas-liquid equilibria of five prevalent atmospheric amines, namely 1-propylamine, di-n-propylamine, trimethylamine, allylamine, and 4-methylmorpholine using bubble column technique. We reported effective KH, intrinsic KH, and gas phase diffusion coefficients of these species over a range of temperatures relevant to the lower atmosphere for the first time. The measured KH at 298 K and enthalpy of solution for 1-propylamine, di-n-propylamine, trimethylamine, allylamine, and 4-methylmorpholine are 61.4 ± 4.9 mol L(-1) atm(-1) and -49.0 ± 4.8 kJ mol(-1); 14.5 ± 1.2 mol L(-1) atm(-1) and -72.5 ± 6.8 kJ mol(-1); 8.9 ± 0.7 mol L(-1) atm(-1) and -49.6 ± 4.7 kJ mol(-1); 103.5 ± 10.4 mol L(-1) atm(-1) and -42.7 ± 4.3 kJ mol(-1); and 952.2 ± 114.3 mol L(-1) atm(-1) and -82.7 ± 9.7 kJ mol(-1), respectively. In addition, we evaluated amines' characteristic times to achieve gas-liquid equilibrium for partitioning between gas and aqueous phases. Results show gas-liquid equilibrium can be rapidly established at natural cloud droplets surface, but the characteristic times may be extended substantially at lower temperatures and pHs. Moreover, our findings imply that atmospheric amines are more likely to exist in cloud droplets, and ambient temperature, water content, and pH of aerosols play important roles in their partitioning. PMID:26200814

  10. From caffeine to fish waste: amine compounds present in food and drugs and their interactions with primary amine oxidase.

    LENUS (Irish Health Repository)

    Olivieri, Aldo

    2011-07-01

    Tissue bound primary amine oxidase (PrAO) and its circulating plasma-soluble form are involved, through their catalytic activity, in important cellular roles, including the adhesion of lymphocytes to endothelial cells during various inflammatory conditions, the regulation of cell growth and maturation, extracellular matrix deposition and maturation and glucose transport. PrAO catalyses the oxidative deamination of several xenobiotics and has been linked to vascular toxicity, due to the generation of cytotoxic aldehydes. In this study, a series of amines and aldehydes contained in food and drugs were tested via a high-throughput assay as potential substrates or inhibitors of bovine plasma PrAO. Although none of the compounds analyzed were found to be substrates for the enzyme, a series of molecules, including caffeine, the antidiabetics phenformin and tolbutamide and the antimicrobial pentamidine, were identified as PrAO inhibitors. Although the inhibition observed was in the millimolar and micromolar range, these data show that further work will be necessary to elucidate whether the interaction of ingested biogenic or xenobiotic amines with PrAO might adversely affect its biological roles.

  11. [Analysis of amines in water samples by high performance liquid chromatography-laser induced fluorescence detection].

    Science.gov (United States)

    Liu, Fan; Gao, Fangyuan; Tang, Tao; Sun, Yuanshe; Li, Tong; Zhang, Weibing

    2013-11-01

    A sensitive high performance liquid chromatography (HPLC)-laser induced fluorescence detection (LIFD) method was developed for the determination of amines. The derivatization and separation conditions were investigated. Under the optimized conditions, spermidine, putrescine and histamine were analyzed. The limits of detection (LODs) of the three biogenic amines (S/N = 3) were as low as 10(-10) mol/L. This method showed excellent stability. The RSDs of retention times and peak areas of the three biogenic amines were lower than 0.3% and 3%, respectively. This method was applied in biogenic amine analysis in water samples, and the average recoveries were in the range of 94.99%-104.7%. Furthermore, the amines in seven tea samples were analyzed by this method, and satisfactory results were achieved. The developed assay is of excellent sensitivity and good reproducibility, which can be used in the analysis of the amines in water samples. PMID:24558849

  12. Biogenic amines in commercially produced Yulu, a Chinese fermented fish sauce.

    Science.gov (United States)

    Jiang, Wei; Xu, Ying; Li, Chunsheng; Dong, Xiaoyan; Wang, Dongfeng

    2014-01-01

    Seven biogenic amines were determined in 35 commercially produced Yulu samples from three provinces of China by pre-column derivatisation with dansyl chloride (Dns-Cl) and high-performance liquid chromatography with fluorescence detection (HPLC-FLD). Putrescine, cadaverine, histamine and tyramine were the major biogenic amines (more than 100 mg kg(-1)), while tryptamine, spermidine and spermine were regarded as minor biogenic amines (less than 25 mg kg(-1)). Twenty samples contained more than 50 mg kg(-1) histamine (the limit for histamine in seafood products as suggested by the Food and Drug Administration). Twenty-one samples contained more than 100 mg kg(-1) tyramine and 10 contained more than 1000 mg kg(-1) total biogenic amines. This study provided data on biogenic amine levels in Chinese fermented fish sauce. The results suggested that biogenic amine content should be monitored in commercially produced Yulu. PMID:24779975

  13. Decomposition of some amines and amino acids in steam generator environments

    International Nuclear Information System (INIS)

    Hydrothermal decomposition rate constants and high temperature pH values of some selected high-molecular weight amines and amino acids were measured under simulated steam generator conditions. These amines and amino acids were evaluated as potential crevice buffering agents for steam generator applications in pressurized water reactors. The study showed that, although the high molecular weight amines undergo hydrothermal decomposition, they have a better buffer capacity than their low molecular weight counterparts at 290 C. The amines provide effective crevice buffering by increasing the pH of the simulated crevice solution by as much as 2.84 to 4.24 units. However, volatility data for the amines and amino acids are needed before in-plant testing to ensure that amines can concentrate sufficiently in steam generator crevices to provide effective buffering

  14. Sponges with covalently tethered amines for high-efficiency carbon capture

    KAUST Repository

    Qi, Genggeng

    2014-12-12

    © 2014 Macmillan Publishers Limited. All rights reserved. Adsorption using solid amine sorbents is an attractive emerging technology for energy-efficient carbon capture. Current syntheses for solid amine sorbents mainly based on physical impregnation or grafting-to methods (for example, aminosilane-grafting) lead to limited sorbent performance in terms of stability and working capacity, respectively. Here we report a family of solid amine sorbents using a grafting-from synthesis approach and synthesized by cationic polymerization of oxazolines on mesoporous silica. The sorbent with high amount of covalently tethered amines shows fast adsorption rate, high amine efficiency and sorbent capacity well exceeding the highest value reported to date for lowerature carbon dioxide sorbents under simulated flue gas conditions. The demonstrated efficiency of the new amine-immobilization chemistry may open up new avenues in the development of advanced carbon dioxide sorbents, as well as other nitrogen-functionalized systems.

  15. Study on synthesis, application and mechanism of benzophenone/amine initiator

    International Nuclear Information System (INIS)

    Through Michael addition reaction of trimethylolpropane triacrylate (TMPTA) with diethylamine (DEA), a new kind of tertiary amine derivative was synthesized and its structure was identified by 'H-NMR. When used in combination with benzophenone, this amine presented excellent curing speed and could be a substitute for initiator Darocur R 1173, which is effective but expensive. If so, the cost of UV-curable coatings can descend apparently. The functioning mechanism of benzophenone/amine bimolecular initiator was studied

  16. Molecular methods for the detection of biogenic amine-producing bacteria on foods

    OpenAIRE

    Landete, José María; Rivas, Blanca de las; Marcobal, Angela; Muñoz, Rosario

    2007-01-01

    Biogenic amines are low molecular weight organic bases that can be detected in raw and processed foods. Several toxicological problems resulting from the ingestion of food containing biogenic amines have been described. Biogenic amines are mainly produced by the decarboxylation of certain amino acids by microbial action. Since the ability of microorganisms to decarboxylate amino acid is highly variable, being in most cases strain-specific, the detection of bacteria possessing amino a...

  17. Formation of biogenic amines and vitamin K contents in the Norwegian autochthonous cheese Gamalost during ripening

    OpenAIRE

    Qureshi, Tahir; Vermeer, Cees; Vegarud, Gerd; Abrahamsen, Roger; Skeie, Siv

    2013-01-01

    Gamalost, a Norwegian mould (Mucor mucedo) ripened autochthonous cheese, is a potential functional food due to a high content of peptides that might reduce hypertension, however it has a high content of free amino acids which may be precursors for biogenic amines. This study aimed to investigate if Gamalost might have further health benefits or risks by determination of the formation of vitamin K and biogenic amines. The development of biogenic amines and vitamin K was analysed during ripenin...

  18. Analysis of Biogenic Amines by GC/FID and GC/MS

    OpenAIRE

    Nakovich, Laura

    2003-01-01

    Low levels of biogenic amines occur naturally, but high levels (FDA sets 50 ppm of histamine in fish as the maximum allowable level) can lead to scombroid poisoning. Amines in general are difficult to analyze by Gas Chromatography (GC) due to their lack of volatility and their interaction with the GC column, often leading to significant tailing and poor reproducibility. Biogenic amines need to be derivatized before both GC and HPLC analyses. The objective of this research was to devel...

  19. Improved multiplex-PCR method for the simultaneous detection of food bacteria producing biogenic amines

    OpenAIRE

    Marcobal, Ángela; Rivas, Blanca de las; Muñoz, Rosario

    2006-01-01

    The presence of biogenic amines in foods is of considerable public concern for the food industry and the regulatory agencies, since given the potential health hazard, there is a growing demand from consumers and control authorities to reduce the allowable limits of biogenic amines in foods and beverages. Rapid and simple methods are needed for the analysis of the ability to form biogenic amines by bacteria in order to evaluate the potential risk of bacterial occurring in ...

  20. Biogenic amines degradation by malolactic bacteria: towards a potential application in wine

    OpenAIRE

    GiuseppeSpano; VittorioCapozzi; Alvarez, Miguel A.; DanielaFiocco; FrancescoGrieco

    2012-01-01

    Biogenic amines in wine represent a toxicological risk for the health of the consumer, with several trade implications. In this study 26 strains of Lactobacillus plantarum were analysed for their ability to degrade biogenic amines commonly found during wine fermentation. Two strains of L. plantarum were selected in reason of their ability to degrade putrescine and tyramine. The degradation was assessed in vitro, both in presence of the biogenic amines and in presence of the specific chemical ...

  1. Biogenic amines degradation by Lactobacillus plantarum: toward a potential application in wine

    OpenAIRE

    Capozzi, Vittorio; Russo, Pasquale; Ladero, Victor; Fernández, María; Fiocco, Daniela; Alvarez, Miguel A.; Grieco, Francesco; Spano, Giuseppe

    2012-01-01

    Biogenic amines in wine represent a toxicological risk for the health of the consumer, with several trade implications. In this study 26 strains of Lactobacillus plantarum were analysed for their ability to degrade biogenic amines commonly found during wine fermentation. Two strains of L. plantarum were selected in reason of their ability to degrade putrescine and tyramine. The degradation was assessed in vitro, both in presence of the biogenic amines and in presence of the specific chemical ...

  2. Control of biogenic amines in fermented sausages: role of starter cultures

    OpenAIRE

    MariluzLatorre-Moratalla; SaraBover-Cid

    2012-01-01

    Biogenic amines show biological activity and exert undesirable physiological effects when absorbed at high concentrations. Biogenic amines are mainly formed by microbial decarboxylation of amino acids and thus are usually present in a wide range of foods, fermented sausages being one of the major biogenic amine sources. The use of selected starter cultures is one of the best technological measures to control aminogenesis during meat fermentation. Although with variable effectiveness, several ...

  3. Control of Biogenic Amines in Fermented Sausages: Role of Starter Cultures

    OpenAIRE

    Latorre-Moratalla, M.L.; Bover-Cid, Sara; Veciana-Nogués, M.T.; Vidal-Carou, M.C.

    2012-01-01

    Biogenic amines show biological activity and exert undesirable physiological effects when absorbed at high concentrations. Biogenic amines are mainly formed by microbial decarboxylation of amino acids and thus are usually present in a wide range of foods, fermented sausages being one of the major biogenic amine sources. The use of selected starter cultures is one of the best technological measures to control aminogenesis during meat fermentation. Although with variable effectiveness, several ...

  4. Screening of biogenic amine production by lactic acid bacteria isolated from grape musts and wine

    OpenAIRE

    Moreno-Arribas, M. Victoria; Polo, María Carmen; Jorganes, Felisa; Muñoz, Rosario

    2003-01-01

    The potential to produce the biogenic amines tyramine, histamine and putrescine, was investigated for lactic acid bacteria (LAB) of various origin, including commercial malolactic starter cultures, type strains and 78 strains isolated from Spanish grape must and wine. The presence of biogenic amines in a decarboxylase synthetic broth was determined by reverse-phase high performance liquid chromatography (RP-HPLC). Tyramine was the main amine formed by the LAB strains investigated. ...

  5. Composition of amino acids and bioactive amines in common wines of Brazil

    OpenAIRE

    Bruna Carla Agustini; Daniel Braga de Lima; Tania Maria Bordin Bonfim

    2014-01-01

    Since most consumed wines in Brazil are common wines and since their representativeness is not accounted for in scientific research, current study quantifies bioactive amines and their precursors in Brazilian sweet and dry common wines, correlates the formation of amines with physical and chemical parameters and clusters studied areas by their amine and amino acid contents. Forty-seven wine samples varying in type, color and origin were analyzed simultaneously for seventeen amino acids, ammon...

  6. Activation of water soluble amines by halogens for trapping methyl radioactive iodine from air streams

    Science.gov (United States)

    Deitz, Victor R.; Blachly, Charles H.

    1977-01-01

    Gas adsorbent charcoals impregnated with an aqueous solution of the reaction product of a tertiary amine and elemental iodine or bromine are better than 99 per cent efficient in trapping methyl iodine.sup.131. The chemical addition of iodine or bromine to the tertiary amine molecule increases the efficiency of the impregnated charcoal as a trapping agent, and in conjunction with the high flash point of the tertiary amine raises the ignition temperature of the impregnated charcoal.

  7. Electron beam induced electronic transport in alkyl amine-intercalated VOx nanotubes

    OpenAIRE

    O'Dwyer, Colm; Lavayen, Vladimir; Clavijo-Cedeno, C.; Sotomayor Torres, Clivia M.

    2008-01-01

    The electron beam induced electronic transport in primary alkyl amine-intercalated V2O5 nanotubes is investigated where the organic amine molecules are employed as molecular conductive wires to an aminosilanized substrate surface and contacted to Au interdigitated electrode contacts. The results demonstrate that the high conductivity of the nanotubes is related to the non-resonant tunnelling through the amine molecules and a reduced polaron hopping conduction through the vanadium oxide itself...

  8. An improved reagent for determination of aliphatic amines with fluorescence and online atmospheric chemical ionization-mass spectrometry identification

    International Nuclear Information System (INIS)

    An improved reagent named 2-[2-(dibenzocarbazole)-ethoxy] ethyl chloroformate (DBCEC-Cl) for the determination of aliphatic amines by high-performance liquid chromatography (HPLC) with fluorescence detection and post-column online atmospheric chemical ionization-mass spectrometry (APCI-MS) identification has been developed. DBCEC-Cl could easily and quickly label aliphatic amines. Derivatives were stable enough to be efficiently analyzed by HPLC and showed an intense protonated molecular ion corresponding m/z [M+H]+ under APCI-MS in positive-ion mode. The ratios for fluorescence responses were IDBCEC-amine/IBCEC-amine = 1.02-1.60; IDBCEC-amine/IBCEOC-amine = 1.30-2.57; and IDBCEC-amine/IFMOC-amine = 2.20-4.12 (here, I was relative fluorescence intensity). The ratios for MS responses were ICDBCEC-amine/ICBCEC-amine = 4.16-29.31 and ICDBCEC-amine/ICBCEOC-amine = 1.23-2.47 (Here, IC: APCI-MS ion current intensity). Detection limits calculated from 0.0244 pmol injection, at a signal-to-noise ratio of 3, were 0.3-3.0 fmol. The relative standard deviations for within-day determination (n = 6) were 0.045-0.081% for retention time and 0.86-1.03% for peak area for the tested aliphatic amines. The mean intra- and inter-assay precision for all amine levels were 0.9991.

  9. Chemical and Molecular Descriptors for the Reactivity of Amines with CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Anita S.; Kitchin, John R.

    2012-10-24

    Amine-based solvents are likely to play an important role in CO{sub 2} capture applications in the future, and the identification of amines with superior performance will facilitate their use in CO{sub 2} capture. While some improvements in performance will be achieved through process modifications, modifying the CO{sub 2} capture performance of an amine also implies in part an ability to modify the reactions between the amine and CO{sub 2} through development of new functionalized amines. We present a computational study of trends in the reactions between CO{sub 2} and functionalized amines with a focus on identifying molecular descriptors that determine trends in reactivity. We examine the formation of bicarbonate and carbamate species on three classes of functionalized amines: alkylamines, alkanolamines, and fluorinated alkylamines including primary, secondary and tertiary amines in each class. These functional groups span electron-withdrawing to donating behavior, hydrogen-bonding, extent of functionalization, and proximity effects of the functional groups. Electron withdrawing groups tend to destabilize CO{sub 2} reaction products, whereas electron-donating groups tend to stabilize CO{sub 2} reaction products. Hydrogen bonding stabilizes CO{sub 2} reaction products. Electronic structure descriptors based on electronegativity were found to describe trends in the bicarbonate formation energy. A chemical correlation was observed between the carbamate formation energy and the carbamic acid formation energy. The local softness on the reacting N in the amine was found to partially explain trends carbamic acid formation energy.

  10. Mechanistic insights into the oxidative dehydrogenation of amines to nitriles in continuous flow

    DEFF Research Database (Denmark)

    Corker, Emily C.; Ruiz-Martínez, Javier; Riisager, Anders;

    2015-01-01

    The oxidative dehydrogenation of various aliphatic amines to their corresponding nitrile compounds using RuO2/Al2O3 catalysts in air was successfully applied to a continuous flow reaction. Conversions of amines (up to >99%) and yields of nitriles (up to 77%) varied depending on reaction conditions...... and the amine utilised. The presence of water was found to be important for the activity and stability of the RuO2/Al2O3 catalyst. The Hammett relationship and in situ infrared spectroscopy were applied to divulge details about the catalytic mechanism of the oxidative dehydrogenation of amines over Ru...

  11. Effect of radioprotective biogenic amines on peroxide oxidation of lipids in rat small intestine mucosa microsomes

    International Nuclear Information System (INIS)

    The radioprotective biogenic amines, dopamine, histamine, and serotonin inhibited lipid peroxidation in rat small intestine mucosal microsomes. Possible mechanisms of these inhibitory effects are discussed

  12. Amination of ω-Functionalized Aliphatic Primary Alcohols by a Biocatalytic Oxidation–Transamination Cascade

    OpenAIRE

    Pickl, Mathias; Fuchs, Michael; Glueck, Silvia. M.; Faber, Kurt

    2015-01-01

    Amination of non-activated aliphatic fatty alcohols to the corresponding primary amines was achieved through a five-enzyme cascade reaction by coupling a long-chain alcohol oxidase from Aspergillus fumigatus (LCAO_Af) with a ω-transaminase from Chromobacterium violaceum (ω-TA_Cv). The alcohol was oxidized at the expense of molecular oxygen to yield the corresponding aldehyde, which was subsequently aminated by the PLP-dependent ω-TA to yield the final primary amine product. The overall cascad...

  13. Secondary Amine Functional Disiloxanes as CO2 Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, MJ; Farnum, RL; Perry, RJ; Genovese, SE

    2014-05-01

    A series of two different types of secondary amine functional disiloxanes were prepared and screened as CO2 capture solvents. The first group of materials contained RNHCH2CH2CH2 side chains where the R groups were C1-6 alkyls. When R was a primary alkyl group, these materials exhibited CO2 uptake values slightly in excess of theoretical. As the alkyl groups were changed to more sterically hindered secondary or tertiary alkyls, the uptake was less efficient. Heats of absorption values for these materials were generally in the range 2000-2200 kJ/kg of CO2, values significantly lower than those obtained for primary amine functional disiloxanes (2500-2700 kJ/kg of CO2). Also explored were a series of secondary amine functional disiloxanes with X-CH2CH2NH-CH2CH2CH2 - substituents. When X was an electron-donating group (RO-, R2N-, RO-CH2-) the CO2 uptake was also in excess of theoretical. Interestingly, these compounds were generally found to produce carbamate salts that were flowable, low-viscosity oils. Furthermore, the heat of absorption values determined for these materials were even lower. Most compounds gave values below 2000 kJ/kg of CO2. Overall the most promising results were obtained with a methoxyethylaminopropyl derivative, an ethoxyethylaminopropyl-containing material, and a dimethylaminoethylaminopropyl-based compound. These materials showed excellent CO2 uptake, had low heats of absorption, and produced carbamate salts that were flowable liquids even at room temperature.

  14. Variations in product in reactions of naphthoquinone with primary amines

    OpenAIRE

    Barooah Nilotpal; Karmakar Anirban; Singh Marjit W; Baruah Jubaraj B

    2007-01-01

    Abstract Reaction of 1,2-naphthoquinone with primary amines gives a 2-amino-1,4-naphthoquinone derivative which is equivalent to 1,2 to 1,4 carbonyl transposition. For example the reaction of 1,2-naphthoquinone with 4-methoxyaniline gives 2-(4-methoxyanilino)-naphthoquinone-1,4-(4-methoxyanil) (1) and with n-butylamine gives 2-(butylamino)-naphthoquinone-1,4-butylimine (2) respectively. The compounds 1 and 2 are characterized by X-ray crystallography; they have hydrogen-bonded dimeric structu...

  15. Methanogenesis from Methylated Amines in a Hypersaline Algal Mat †

    OpenAIRE

    King, Gary M.

    1988-01-01

    Methane ebullition and high rates of methane production were observed in sediments of a hypersaline pond (180‰) which contained sulfate in excess of 100 mM. The highest rates of methane production were observed in surface sediments associated with an algal mat dominated by a Spirulina sp. The mat contained a methylated amine, glycine betaine (GBT), at levels which accounted for up to 20% of the total mat nitrogen. GBT was apparently the source of trimethylamine (TMA), which was also present i...

  16. Processing method for drained water containing ethanol amine

    International Nuclear Information System (INIS)

    Drained water containing ethanol amine is processed with microorganisms such as hydrazine resistant denitrification bacteria in a biodegrading vessel (A) in the coexistence of nitrous ions and/or nitric ions under an anaerobic condition, and then it is processed with microorganisms such as nitrification bacteria in another biotic oxidation vessel (B) under an aerobic condition to generate the coexistent nitrate ion and/or nitric ion, and returned to the biodegrading vessel (A). Further, they are exposed to air or incorporated with an oxidant and optionally a copper compound such as copper sulfate as a catalyst is added in a step of removing hydrazine. (T.M.)

  17. The application experience of ethanol amine at KORI unit 4

    International Nuclear Information System (INIS)

    The secondary system water chemistry in the KORI PWR units has been well controlled by reducing the corrosion in the tubes of the steam generators; the pH agent has been changing from ammonia to ethanol amine (ETA) (1.8 to 2.0 ppm). For example, the iron concentration in the system was reduced by 40 to 70% compared with ammonia treatment. The paper presents the detailed information, such as ETA injection concentration and the variation of pH, concentration of organic acid products, and irons in the system, and a significant change on sludge after ETA application. (S. Ohno)

  18. The repertoire of trace amine G-protein-coupled receptors

    DEFF Research Database (Denmark)

    Gloriam, David E.; Bjarnadóttir, Thóra K; Yan, Yi-Lin;

    2005-01-01

    Trace amines, such as tyramine, beta-phenylethylamine, tryptamine, and octopamine, are present in trace levels in nervous systems and bind a specific family of G-protein-coupled receptors (GPCR), but the function or origin of this system is not well understood. We searched the genomes of several...... melanogaster), indicating that the ability to bind TA have evolved at least twice in animal evolution. We collected in total over 100 vertebrate TA-receptor sequences, and our phylogenetic analysis shows that several TA-receptors have evolved rapidly with remarkable species variation and that the common...

  19. Biogenic amines and acute thermal stress in the rat

    Science.gov (United States)

    Williams, B. A.; Moberg, G. P.

    1975-01-01

    A study is summarized which demonstrates that depletion of the biogenic amines 5-hydroxytryptamine (5-HT) or norepinephrine (NE) alters the normal thermoregulatory responses to acute temperature stress. Specifically, NE depletion caused a significant depression in equilibrium rectal temperature at 22 C and a greater depression in rectal temperature than controls in response to cold (6 C) stress; NE depletion also resulted in a significantly higher rectal temperature response to acute heat (38 C) stress. Depletion of 5-HT had less severe effects. It remains unclear whether the primary site of action of these agents is central or peripheral.

  20. Pulmonary extraction of biogenic amines during septic shock

    International Nuclear Information System (INIS)

    The effect of live Escherichia coli on the pulmonary extraction of the biogenic amines 14C 5-hydroxytryptamine, (5-HT) and 3H-epinephrine was investigated. The labeled isotopes were injected into a central venous catheter and collected from an aortic catheter. One hundred per cent of the labeled epinephrine was recovered in the control and septic state. Only 32.8 +/- 3.6% SEM of the 5-hydroxytryptamine was recovered before sepsis and 42.5 +/- 4.9% SEM after sepsis. During sepsis, mean arterial pressure fell to 58 mm Hg from 121 mm Hg. Pulmonary shunt increased from .7 +/- .05 SEM to .33 +/- .09 SEM

  1. Extraction of uranium from alkaline medium by certain amines

    International Nuclear Information System (INIS)

    A possible route for treatment of irradiated uranium from alkaline solution was recently addressed. This may have some advantages related to the isolation of many troublesome fission products upon alkaline dissolution of uranium oxides. In this work, the solubility of uranium oxides in alkaline medium of sodium carbonate and sodium hydroxide mixture was investigated. The different factors affecting the solubility were studied. From alkaline solutions, the extraction of uranium by different amines was carried out. The equilibrium encountered in this extraction systems was elaborated. Possible use of these systems for treatment of irradiated uranium was discussed

  2. Preparation of amine coated silver nanoparticles using triethylenetetramine

    Indian Academy of Sciences (India)

    L Ramajo; R Parra; M Reboredo; M Castro

    2009-01-01

    This article presents a simple method towards the preparation of functionalized silver nanoparticles in a continuous medium. Silver nanoparticles were obtained through AgNO3 chemical reduction in ethanol and triethylenetetramine was used to stabilize and functionalize the metal. The product was characterized with X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FTIR), UVvisible spectroscopy, thermal gravimetric analysis (TGA) and transmission electron microscopy (TEM). Monocrystalline silver particles with cubic structure and an average size of 20 nm were obtained. The results reveal that it is possible to synthesize Ag nanoparticles functionalized with amine groups and that particle size is influenced by the processing route.

  3. Carbon nanomaterial based electrochemical sensors for biogenic amines

    International Nuclear Information System (INIS)

    This review describes recent advances in the use of carbon nanomaterials for electroanalytical detection of biogenic amines (BAs). It starts with a short introduction into carbon nanomaterials such as carbon nanotubes, graphene, nanodiamonds, carbon nanofibers, fullerenes, and their composites. Next, electrochemical sensing schemes are discussed for various BAs including dopamine, serotonin, epinephrine, norepinephrine, tyramine, histamine and putrescine. Examples are then given for methods for simultaneous detection of various BAs. Finally, we discuss the current and future challenges of carbon nanomaterial-based electrochemical sensors for BAs. The review contains 175 references. (author)

  4. Electrophilic, Activation-Free Fluorogenic Reagent for Labeling Bioactive Amines.

    Science.gov (United States)

    Sintes, Miquel; De Moliner, Fabio; Caballero-Lima, David; Denning, David W; Read, Nick D; Kielland, Nicola; Vendrell, Marc; Lavilla, Rodolfo

    2016-06-15

    Herein we report the preparation of BODIPY mesoionic acid fluorides through a short sequence involving an isocyanide multicomponent reaction as the key synthetic step. These novel BODIPY acid fluorides are water-stable electrophilic reagents that can be used for the fluorescent derivatization of amine-containing biomolecules using mild and activation-free reaction conditions. As a proof of principle, we have labeled the antifungal natamycin and generated a novel fluorogenic probe for imaging a variety of human and plant fungal pathogens, with excellent selectivity over bacterial cells. PMID:27248580

  5. Mild Metal-Free Hydrosilylation of Secondary Amides to Amines.

    Science.gov (United States)

    Huang, Pei-Qiang; Lang, Qi-Wei; Wang, Yan-Rong

    2016-05-20

    The combination of amide activation by Tf2O with B(C6F5)3-catalyzed hydrosilylation with TMDS constitutes a method for the one-pot reduction of secondary amides to amines under mild conditions. The method displays a broad applicability for the reduction of many types of substrates, and shows good compatibility and excellent chemoselectivity for many sensitive functional groups. Reductions of a multifunctionalized α,β-unsaturated amide obtained from another synthetic methodology, and a C-H functionalization product produced the corresponding amines in good to excellent yield. Chemoselective reduction of enantiomeric pure (ee >99%) tetrahydro-5-oxo-2-furaneamides yielded 5-(aminomethyl)dihydrofuran-2(3H)-ones in a racemization-free manner. The latter were converted in one pot to N-protected 5-hydroxypiperidin-2-ones, which are building blocks for the synthesis of many natural products. Further elaboration of an intermediate led to a concise four-step synthesis of (-)-epi-pseudoconhydrine. PMID:27100232

  6. Analysis of Some Biogenic Amines by Micellar Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Irena Malinowska

    2012-01-01

    Full Text Available Micellar liquid chromatography (MLC with the use of high performance liquid chromatography (HPLC was used to determine some physicochemical parameters of six biogenic amines: adrenaline, dopamine, octopamine, histamine, 2-phenylethylamine, and tyramine. In this paper, an influence of surfactant’s concentration and pH of the micellar mobile phase on the retention of the tested substances was examined. To determine the influence of surfactant’s concentration on the retention of the tested amines, buffered solutions (at pH 7.4 of ionic surfactant—sodium dodecyl sulfate SDS (at different concentrations with acetonitrile as an organic modifier (0.8/0.2 v/v were used as the micellar mobile phases. To determine the influence of pH of the micellar mobile phase on the retention, mobile phases contained buffered solutions (at different pH values of sodium dodecyl sulfate SDS (at 0.1 M with acetonitrile (0.8/0.2 v/v. The inverse of value of retention factor (1/ versus concentration of micelles ( relationships were examined. Other physicochemical parameters of solutes such as an association constant analyte—micelle (ma—and partition coefficient of analyte between stationary phase and water (hydrophobicity descriptor (swΦ were determined by the use of Foley’s equation.

  7. Factors influencing biogenic amines accumulation in dairy products.

    Science.gov (United States)

    Linares, Daniel M; Del Río, Beatriz; Ladero, Victor; Martínez, Noelia; Fernández, María; Martín, María Cruz; Alvarez, Miguel A

    2012-01-01

    Fermented foods are among the food products more often complained of having caused episodes of biogenic amines (BA) poisoning. Concerning milk-based fermented foods, cheese is the main product likely to contain potentially harmful levels of BA, specially tyramine, histamine, and putrescine. Prompted by the increasing awareness of the risks related to dietary uptake of high biogenic amine loads, in this review we report all those elaboration and processing technological aspects affecting BA biosynthesis and accumulation in dairy foods. Improved knowledge of the factors involved in the synthesis and accumulation of BA should lead to a reduction in their incidence in milk products. Synthesis of BA is possible only when three conditions converge: (i) availability of the substrate amino acids; (ii) presence of microorganisms with the appropriate catabolic pathway activated; and (iii) environmental conditions favorable to the decarboxylation activity. These conditions depend on several factors such as milk treatment (pasteurization), use of starter cultures, NaCl concentration, time, and temperature of ripening and preservation, pH, temperature, or post-ripening technological processes, which will be discussed in this chapter. PMID:22783233

  8. BIODEGRADATION OF AROMATIC AMINE COMPOUNDS USING MOVING BED BIOFILM REACTORS

    Directory of Open Access Journals (Sweden)

    M. Delnavaz ، B. Ayati ، H. Ganjidoust

    2008-10-01

    Full Text Available Three moving bed biofilm reactors were used to treat synthesized wastewater of aromatic amine compounds including aniline, para-diaminobenzene and para-aminophenol that are found in many industrial wastewaters. The reactors with cylindrical shape had an internal diameter and an effective depth of 10 and 60 cm, respectively. The reactors were filled with light expanded clay aggregate as carriers and operated in an aerobic batch and continuous conditions. Evaluation of the reactors' efficiency was done at different retention time of 8, 24, 48 and 72 h with an influent COD from 100 to 3500 mg/L (filling ratio of 50%. The maximum obtained removal efficiencies were 90% (influent COD=2000 mg/L, 87% (influent COD=1000 mg/L and 75% (influent COD=750 mg/L for aniline, para-diaminobenzene and para-aminophenol, respectively. In the study of decrease in filling ratio from 50 to 30 percent, 6% decrease for both para-diaminobenzene and para-aminophenol and 7% increase for aniline degradation were obtained. The removal efficiency was decreased to about 10% after 15 days of continuous loading for each of the above three substrates. In the shock loading test, initially the COD removal rate was decreased in all reactors, but after about 10 days, it has been approached to the previous values. Finally, biodegradability of aromatic amines has been proved by nuclear magnetic resonance system.

  9. Analysis of irradiated biogenic amines by computational chemistry and spectroscopy

    International Nuclear Information System (INIS)

    Biogenic Amines (B A) are nitrogenous compounds able to cause food poisoning. In this work, we studied the tyramine, one of the most common BA present in foods by combining experimental measured IR (Infrared) and GC/MS (Gas Chromatograph / Mass Spectrometry) spectra and computational quantum chemistry. Density Functional Theory (DFT) and the Deformed Atoms in Molecules (DMA) method was used to compute the partition the electronic densities in a chemically-intuitive way and electrostatic potentials of molecule to identify the acid and basic sites. Trading pattern was irradiated using a Cs 137 radiator, and each sample was identified by IR and GC/MS. Calculated and experimental IR spectra were compared. We observed that ionizing gamma irradiation was very effective in decreasing the population of standard amine, resulting in fragments that could be rationalized through the quantum chemistry calculations. In particular, we could locate the acid and basic sites of both molecules and identify possible sites of structural weaknesses, which allowed to propose mechanistic schemes for the breaking of chemical bonds by the irradiation. Moreover, from this work we hope it will be also possible to properly choose the dose of gamma irradiation which should be provided to eliminate each type of contamination. (author)

  10. Analysis of biogenic amines using corona discharge ion mobility spectrometry.

    Science.gov (United States)

    Hashemian, Z; Mardihallaj, A; Khayamian, T

    2010-05-15

    A new method based on corona discharge ion mobility spectrometry (CD-IMS) was developed for the analysis of biogenic amines including spermidine, spermine, putrescine, and cadaverine. The ion mobility spectra of the compounds were obtained with and without n-Nonylamine used as the reagent gas. The high proton affinity of n-Nonylamine prevented ion formation from compounds with a proton affinity lower than that of n-Nonylamine and, therefore, enhanced its selectivity. It was also realized that the ion mobility spectrum of n-Nonylamine varied with its concentration. A sample injection port of a gas chromatograph was modified and used as the sample introduction system into the CD-IMS. The detection limits, dynamic ranges, and analytical parameters of the compounds with and without using the reagent gas were obtained. The detection limits and dynamic ranges of the compounds were about 2ng and 2 orders of magnitude, respectively. The wide dynamic range of CD-IMS originates from the high current of the corona discharge. The results revealed the high capability of the CD-IMS for the analysis of biogenic amines. PMID:20298897

  11. Substrate specificity of copper-containing plant amine oxidases.

    Science.gov (United States)

    Pietrangeli, P; Federico, R; Mondovì, B; Morpurgo, L

    2007-07-01

    The steady-state kinetic parameters of the amine oxidases purified from Lathyrus cicera (LCAO) and Pisum sativum (PSAO) seedling were measured on a series of common substrates, previously tested on bovine serum amine oxidase (BSAO). LCAO, as PSAO, was substantially more reactive than BSAO with aliphatic diamines and histamine. The k(cat) and k(cat)/Km for putrescine were four and six order of magnitude higher, respectively. Differences were smaller with some aromatic monoamines. The plot of k(cat) versus hydrogen ions concentration produced bell-shaped curves, the maximum of which was substrate dependent, shifting from neutral pH with putrescine to alkaline pH with phenylethylamine and benzylamine. The latter substrates made the site more hydrophobic and increased the pK(a) of both enzyme-substrate and enzyme-product adducts. The plot of k(cat)/Km versus hydrogen ion concentration produced approximately parallel bell-shaped curves. Similar pK(a) couples were obtained from the latter curves, in agreement with the assignment as free enzyme and free substrate pK(a). The limited pH dependence of kinetic parameters suggests a predominance of hydrophobic interactions. PMID:17521737

  12. Amine-oxide hybrid materials for acid gas separations

    KAUST Repository

    Bollini, Praveen

    2011-01-01

    Organic-inorganic hybrid materials based on porous silica materials functionalized with amine-containing organic species are emerging as an important class of materials for the adsorptive separation of acid gases from dilute gas streams. In particular, these materials are being extensively studied for the adsorption of CO 2 from simulated flue gas streams, with an eye towards utilizing these materials as part of a post-combustion carbon capture process at large flue gas producing installations, such as coal-fired electricity-generating power plants. In this Application Article, the utilization of amine-modified organic-inorganic hybrid materials is discussed, focusing on important attributes of the materials, such as (i) CO 2 adsorption capacities, (ii) adsorption and desorption kinetics, and (iii) material stability, that will determine if these materials may one day be useful adsorbents in practical CO 2 capture applications. Specific research needs and limitations associated with the current body of work are identified. © 2011 The Royal Society of Chemistry.

  13. Application of ultraviolet, ozone, and advanced oxidation treatments to washwaters to destroy nitrosamines, nitramines, amines, and aldehydes formed during amine-based carbon capture.

    Science.gov (United States)

    Shah, Amisha D; Dai, Ning; Mitch, William A

    2013-03-19

    Although amine-based CO(2) absorption is a leading contender for full-scale postcombustion CO(2) capture at power plants, concerns have been raised about the potential release of carcinogenic N-nitrosamines and N-nitramines formed by reaction of exhaust gas NO(x) with the amines. Experiments with a laboratory-scale pilot unit suggested that washwater units meant to scrub contaminants from absorber unit exhaust could potentially serve as a source of N-nitrosamines via reactions of residual NO(x) with amines accumulating in the washwater. Dosage requirements for the continuous treatment of the washwater recycle line with ultraviolet (UV) light for destruction of N-nitrosamines and N-nitramines, and with ozone or hydroxyl radical-based advanced oxidation processes (AOPs) for destruction of amines and aldehydes, were evaluated. Although cost estimates would require pilot testing to capture synergies between UV and ozone treatments. PMID:23425146

  14. Rôle des acides aminés dans la production d'amines biogènes chez Oenococcus oeni

    OpenAIRE

    Dandach, Said,

    2013-01-01

    Dans le vin, les amines biogènes sont essentiellement d'origine microbienne, et sont produitesnotamment par les bactéries lactiques Oenococcus oeni, principal agent responsable de lafermentation malolactique, possède de nombreuses auxotrophies vis-à-vis des acides aminés.Aucune étude n'a été menée sur la relation entre l’auxotrophie vis-à-vis d’un acide aminé et leniveau de l’amine correspondante. 80 souches de Oenococcus oeni ont été isolées de vinsrouges. Leurs auxotrophies vis-à-vis d’acid...

  15. Amination of Aryl Halides and Esters Using Intensified Continuous Flow Processing

    OpenAIRE

    Thomas M. Kohl; Christian H. Hornung; John Tsanaktsidis

    2015-01-01

    Significant process intensification of the amination reactions of aryl halides and esters has been demonstrated using continuous flow processing. Using this technology traditionally difficult amination reactions have been performed safely at elevated temperatures. These reactions were successfully conducted on laboratory scale coil reactor modules with 1 mm internal diameter (ID) and on a preparatory scale tubular reactor with 6 mm ID containing static mixers.

  16. Nucleophilic addition of amines to the activated ethylene bond in non-aqueous media

    International Nuclear Information System (INIS)

    The kinetics of addition of a number of primary and secondary aliphatic amines to trans-(2-furyl) nitro ethylene (1) has been studied in solvents of various polarities (from acetonitrile, ε 37.5, to heptane, ε 1.89). It has been shown that the reaction is catalysed both by the amine reagent and by tertiary amines. On the basis of analyzing the observed kinetic regularities a stepwise reaction mechanism has been proposed which involves formation of zwitterionic intermediate (3) at the first equilibrium step (k1, K1) which is then converted into the reaction product by means of proton transfer in parallel routes, the non-catalytic one (k2) and that catalysed by the initial (K3) or tertiary (K4) amine. The observed high values of the deuterium isotope effects in the reaction (KH/KD ∼ 2.3 - 8.9) confirm that proton transfer occurs in the rate-limiting step of the reaction (primary kinetic isotope effect). The third order by amine kinetic route is observed in low polar media which is due to participation of amine dimers (R2 NH HNR2) in the reaction. The observed kinetic regularities are compared with those for the nucleophilic aromatic substitution reactions in low-polar media, and the conclusion has been made that the reaction route of the third order by amine proceeds as reversible nucleophilic attack by amine dimer and following base-catalysed transformation of the intermediate into the product. (author)

  17. Iridium‐Catalyzed Condensation of Amines and Vicinal Diols to Substituted Piperazines

    DEFF Research Database (Denmark)

    Lorentz-Petersen, Linda Luise Reeh; Nordstrøm, Lars Ulrik Rubæk; Madsen, Robert

    2012-01-01

    is believed to involve dehydrogenation of the 1,2‐diol to the α‐hydroxy aldehyde, which condenses with the amine to form the α‐hydroxy imine. The latter rearranges to the corresponding α‐amino carbonyl compound, which then reacts with another amine followed by reduction of the resulting imine....

  18. N-heterocyclic carbene copper(I) catalysed N-methylation of amines using CO2

    KAUST Repository

    Santoro, Orlando

    2015-09-30

    The N-methylation of amines using CO2 and PhSiH3 as source of CH3 was efficiently performed using a N-heterocyclic carbene copper(I) complex. The methodology was found compatible with aromatic and aliphatic primary and secondary amines. Synthetic and computational studies have been carried out to support the proposed reaction mechanism for this transformation.

  19. Concentration of Biogenic Amines in ‘Pinot Noir’ Wines Produced in Croatia

    Directory of Open Access Journals (Sweden)

    Ana Jeromel

    2012-03-01

    Full Text Available The origins of biogenic amines are sound grapes, alcoholic fermentations, malolactic fermentation and microbial activities during wine storage. These biologically produced amines are essential at low concentrations for optimal metabolic and physiological functions in animals, plants and micro-organisms. During alcoholic fermentation the degree of maceration is the first factor that affects the extraction of compounds present in the grape skin, among them aminoacids, precursors of biogenic amines. The aim of the present work was to study the changes of the concentration of biogenic amines in wines made from Vitis vinifera ‘Pinot noir’ from Plešivica (vintage 2009 produced with classical maceration, cold maceration and use of sur lie method. Biogenic amines were quantified using a reversed-phase high performance liquid chromatography (HPLC with fluorescence detection after pre-column derivatization with o-phthalaldehyde (OPA. In ‘Pinot noir’ wines tested, histamine was the most abundant biogenic amine followed by tryptamine and 2-Phenylethylamine. Total amount of biogenic amines ranged from 8.72 mg/L in wines made with classical maceration up to 9.34 mg/L in sur lie wines. In summary, from the results obtained in this study, it can be concluded that sur lie technology can influence the formation of biogenic acids since the release of amino acids is probably more pronounced in wines aged with lees and stirred weekly. No significant differences were found in the concentration of biogenic amines in relation to the used maceration process.

  20. Expedient protocol for solid-phase synthesis of secondary and tertiary amines

    DEFF Research Database (Denmark)

    Olsen, Christian A; Witt, Matthias; Jaroszewski, Jerzy W; Franzyk, Henrik

    2004-01-01

    [reaction: see text] An expedient solid-phase synthetic approach to secondary and tertiary amines was developed. The protocol employs conversion of resin-bound amino alcohols to the corresponding iodides, followed by iodide displacement with primary or secondary amines or with unprotected amino...

  1. Genome Sequence Analysis of the Biogenic Amine-Degrading Strain Lactobacillus casei 5b

    OpenAIRE

    Ladero Losada, Víctor Manuel; Herrero, Ana; Martínez Álvarez, Noelia; Río Lagar, Beatriz del; Linares, Daniel M.; Fernández García, María; Martín, M. Cruz; Álvarez González, Miguel Ángel

    2014-01-01

    We here report a 3.02-Mbp annotated draft assembly of the Lactobacillus casei 5b genome. The sequence of this biogenic amine-degrading dairy isolate may help identify the mechanisms involved in the catabolism of biogenic amines and perhaps shed light on ways to reduce the presence of these toxic compounds in food.

  2. Differential behavioral responses of two plant-parasitic nematodes to biogenic amines

    Science.gov (United States)

    Hatching and infective juvenile (J2) behavior in two species of plant-parasitic nematodes, Heterodera glycines and Meloidogyne incognita, were affected by in vitro treatment with the biogenic amines dopamine, octopamine, and serotonin. While the overall responses of each species to amine exposures w...

  3. Concentration of Biogenic Amines in ‘Pinot Noir’ Wines Produced in Croatia

    Directory of Open Access Journals (Sweden)

    Ana Jeromel

    2014-02-01

    Full Text Available The origins of biogenic amines are sound grapes, alcoholic fermentations, malolactic fermentation and microbial activities during wine storage. These biologically produced amines are essential at low concentrations for optimal metabolic and physiological functions in animals, plants and micro-organisms. During alcoholic fermentation the degree of maceration is the first factor that affects the extraction of compounds present in the grape skin, among them aminoacids, precursors of biogenic amines. The aim of the present work was to study the changes of the concentration of biogenic amines in wines made from Vitis vinifera ‘Pinot noir’ from Plešivica (vintage 2009 produced with classical maceration, cold maceration and use of sur lie method. Biogenic amines were quantified using a reversed-phase high performance liquid chromatography (HPLC with fluorescence detection after pre-column derivatization with o-phthalaldehyde (OPA. In ‘Pinot noir’ wines tested, histamine was the most abundant biogenic amine followed by tryptamine and 2-Phenylethylamine. Total amount of biogenic amines ranged from 8.72 mg/L in wines made with classical maceration up to 9.34 mg/L in sur lie wines. In summary, from the results obtained in this study, it can be concluded that sur lie technology can influence the formation of biogenic acids since the release of amino acids is probably more pronounced in wines aged with lees and stirred weekly. No significant differences were found in the concentration of biogenic amines in relation to the used maceration process.

  4. Long-chain amine-templated synthesis of gallium sulfide and gallium selenide nanotubes

    Science.gov (United States)

    Seral-Ascaso, A.; Metel, S.; Pokle, A.; Backes, C.; Zhang, C. J.; Nerl, H. C.; Rode, K.; Berner, N. C.; Downing, C.; McEvoy, N.; Muñoz, E.; Harvey, A.; Gholamvand, Z.; Duesberg, G. S.; Coleman, J. N.; Nicolosi, V.

    2016-06-01

    We describe the soft chemistry synthesis of amine-templated gallium chalcogenide nanotubes through the reaction of gallium(iii) acetylacetonate and the chalcogen (sulfur, selenium) using a mixture of long-chain amines (hexadecylamine and dodecylamine) as a solvent. Beyond their role as solvent, the amines also act as a template, directing the growth of discrete units with a one-dimensional multilayer tubular nanostructure. These new materials, which broaden the family of amine-stabilized gallium chalcogenides, can be tentatively classified as direct large band gap semiconductors. Their preliminary performance as active material for electrodes in lithium ion batteries has also been tested, demonstrating great potential in energy storage field even without optimization.We describe the soft chemistry synthesis of amine-templated gallium chalcogenide nanotubes through the reaction of gallium(iii) acetylacetonate and the chalcogen (sulfur, selenium) using a mixture of long-chain amines (hexadecylamine and dodecylamine) as a solvent. Beyond their role as solvent, the amines also act as a template, directing the growth of discrete units with a one-dimensional multilayer tubular nanostructure. These new materials, which broaden the family of amine-stabilized gallium chalcogenides, can be tentatively classified as direct large band gap semiconductors. Their preliminary performance as active material for electrodes in lithium ion batteries has also been tested, demonstrating great potential in energy storage field even without optimization. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01663d

  5. Asymmetric α-amination of β-keto esters using a guanidine–bisurea bifunctional organocatalyst

    Science.gov (United States)

    Yamamoto, Yoshiharu

    2016-01-01

    Summary An asymmetric α-amination of β-keto esters with azodicarboxylate in the presence of a guanidine–bisurea bifunctional organocatalyst was investigated. The α-amination products were obtained in up to 99% yield with up to 94% ee. PMID:26977179

  6. Plasma semicarbazide-sensitive amine oxidase is elevated in patients with congestive heart failure

    NARCIS (Netherlands)

    Boomsma, F; vanVeldhuisen, DJ; deKam, PJ; ManintVeld, AJ; Mosterd, A; Lie, KI; Schalekamp, MADH

    1997-01-01

    Objective: Semicarbazide-sensitive amine oxidase (SSAO) is present in various mammalian tissues, especially in vascular smooth muscle cells, but also in plasma. The enzyme has been suggested to play a role in vascular endothelial damage through conversion of amines into cytotoxic aldehydes, ammonia

  7. The Petasis Reaction: Microscale Synthesis of a Tertiary Amine Antifungal Analog

    Science.gov (United States)

    Koroluk, Katherine J.; Jackson, Derek A.; Dicks, Andrew P.

    2012-01-01

    Students prepare a tertiary amine antifungal analog in an upper-level undergraduate organic laboratory. A microscale Petasis reaction is performed to generate a liquid compound readily characterized via IR and proton NMR spectroscopy. The biological relevance of the product is highlighted, with the tertiary amine scaffold being an important…

  8. Extension of the cubic-plus-association (CPA) equation of state to amines

    DEFF Research Database (Denmark)

    Kaarsholm, Mads Kristian; Derawi, Samer; Michelsen, Michael Locht; Kontogeorgis, Georgios

    2005-01-01

    The cubic-plus-association (CPA) equation of state has been extended to modeling mixtures containing amines. Special focus was given to primary and secondary amines, which are known to self-associate, thus forming hydrogen bonds in mixtures with alkanes. Pure-compound parameters have been...

  9. Facile one-pot synthesis of unsymmetrical ureas, carbamates, and thiocarbamates from Cbz-protected amines.

    Science.gov (United States)

    Kim, Hee-Kwon; Lee, Anna

    2016-07-26

    A novel one-pot synthesis of unsymmetrical ureas, carbamates and thiocarbamates from Cbz-protected amines has been developed. In the presence of 2-chloropyridine and trifluoromethanesulfonyl anhydride, isocyanates are generated in situ, which facilitate rapid reaction with amines, alcohols, and thiols to afford the corresponding ureas, carbamates and thiocarbamates in high yields. PMID:27406041

  10. Enhanced reactivities toward amines by introducing an imine arm to the pincer ligand: Direct coupling of two amines to form an imine without oxidant

    KAUST Repository

    He, Lipeng

    2012-07-23

    Dehydrogenative homocoupling of primary alcohols to form esters and coupling of amines to form imines was accomplished using a class of novel pincer ruthenium complexes. The reactivities of the ruthenium pincer complexes for the direct coupling of amines to form imines were enhanced by introducing an imine arm to the pincer ligand. Selective oxidation of benzylamines to imines was achieved using aniline derivatives as the substrate and solvent. © 2012 American Chemical Society.

  11. In Situ Preparation of Polyether Amine Functionalized MWCNT Nanofiller as Reinforcing Agents

    Directory of Open Access Journals (Sweden)

    Ayber Yıldrım

    2014-01-01

    Full Text Available In situ preparation of polyether amine functionalized cross-linked multiwalled carbon nanotube (MWCNT nanofillers may improve the thermal and mechanical properties of the composites in which they are used as reinforcing agents. The reduction and functionalization of MWCNT using ethylenediamine in the presence of polyether amine produced stitched MWCNT's due to the presence of two amine (–NH2 functionalities on both sides of the polymer. Polyether amine was chosen to polymerize the carboxylated MWCNT due to its potential to form bonds with the amino groups and carboxyl groups of MWCNT which produces a resin used as polymeric matrix for nanocomposite materials. The attachment of the polyether amine (Jeffamine groups was verified by TGA, FT-IR, XRD, SEM, and Raman spectroscopy. The temperature at which the curing enthalpy is maximum, observed by DSC, was shifted to higher values by adding functionalized MWCNT. SEM images show the polymer formation between MWCNT sheets.

  12. Amine synthesis via iron-catalysed reductive coupling of nitroarenes with alkyl halides.

    Science.gov (United States)

    Cheung, Chi Wai; Hu, Xile

    2016-01-01

    (Hetero)Aryl amines, an important class of organic molecules in medicinal chemistry, are most commonly synthesized from anilines, which are in turn synthesized by hydrogenation of nitroarenes. Amine synthesis directly from nitroarenes is attractive due to improved step economy and functional group compatibility. Despite these potential advantages, there is yet no general method for the synthesis of (hetero)aryl amines by carbon-nitrogen cross-coupling of nitroarenes. Here we report the reductive coupling of nitroarenes with alkyl halides to yield (hetero)aryl amines. A simple iron catalyst enables the coupling with numerous primary, secondary and tertiary alkyl halides. Broad scope and high functional group tolerance are demonstrated. Mechanistic study suggests that nitrosoarenes and alkyl radicals are involved as intermediates. This new C-N coupling method provides general and step-economical access to aryl amines. PMID:27515391

  13. Alteration of the Donor/Acceptor Spectrum of the (S-Amine Transaminase from Vibrio fluvialis

    Directory of Open Access Journals (Sweden)

    Maika Genz

    2015-11-01

    Full Text Available To alter the amine donor/acceptor spectrum of an (S-selective amine transaminase (ATA, a library based on the Vibrio fluvialis ATA targeting four residues close to the active site (L56, W57, R415 and L417 was created. A 3DM-derived alignment comprising fold class I pyridoxal-5′-phosphate (PLP-dependent enzymes allowed identification of positions, which were assumed to determine substrate specificity. These positions were targeted for mutagenesis with a focused alphabet of hydrophobic amino acids to convert an amine:α-keto acid transferase into an amine:aldehyde transferase. Screening of 1200 variants revealed three hits, which showed a shifted amine donor/acceptor spectrum towards aliphatic aldehydes (mainly pentanal, as well as an altered pH profile. Interestingly, all three hits, although found independently, contained the same mutation R415L and additional W57F and L417V substitutions.

  14. Determination of oxyfluorfen herbicide and oxyfluorfen amine residues in garbanzo beans by liquid chromatography.

    Science.gov (United States)

    Zhou, M; Miles, C J

    1991-01-01

    Oxyfluorfen and oxyfluorfen amine were determined by liquid chromatography (LC) with ultraviolet (UV) and photoconductivity detection (PCD). A simple extraction procedure acceptably recovered both analytes from garbanzo beans over a wide range of fortifications (0.05 to 20 ppm) (83 +/- 4 for oxyfluorfen; 85 +/- 4 for oxyfluorfen amine). Percent recoveries decreased slightly as the fortification level decreased. Both analytes could be determined simultaneously at a concentration greater than 0.2 ppm in garbanzo beans. Detection limits were 3 ng for oxyfluorfen and 100 ng for oxyfluorfen amine using LC/UV, and 12 ng for both oxyfluorfen and oxyfluorfen amine with LC/PCD. Different knitted reaction coils and photoreactors were evaluated. Photoproduct yields and identification were determined by ion chromatography. The LC/PCD method measures oxyfluorfen and oxyfluorfen amine separately and has a shorter analysis time, while the standard method using gas chromatography measures total residues and is more sensitive. PMID:1874702

  15. Observation of the wrapping mechanism in amine carbon dioxide molecular interactions on heterogeneous sorbents.

    Science.gov (United States)

    Thirion, D; Rozyyev, V; Park, J; Byun, J; Jung, Y; Atilhan, M; Yavuz, C T

    2016-06-01

    Liquid, solvated amine based carbon capture is the core of all commercial or planned CO2 capture operations. Despite the intense research, few have looked systematically into the nature of amine molecules and their CO2 interaction. Here, we report a systematic introduction of linear ethylene amines on the walls of highly porous Davankov type network structures through simple bromination intermediates. Surprisingly, isosteric heats of CO2 adsorption show a clear linear trend with the increase in the length of the tethered amine pendant groups, leading to a concerted cooperative binding with additional H-bonding contributions from the unassociated secondary amines. CO2 uptake capacities multiply with the nitrogen content, up to an unprecedented four to eight times of the starting porous network under flue gas conditions. The reported procedure can be generalized to all porous media with the robust hydrocarbon framework in order to convert them into effective CO2 capture adsorbents. PMID:27174155

  16. Characterization of molybdenum interfacial crud in a uranium mill that employs tertiary-amine solvent extraction

    International Nuclear Information System (INIS)

    In the present work, samples of a molybdenum-caused green gummy interfacial crud from an operating western US uranium mill have been physically and chemically examined. Formaton of cruds of this description has been a long-standing problem in the use of tertiary amine solvent extraction for the recovery of uranium from low-grade ores (Amex Process). The crud is essentially an organic-continuous dispersion containing about 10 wt % aqueous droplets and about 37 wt % greenish-yellow crystalline solids suspended in kerosene-amine process solvent. The greenish-yellow crystals were found to be a previously unknown double salt of tertiary amine molybdophosphate with three tertiary amine chlorides having the empirical formula (R3NH)3[PMo12O40].3(R3NH)Cl. To confirm the identification of the compound, a pure trioctylamine (TOA) analog was synthesized. In laboratory extraction experiments, it was demonstrated that organic-soluble amine molydophosphate forms slowly upon contact of TOA solvent with dilute sulfuric acid solutions containing low concentrations of molybdate and phosphate. If the organic solutions of amine molybdophosphate were then contacted with aqueous NaCl solutions, a greenish-yellow precipitate of (TOAH)3[PMo12O40].3(TOAH)Cl formed at the interface. The proposed mechanism for the formation of the crud under process conditions involves build up of molybdenum in the solvent, followed by reaction with extracted phosphate to give dissolved amine molybdophosphate. The amine molybdophosphate then co-crystallizes with amine chloride, formed during the stripping cycle, to give the insoluble double salt, which precipitates as a layer of small particles at the interface. The proposed solution to the problem is the use of branched-chain, instead of straight-chain, tertiary amine extractants under the expectation that branching would increase the solubility of the double salt. 2 figures, 5 tables

  17. Observation of neutral sulfuric acid-amine containing clusters in laboratory and ambient measurements

    Directory of Open Access Journals (Sweden)

    J. Zhao

    2011-11-01

    Full Text Available Recent ab initio calculations showed that amines can enhance atmospheric sulfuric acid-water nucleation more effectively than ammonia, and this prediction has been substantiated in laboratory measurements. Laboratory studies have also shown that amines can effectively displace ammonia in several types of ammonium clusters. However, the roles of amines in cluster formation and growth at a microscopic molecular scale (from molecular sizes up to 2 nm have not yet been well understood. Processes that must be understood include the incorporation of amines into sulfuric acid clusters and the formation of organic salts in freshly nucleated particles, which contributes significantly to particle growth rates. We report the first laboratory and ambient measurements of neutral sulfuric acid-amine clusters using the Cluster CIMS, a recently-developed mass spectrometer designed for measuring neutral clusters formed in the atmosphere during nucleation. An experimental technique, which we refer to as Semi-Ambient Signal Amplification (SASA, was employed. Sulfuric acid was added to ambient air, and the concentrations and composition of clusters in this mixture were analyzed by the Cluster CIMS. This experimental approach led to significantly higher cluster concentrations than are normally found in ambient air, thereby increasing signal-to-noise levels and allowing us to study reactions between gas phase species in ambient air and sulfuric acid containing clusters. Mass peaks corresponding to clusters containing four H2SO4 molecules and one amine molecule were clearly observed, with the most abundant sulfuric acid-amine clusters being those containing a C2- or C4-amine (i.e. amines with masses of 45 and 73 amu. Evidence for C3- and C5-amines (i.e. amines with masses of 59 and 87 amu was also found, but their correlation with sulfuric acid tetramer was not as strong as was observed for the C2- and C4-amines. The formation mechanisms for

  18. Enthalpy of cooperative hydrogen bonding in complexes of tertiary amines with aliphatic alcohols: Calorimetric study

    International Nuclear Information System (INIS)

    Research highlights: → Solution enthalpies of aliphatic alcohols in tertiary amines and vice versa were measured. → The enthalpies of specific interaction of amines in aliphatic alcohols are lower than the enthalpies of hydrogen bonding in 1:1 complexes amine-alcohol determined in base media. → Hydrogen bond cooperativity factors in multi-particle complexes of alcohols with aromatic amines are approximately equal for all alcohols. → Hydrogen bond cooperativity factors in multi-particle complexes of alcohols with trialkylamines decrease with increasing of alkyl radical length in alcohol and amine molecules. - Abstract: The work is devoted to the investigation of thermodynamics of specific interaction of the tertiary aliphatic and aromatic amines with associated solvents as which aliphatic alcohols were taken. Solution enthalpies of aliphatic alcohols in amines (tri-n-propylamine, 2-methylpyridine, 3-methylpyridine, N-methylimidazole) as well as amines in alcohols were measured at infinite dilution. The enthalpies of specific interaction (H-bonding) in systems studied were determined based on experimental data. The enthalpies of specific interaction of amines in aliphatic alcohols significantly lower than the enthalpies of hydrogen bonding in complexes amine-alcohol of 1:1 composition determined in base media due to the reorganization of aliphatic alcohols as solvents. The determination of solvent reorganization contribution makes possible to define the hydrogen bonding enthalpies of amines with clusters of alcohols. Obtained enthalpies of hydrogen bonding in multi-particle complexes are sensitive to the influence of cooperative effect. It was shown, that hydrogen bond cooperativity factors in multi-particle complexes of alcohols with amines are approximately equal for all alcohols when pyridines and N-methylimidazole as solutes are used. At the same time, H-bonding cooperativity factors in complexes of trialkylamines with associative species of alcohols

  19. New insights into controlling tube-bundle fouling using alternative amines

    International Nuclear Information System (INIS)

    A volatile amine is added to the secondary heat-transport system of a nuclear power plant to reduce the rate of corrosion and corrosion product transport in the feedwater and to protect steam generator (SG) crevices and materials exposed to steam condensate. Volatility and base strength of the amine at the SG operating temperature are two important considerations when choosing the optimum amine (or mixture of amines) for corrosion control in the steam cycle. The investigation has found that the rate of tube-bundle fouling is strongly dependent upon the surface chemistry of the corrosion products. For example, the fouling rates of fully oxidized iron oxides, such as hematite and lepidocrocite, are at least an order of magnitude greater than the fouling rate of magnetite under identical operating conditions. The difference is related to the sign of the surface charge on the corrosion products at temperature. The choice of amine for pH-control also influences the fouling rate. This was originally thought to be a surface-charge effect as well, but recent tests have suggested that it is related to the role that the amine plays in governing the rate of deposit consolidation on the heat-transfer surface. Amines that promote a high rate of deposit consolidation result in a low rate of deposit removal and a high fouling rate. Conversely, amines that tend to inhibit deposit consolidation produce a higher rate of deposit removal and a lower fouling rate. Dimethyl-amine and dodecyl-amine have been identified as two amines that inhibit the rate of deposit consolidation and, consequently, result in fouling rates that are up to 5 times lower than rates measured for amines that promote consolidation. A significant difference between morpholine (high fouling rate) and dimethyl-amine (low fouling rate) is that the latter desorbs more slowly from the surface of magnetite. How to account for a correlation between slow desorption kinetics and lower rate constants for deposition and

  20. Amine coupling through EDC/NHS: a practical approach.

    Science.gov (United States)

    Fischer, Marcel J E

    2010-01-01

    Surface plasmon resonance (SPR) is one of the leading tools in biomedical research. The challenge in its use is the controlled positioning of one of the components of an interaction on a carefully designed surface. Many attempts in interaction analysis fail due to the non-functional or unsuccessful immobilization of a reactant onto the complex matrix of that surface. The most common technique for linking ligands covalently to a hydrophilic solid surface is amine coupling via reactive esters. In this chapter detailed methods and problem discussions will be given to assist in fast decision analysis to optimize immobilization and regeneration. Topics in focus are different coupling techniques for small and large molecules, streptavidin-biotin sandwich immobilization, and optimizing regeneration conditions. PMID:20217613

  1. Synthesis of allyl amine on glass by continuous plasma

    International Nuclear Information System (INIS)

    In this work the synthesis by plasma of thin films of polyallyl amine under continuous plasma conditions for possible use in biomaterials is presented. It is shown that the thickness of the film depends so much of the time of synthesis like of the used power. The polymers were analyzed by X-ray photoelectron spectroscopy (XPS) and angle of contact before and after of being immersed in distilled water by 10 days. The allylamine shows lost of nitrogen and an increase in the content of oxygen with the immersion time due to the interaction among the water and the polymer. The angle of contact shows an increase of approximately 10 degrees, what indicates a change in the surface energy of the polymer. (Author)

  2. Thermodynamics of organic mixtures containing amines. VIII. Systems with quinoline

    International Nuclear Information System (INIS)

    (Solid + liquid) equilibrium temperatures for mixtures containing quinoline and 1-dodecanol, 1-hexadecanol, or 1-octadecanol have been measured using a dynamic method. (Quinoline + benzene, +alkane, or +1-alkanol) systems were investigated using DISQUAC. The corresponding interaction parameters are reported. The model yields a good representation of molar excess Gibbs free energies, GE, molar excess enthalpies, HE, and of the (solid + liquid) equilibria, SLE. Interactional and structural effects were analysed comparing HE and the molar excess internal energy at constant volume, UVE. It was encountered that structural effects are very important in systems involving alkanes or 1-alkanols. Interactions between amine molecules are stronger in mixtures with quinoline than in those containing pyridine, which was ascribed to the higher polarizability of quinoline

  3. Highly Aminated Mesoporous Silica Nanoparticles with Cubic Pore Structure

    KAUST Repository

    Suteewong, Teeraporn

    2011-01-19

    Mesoporous silica with cubic symmetry has attracted interest from researchers for some time. Here, we present the room temperature synthesis of mesoporous silica nanoparticles possessing cubic Pm3n symmetry with very high molar ratios (>50%) of 3-aminopropyl triethoxysilane. The synthesis is robust allowing, for example, co-condensation of organic dyes without loss of structure. By means of pore expander molecules, the pore size can be enlarged from 2.7 to 5 nm, while particle size decreases. Adding pore expander and co-condensing fluorescent dyes in the same synthesis reduces average particle size further down to 100 nm. After PEGylation, such fluorescent aminated mesoporous silica nanoparticles are spontaneously taken up by cells as demonstrated by fluorescence microscopy.

  4. Thermodynamics of organic mixtures containing amines. VIII. Systems with quinoline

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F., Grupo Especializado en Termodinamica de Equilibrio entre Fases, Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, E-47071 Valladolid (Spain)], E-mail: jagl@termo.uva.es; Domanska, Urszula; Zawadzki, Maciej [Physical Chemistry Division, Faculty of Chemistry, Warsaw University of Technology, 00-664 Warsaw (Poland)

    2008-08-15

    (Solid + liquid) equilibrium temperatures for mixtures containing quinoline and 1-dodecanol, 1-hexadecanol, or 1-octadecanol have been measured using a dynamic method. (Quinoline + benzene, +alkane, or +1-alkanol) systems were investigated using DISQUAC. The corresponding interaction parameters are reported. The model yields a good representation of molar excess Gibbs free energies, G{sup E}, molar excess enthalpies, H{sup E}, and of the (solid + liquid) equilibria, SLE. Interactional and structural effects were analysed comparing H{sup E} and the molar excess internal energy at constant volume, U{sub V}{sup E}. It was encountered that structural effects are very important in systems involving alkanes or 1-alkanols. Interactions between amine molecules are stronger in mixtures with quinoline than in those containing pyridine, which was ascribed to the higher polarizability of quinoline.

  5. [Urothelial carcinoma related to exposure to aromatic amines].

    Science.gov (United States)

    Naito, S; Kumazawa, J

    1989-12-01

    Clinical and statistical observations were made on a group of 438 persons who had worked with aromatic amines (benzidine, 2-naphthylamine, 1-naphthylamine and dianisidine) with reference to their carcinogenic properties in the urinary tract. Urinary tract tumors developed in 68 (15.5%), with an average latent period of 22 years and 11 months. In these 68 cases, upper urinary tract tumors were found in 16 cases, 8 of which had bilateral lesions. The average age of onset was 48.1 ranging from 24 to 79. The incidence of tumors increased with the length of exposure to the amines. There was no finding that smoking habit increased the incidence of tumors in this group. Of the 49 new patients with bladder tumor, urine cytology was positive in 24 (49.0%) and suspicious of malignancy in 10 (20.4%), respectively. This indicated that it could be a useful screening test. Transurethral surgery was most frequently performed as an initial treatment. Recurrence occurred in 50 cases (73.5%), but 5-, 10- and 20-year-survival rates were 89.0 79.3 and 64.7%, respectively, showing a good prognosis. Malignant tumors in other organs developed in 18 (4.1%) of the 438 workers. The incidence of such malignant tumors was significantly higher in the workers who had been exposed to 2-naphthylamine than in others. Our data indicate that close observation is still necessary for early detection of patient with new or recurrent urothelial carcinoma in this group. PMID:2618901

  6. Measurement of nitrosamine and nitramine formation from NOx reactions with amines during amine-based carbon dioxide capture for postcombustion carbon sequestration.

    Science.gov (United States)

    Dai, Ning; Shah, Amisha D; Hu, Lanhua; Plewa, Michael J; McKague, Bruce; Mitch, William A

    2012-09-01

    With years of full-scale experience for precombustion CO(2) capture, amine-based technologies are emerging as the prime contender for postcombustion CO(2) capture. However, concerns for postcombustion applications have focused on the possible contamination of air or drinking water supplies downwind by potentially carcinogenic N-nitrosamines and N-nitramines released following their formation by NO(x) reactions with amines within the capture unit. Analytical methods for N-nitrosamines in drinking waters were adapted to measure specific N-nitrosamines and N-nitramines and total N-nitrosamines in solvent and washwater samples. The high levels of amines, aldehydes, and nitrite in these samples presented a risk for the artifactual formation of N-nitrosamines during sample storage or analysis. Application of a 30-fold molar excess of sulfamic acid to nitrite at pH 2 destroyed nitrite with no significant risk of artifactual nitrosation of amines. Analysis of aqueous morpholine solutions purged with different gas-phase NO and NO(2) concentrations indicated that N-nitrosamine formation generally exceeds N-nitramine formation. The total N-nitrosamine formation rate was at least an order of magnitude higher for the secondary amine piperazine (PZ) than for the primary amines 2-amino-2-methyl-1-propanol (AMP) and monoethanolamine (MEA) and the tertiary amine methyldiethanolamine (MDEA). Analysis of pilot washwater samples indicated a 59 μM total N-nitrosamine concentration for a system operated with a 25% AMP/15% PZ solvent, but only 0.73 μM for a 35% MEA solvent. Unfortunately, a greater fraction of the total N-nitrosamine signal was uncharacterized for the MEA-associated washwater. At a 0.73 μM total N-nitrosamine concentration, a ~25000-fold reduction in concentration is needed between washwater units and downwind drinking water supplies to meet proposed permit limits. PMID:22831707

  7. Blending Behavior of Polysulfone, Polyvinyl Acetate and Amines in Dimethyl Acetamide Solvent

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-02-01

    Full Text Available In this study, research will be carried out to classify the blending behavior of glassy and rubbery polymer in solvent with amines. Commercially preface of a polymer prepared from a new monomer is uncertain and enormously expensive. A strategy to introduce new products into the market without a large investment is to take dissimilar polymers, amines and blend them together to make a new product with unique properties. The blending of polyvinyl acetate, polysulfone and diethanol amine, methyl diethanol amine, mono ethanol amine are examined with dimethyl acetamide solvent, which gives the results of appearance, pH and viscosity values by using measuring device viscometer and general pH testing technique. Through getting these results, the intrinsic miscibility of the mixture was finally established which shows that the homogenous or heterogeneous blends are depending on the blend preparation method and percentage of polymers and amines. The achievement of this advance has been restricted, because the mechanical properties of the blend with amines are classically worse than a simple mixing law would predict.

  8. Basic biogenic aerosol precursors: Agricultural source attribution of volatile amines revised

    Science.gov (United States)

    Kuhn, U.; Sintermann, J.; Spirig, C.; Jocher, M.; Ammann, C.; Neftel, A.

    2011-08-01

    Despite recent evidence on an important role of volatile amines in the nucleation of particulate matter, very scarce information is available on their atmospheric abundance and source distribution. Previous measurements in animal housings had identified livestock husbandry as the main amine source, with trimethylamine (TMA) being the key component. This has led to the assumption that the agricultural sources for amines are similar as for ammonia, emitted throughout the cascade of animal excretion, storage and application in the field. In this study, we present the first micrometeorological flux measurements as well as dynamic enclosure experiments showing that the amine source strength from stored slurry is negligible, implying significant consequences for the global amine emission inventory. In the case of cattle, amine production is attributed to the animal's rumination activity and exhalation is suggested to be an important emission pathway, similar to the greenhouse gas methane. Fodder like hay and silage also emits volatile amines, potentially assigning these alkaloid compounds a key function in enhancing particle formation in remote areas.

  9. Visible Light Induced Green Transformation of Primary Amines to Imines Using a Silicate Supported Anatase Photocatalyst

    Directory of Open Access Journals (Sweden)

    Sifani Zavahir

    2015-01-01

    Full Text Available Catalytic oxidation of amine to imine is of intense present interest since imines are important intermediates for the synthesis of fine chemicals, pharmaceuticals, and agricultural chemicals. However, considerable efforts have been made to develop efficient methods for the oxidation of secondary amines to imines, while little attention has until recently been given to the oxidation of primary amines, presumably owing to the high reactivity of generated imines of primary amines that are easily dehydrogenated to nitriles. Herein, we report the oxidative coupling of a series of primary benzylic amines into corresponding imines with dioxygen as the benign oxidant over composite catalysts of TiO2 (anatase-silicate under visible light irradiation of λ > 460 nm. Visible light response of this system is believed to be as a result of high population of defects and contacts between silicate and anatase crystals in the composite and the strong interaction between benzylic amine and the catalyst. It is found that tuning the intensity and wavelength of the light irradiation and the reaction temperature can remarkably enhance the reaction activity. Water can also act as a green medium for the reaction with an excellent selectivity. This report contributes to the use of readily synthesized, environmentally benign, TiO2 based composite photocatalyst and solar energy to realize the transformation of primary amines to imine compounds.

  10. Deposition of stable amine coating onto polycaprolactone nanofibers by low pressure cyclopropylamine plasma polymerization

    International Nuclear Information System (INIS)

    Amine-rich films are of high interest for the bio-applications including drug delivery and tissue engineering thanks to their high reactivity allowing the formation of the covalent linkages between biomolecules and a surface. However, the bio-applications of amine-rich films require their good stability in water which is often achieved at large expenses of the amine concentration. Recently, non-toxic cyclopropylamine (CPA) has been applied for the plasma polymerization of films bearing high NHx environment combined with the moderate thickness loss (20%) after water immersion for 48 h. In this work, the amine-rich film with the NHx concentration over 7 at.% was deposited on Si substrates and polycaprolactone nanofiber meshes by using CPA plasma polymerization (pulsed mode) in a vertically oriented stainless steel reactor. The substrates were placed at the radio frequency electrode and the ion bombardment caused by direct-current self-bias was suppressed by using high pressure of 50 Pa. Analysis of samples by scanning electron microscopy did not reveal any cracks in the deposited layer formed during a sample immersion in water. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed a slight oxidation of amine groups in water but the film still contained 5 at.% of NHx (according to the N1s XPS fitting) after the immersion. The rapid oxidation of amine groups was observed during the aging experiment carried out in air at room temperature because FTIR revealed an increase of amide peaks that increased progressively with aging time. However, this oxidation was significantly reduced if the plasma polymer was stored at − 20 °C. Since the films exhibit high amine concentration and very good water stability they have great potential for applications as biocompatible functional coatings. - Highlights: • Cyclopropylamine plasma polymers deposited on polycaprolactone nanofibers • Amine-rich films with high water stability

  11. Selective Monoarylation of Primary Amines Using the Pd-PEPPSI-IPent(Cl) Precatalyst.

    Science.gov (United States)

    Sharif, Sepideh; Rucker, Richard P; Chandrasoma, Nalin; Mitchell, David; Rodriguez, Michael J; Froese, Robert D J; Organ, Michael G

    2015-08-10

    A single set of reaction conditions for the palladium-catalyzed amination of a wide variety of (hetero)aryl halides using primary alkyl amines has been developed. By combining the exceptionally high reactivity of the Pd-PEPPSI-IPent(Cl) catalyst (PEPPSI=pyridine enhanced precatalyst preparation, stabilization, and initiation) with the soluble and nonaggressive sodium salt of BHT (BHT=2,6-di-tert-butyl-hydroxytoluene), both six- and five-membered (hetero)aryl halides undergo efficient and selective amination. PMID:26097000

  12. Photoalignment efficiency enhancement of polyimide alignment layers by alkyl-amine vapor treatment

    Science.gov (United States)

    Sakamoto, Kenji; Usami, Kiyoaki; Miki, Kazushi

    2014-08-01

    We have succeeded in enhancing the photoalignment efficiency of polyimide containing azobenzene in the backbone structure by exposing the corresponding precursor (polyamic acid: Azo-PAA) film to alkyl-amine vapor prior to photoalignment. The Azo-PAA film absorbed alky-amines and swelled by 300%. The photoinduced rotation of the Azo-PAA backbone structure occurred more easily in the swollen film. Most of the alkyl-amines in the swollen film desorbed during thermal imidization. As a result of the photoalignment efficiency enhancement, we also succeeded in expanding the controllable pretilt angle range of liquid crystals up to 38° without the appearance of threadlike disclination loops.

  13. Study of the structure of H2SO4-amine Primene 81R and Fe(III)-amine Primene 81R sulphate compounds by infrared spectroscopy

    International Nuclear Information System (INIS)

    The primary amine Primene 81R extracts sulphuric acid from aqueous solutions to form the corresponding sulphate and bisulphate salts. The infrared study shows that in the sulphate salt, the sulphate group presents a Td symmetry, whereas the amine bisulphate presents a C3v symmetry for the bisulphate group. The former of the above compounds, the amine sulphate, is complexed to Fe(III) in sulphate media, and two complexes are extracted depending on temperature. At 8 degree centigree or lower temperatures a complex with the stoichiometric formula 4(RNH3)2 SO4 (Fe(OH)SO4)2 is formed, whereas at 50 degree centigree or higher temperatures the complex with the stoichiometric formula 3(RNH3)2 SO4 (Fe(OH)SO4)2 is formed. The infrared spectrum of both complexes is very similar and it is consistent with a weaker interaction between the protons associated with the amine group and the anion, and with a change in the symmetry of the sulphate group respect to the symmetry presented in the amine sulphate salt. (Author) 18 refs

  14. Grafting of Amines on Ethanol-Extracted SBA-15 for CO2 Adsorption

    Directory of Open Access Journals (Sweden)

    Yuhan Sun

    2013-03-01

    Full Text Available SBA-15 prepared via ethanol extraction for template removing was grafted with three kinds of amine precursors (mono-, di-, tri-aminosilanes to synthesis new CO2 adsorbents. The SBA-15 support and the obtained adsorbents were characterized by X-ray diffraction (XRD, small-angle X-ray scattering (SAXS, N2 adsorption/desorption, thermogravimetry (TG, elemental analysis, Fourier transform infrared (FTIR spectrometry, scanning electron microscopy (SEM and transmission electron microscopy (TEM. It was found that, except higher silanol density, the ethanol-extracted SBA-15 support possessed a more regular mesophase and thicker walls than traditionally calcined samples, leading to a good stability of the adsorbent under steam treatment. The adsorption capacity of different amine-grafted samples was found to be influenced by not only the surface amine density, but also their physiochemical properties. These observations provide important support for further studies of applying amine-grafted adsorbents in practical CO2 capture process.

  15. A Selection of Amine Sorbents for CO2 Capture from Flue Gases

    Directory of Open Access Journals (Sweden)

    Wilk Andrzej

    2015-03-01

    Full Text Available Amine absorption processes are widely used in the industry to purify refinery gases, process gases or natural gas. Recently, amine absorption has also been considered for CO2 removal from flue gases. It has a number of advantages, but there is one major disadvantage - high energy consumption. This can be reduced by using an appropriate sorbent. From a group of several dozen solutions, three amine sorbents were selected based on primary, tertiary and sterically hindered amines. The solutions were used to test CO2 absorption capacity, absorption kinetics and heat of CO2 absorption. Additional tests were performed on the actual absorber-desorber system to indicate the most appropriate sorbent for capturing CO2 from flue gases.

  16. Nucleophilic addition-triggered lanthanide luminescence allows detection of amines by Eu(thenoyltrifluoroacetone)3.

    Science.gov (United States)

    Zhou, Zhan; Wang, Qianming; Lin, Jintai; Chen, Yanna; Yang, Chuqin

    2012-01-01

    Herein, a novel fluorescent indicator for the real-time monitoring of amines is described. This probe contains a complex of europium-(thenoyltrifluoroacetone)(3) (Eu(TTA)(3)) that efficiently reacts with primary and secondary amines. The electron-withdrawing trifluoroacetyl undergoes a nucleophilic addition with amines, and the complex was used to selectively detect BuNH(2) and Et(2) NH (quenching concentration for BuNH(2): 10(-4) M, for Et(2)NH: 1.2 × 10(-3) M) by monitoring emission; no changes were observed in the emission spectrum of Eu(TTA)(3) in the presence of Et(3)N, [Bu(4)N]Cl, or PhNH(2) in aqueous solution (THF/H(2)O = 1:1). The ratio of emission intensity to amine concentration was linear by the least-squares fitting method. PMID:22458513

  17. Structure-Function Study of Tertiary Amines as Switchable Polarity Solvents

    Energy Technology Data Exchange (ETDEWEB)

    Aaron D. Wilson; Frederick F. Stewart

    2014-02-01

    A series of tertiary amines have been screened for their function as switchable polarity solvents (SPS). The relative ratios of tertiary amine and carbonate species as well as maximum possible concentration were determined through quantitative 1H and 13C NMR spectroscopy. The viscosities of the polar SPS solutions were measured and ranged from near water in dilute systems through to gel formation at high concentrations. The van't Hoff indices for SPS solutions were measured through freezing point depression studies as a proxy for osmotic pressures. A new form of SPS with an amine : carbonate ratio significantly greater than unity has been identified. Tertiary amines that function as SPS at ambient pressures appear to be limited to molecules with fewer than 12 carbons. The N,N-dimethyl-n-alkylamine structure has been identified as important to the function of an SPS.

  18. Analysis of amines by pH-Metrie in organic media

    International Nuclear Information System (INIS)

    Amines with long hydro carbonic strength and principally Trioclkylamines, are characterised by an important complexation mechanism for certain metals. This is the case for trioctylamine (TOA) which is very used in purification and uranium recovery from certain ores (1,2). This substance is generally found mixed with mono and di-octyl amines in commercial products and in synthesis mixtures. The purpose of this work is to develop a pH titration method in an organic media for a mixture consisted of mono, di and tri octyl amines (MOA, DOA et TOA). Adequate operating analysis condition have been proposed, based on intrinsic chemical properties for each precipitated substances (3,4). The obtained results show that this technique is recommended for qualitative and quantitative analysis of precipitated amines mixtures. The method is reproducible and the detection limit can reach 0,0001 molar

  19. Flotation behavior of four dodecyl tertiary amines as collectors of diaspore and kaolinite

    Institute of Scientific and Technical Information of China (English)

    Changmiao Liu; Feng Ansheng; GUO Zhenxu; Cao Xuefeng; Hu Yuehua

    2011-01-01

    The flotation of diaspore and kaolinite by one of a series of tertiary amines (DRN, DEN, DPN and DBN) was investigated. The tertiary amines show better floating recovery for kaolinite compared to diaspore. The maximum recovery D-value is 45% over a pH range from 3 to 8. FT-IR spectra confirm the presence of hydroxyl groups on the surface of kaolinite and diaspore. Zeta potential measurements show that the mineral surfaces are negatively charged over a wide pH range. Ionization of hydroxyl groups mainly accounts for the surface charging mechanism. The adsorption of tertiary amines onto the mineral surface is due mainly to electrostatic effects and the difference in electrostatic effect between a collector and the two minerals can explain the flotation separation. Inductive electronic and steric effects from the substituent groups result in different collecting powers for the four tertiary amines.

  20. Synthesis of Derivatives of Biogenic Amines Labelled with Radioactive Tracers for Brain Imaging

    OpenAIRE

    Arturo A. Vitale

    2000-01-01

    Endogenous derivatives of biogenic amines, such as phenethylamines, indolalkylamines and harmines, have been extensively studied as usual constituents of body fluids. Methylated derivatives of indolalkylamines have been also related to mental disorders, e.g. schizophrenia and hallucination.

  1. Amine effect on lanthanum and scandium extraction with caproic and α-bromocaproic acids

    International Nuclear Information System (INIS)

    Lanthanum and scandium extraction with 1 mol. chloroform solutions of n-caproic and α-bromocaproic acids in the presence of benzyl amine and n-butyl-amine, pyridine and 2-aminopyridine is investigated. Composition of carboxylates in organic phase is determined. It is established that introduction of strong organic nitrogen-containing bases-n-butylamine, benzyl amine-extends considerably pH range at which the mentioned metals are extracted into chloroform quantitatively. The effect of citrate- and tartrate- ions upon the extraction of capronates and aminocapronates of scandium and lanthanum is investigated. To separate lanthanum and scandium from interfering elements investigated is extraction of magnesium, calcium, strontium and barium by the mixtures of the above carboxylic acids and amines. Developed are methods of extraction separation of scandium and lanthanum from alkaline-earth elements taking solutions of artificial mixtures as examples

  2. Purification of wet process phosphoric acid by solvent extraction with long-chain aliphatic amines

    International Nuclear Information System (INIS)

    Purification of phosphoric acid by solvent extraction with long-chain aliphatic amines is investigated. Extraction of cadmium is extensively examined regarding the importance of the aqueous phase, the diluent and the amine. The solubility of tri-n-octyl-amine is determined in water and phosphoric acid solutions. Properties of valuable constituent such as uranium and yttrium are screened. Modelling of the system is performed by adapting Bromley's model for electrolytes to the different dissociation/association equilibria in the aqueous phase. In the organic phase simple expressions are used for the non-ideal behaviour. Amine-acid equilibria are investigated for all acids present in industrial phosphoric acid. New extraction constants are calculated for phosphoric and hydro- fluosilic acid. Calculations are compared with experiments both from binary and multicomponent acid mixtures

  3. Amination of ω-Functionalized Aliphatic Primary Alcohols by a Biocatalytic Oxidation–Transamination Cascade

    Science.gov (United States)

    Pickl, Mathias; Fuchs, Michael; Glueck, Silvia M; Faber, Kurt

    2015-01-01

    Amination of non-activated aliphatic fatty alcohols to the corresponding primary amines was achieved through a five-enzyme cascade reaction by coupling a long-chain alcohol oxidase from Aspergillus fumigatus (LCAO_Af) with a ω-transaminase from Chromobacterium violaceum (ω-TA_Cv). The alcohol was oxidized at the expense of molecular oxygen to yield the corresponding aldehyde, which was subsequently aminated by the PLP-dependent ω-TA to yield the final primary amine product. The overall cascade was optimized with respect to pH, O2 pressure, substrate concentration, decomposition of H2O2 (derived from alcohol oxidation), NADH regeneration, and biocatalyst ratio. The substrate scope of this concept was investigated under optimized conditions by using terminally functionalized C4–C11 fatty primary alcohols bearing halogen, alkyne, amino, hydroxy, thiol, and nitrile groups. PMID:26583050

  4. The thermal desorption of CO2 from amine carbamate solutions for the 13C isotope enrichment

    Science.gov (United States)

    Dronca, S.; Varodi, C.; Gligan, M.; Stoia, V.; Baldea, A.; Hodor, I.

    2012-02-01

    The CO2 desorption from amine carbamate in non-aqueous solvents is of major importance for isotopic enrichment of 13C. A series of experiments were carried out in order to set up the conditions for the CO2 desorption. For this purpose, a laboratory- scale plant for 13C isotope separation by chemical exchange between CO2 and amine carbamate was designed and used. The decomposition of the carbamate solution was mostly produced in the desorber and completed in the boiler. Two different-length desorbers were used, at different temperatures and liquid flow rates of the amine-non-aqueous solvent solutions. The residual CO2 was determined by using volumetric and gaschromatographic methods. These results can be used for enrichment of 13C by chemical exchange between CO2 and amine carbamate in nonaqueous solvents.

  5. Validation of an HPLC Analytical Method for Determination of Biogenic Amines in Agricultural Products and Monitoring of Biogenic Amines in Korean Fermented Agricultural Products.

    Science.gov (United States)

    Yoon, Hyeock; Park, Jung Hyuck; Choi, Ari; Hwang, Han-Joon; Mah, Jae-Hyung

    2015-09-01

    An HPLC analytical method was validated for the quantitative determination of biogenic amines in agricultural products. Four agricultural foods, including apple juice, Juk, corn oil and peanut butter, were selected as food matrices based on their water and fat contents (i.e., non-fatty liquid, non-fatty solid, fatty liquid and fatty solid, respectively). The precision, accuracy, recovery, limit of detection (LOD) and quantification (LOQ) were determined to test the validity of an HPLC procedure for the determination of biogenic amines, including tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine, in each matrix. The LODs and LOQs for the biogenic amines were within the range of 0.01~0.10 mg/kg and 0.02~0.31 mg/kg, respectively. The relative standard deviation (RSD) of intraday for biogenic amine concentrations ranged from 1.86 to 5.95%, whereas the RSD of interday ranged from 2.08 to 5.96%. Of the matrices spiked with biogenic amines, corn oil with tyramine and Juk with putrescine exhibited the least accuracy of 84.85% and recovery rate of 89.63%, respectively, at the lowest concentration (10 mg/kg). Therefore, the validation results fulfilled AOAC criteria and recommendations. Subsequently, the method was applied to the analysis of biogenic amines in fermented agricultural products for a total dietary survey in Korea. Although the results revealed that Korean traditional soy sauce and Doenjang contained relatively high levels of histamine, the amounts are of no concern if these fermented agricultural products serve as condiments. PMID:26483889

  6. A Colorimetric Sensor for Qualitative Discrimination and Quantitative Detection of Volatile Amines

    OpenAIRE

    Zhonglin Tang; Jianhua Yang; Junyun Yu; Bo Cui

    2010-01-01

    We have developed a novel colorimetric sensor based on a digital camera and white LED illumination. Colorimetric sensor arrays (CSAs) were made from a set of six chemically responsive dyes impregnated on an inert substrate plate by solution casting. Six common amine aqueous solutions, including dimethylamine, triethylamine, diisopropyl-amine, aniline, cyclohexylamine, and pyridine vaporized at 25 °C and six health-related trimethylamine (TMA) concentrations including 170 ppm, 51 ppm, 8 ppm, 2...

  7. Investigation on Nonwovens Leukocyte Filtering Materials Treated with Amine and Alkali Solution

    Institute of Scientific and Technical Information of China (English)

    SUN Zhi-liang; CHI Ting; KE Qin-fei

    2002-01-01

    Filtering materials are chosen according to the mechanism of blood filtration and mathematics model,then the material is treated with amine and alkail solution. There is cooperation and synergism between alkaliand amine, and the actions are realized in three stages. After modification the material treated has accessibilitygroups-NH2, and slits appeared in the surface of fiber, so the wettability of materials is improved distinctly; the diameter and aperture of fiber have no changes basically.

  8. Amine-Linked Single Molecule Circuits: Systematic Trends Across Molecular Families

    OpenAIRE

    Hybertsen, Mark S.; Venkataraman, Latha; Klare, Jennifer E.; Whalley, Adam C.; Steigerwald, Michael L.; Nuckolls, Colin

    2008-01-01

    A comprehensive review is presented of single molecule junction conductance measurements across families of molecules measured while breaking a gold point contact in a solution of molecules with amine end groups. A theoretical framework unifies the picture for the amine-gold link bonding and the tunnel coupling through the junction using Density Functional Theory based calculations. The reproducible electrical characteristics and utility for many molecules is shown to result from the selectiv...

  9. Interface Effects on Tunneling Magnetoresistance in Organic Spintronics with Flexible Amine-Au Links

    OpenAIRE

    Gorjizadeh, Narjes; Quek, Su Ying

    2013-01-01

    Organic spintronics is a promising emerging field, but the sign of the tunneling magnetoresistance (TMR) is highly sensitive to interface effects, a crucial hindrance to applications. A key breakthrough in molecular electronics was the discovery of amine-Au link groups that give reproducible conductance. Using first principles calculations, we predict that amine-Au links give improved reproducibility in organic spintronics junctions with Au-covered Fe leads. The Au layers allow only states wi...

  10. Method for Preparation of Amides from Alcohols and Amines by Extrusion of Hydrogen

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a method for preparation of carboxamides using alcohols and amines as starting materials in a dehydrogenative coupling reaction catalyzed by a ruthenium N-heterocyciic carbene (NHC) complex, which may be prepared in situ.......The present invention relates to a method for preparation of carboxamides using alcohols and amines as starting materials in a dehydrogenative coupling reaction catalyzed by a ruthenium N-heterocyciic carbene (NHC) complex, which may be prepared in situ....

  11. Uncertainties in assessing the environmental impact of amine emissions from a CO2 capture plant

    OpenAIRE

    Karl, Matthias; Castell, Nuria; Simpson, David; Solberg, Sverre; Starrfelt, Jostein; Svendby, Tove Marit; Walker, Sam-Erik; Wright, Richard Frederic

    2014-01-01

    In this study, a new model framework that couples the atmospheric chemistry transport model system WRF-EMEP and the multimedia fugacity level III model was used to assess the environmental impact of amine emissions to air from post-combustion carbon dioxide capture. The modelling framework was applied to a typical carbon capture plant artificially placed at Mongstad, west coast of Norway. WRF-EMEP enables a detailed treatment of amine chemistry in addition to atmospheric transport and depo...

  12. β-Elimination of an Aziridine to an Allylic Amine: A Mechanistic Study

    OpenAIRE

    Morgan, Kathleen M.; Brown, Garry; Pichon, Monique A.; Green, Geannette Y.

    2011-01-01

    The base-induced rearrangement of aziridines has been examined using a combination of calculations and experiment. The calculations show that the substituent on nitrogen is a critical feature that greatly affects the favorability of both α-deprotonation, and β-elimination to form an allylic amine. Experiments were carried out to determine whether E2-like rearrangement to the allylic amine with lithium diisopropyl amide (LDA) is possible. N-Tosyl aziridines were found to deprotonate on the tos...

  13. Use of plastic-based analytical device, smartphone and chemometric tools to discriminate amines

    OpenAIRE

    Reddy, SM; Bueno, L.; Meloni, G; Paixao, TRLC

    2015-01-01

    Amine-based volatile compounds released bymicroorganisms offer an alternative diagnostic approach for the identification of foodborne pathogens. Our objective has been to solvent cast cellulose acetate membranes to immobilise dyes and to use the resultant membranes as a plastic device to discriminate between different types of amines (triethylamine, isobutylamine, isopentylamine). The plastic device consisted of an array of membranes with five pH indicators (namely alizarin, bromophenol blue,...

  14. A novel squaraine dye with squaramide as a scaffold and the colorimetric detection of amine

    Institute of Scientific and Technical Information of China (English)

    Chuan Guo Sun; Qian Lin; Nan Yan Fu

    2012-01-01

    A novel unsymmetrical squaramide-linked squaraine dye (SQ) has been synthesized through squaramide 3 and semisquaraine 6.The molecular structure of SQ has been characterized by 1H NMR,IR and MS.Due to the influence of the hydrogen bond and the solvent effect,SQ exhibits unique spectral properties compared with typical squaraine dyes.For its excellent ability of binding primary amine,SQ is a promising receptor of recognizing primary amine.

  15. Synthesis of periodic mesoporous organosilicas functionalized with different amine-organoalkoxysilanes via direct co-condensation

    Energy Technology Data Exchange (ETDEWEB)

    Suriyanon, Nakorn [International Postgraduate Programs in Environmental Management, Graduate School, Chulalongkorn University, Pathumwan, Bangkok 10330 (Thailand); Center of Excellence for Environmental and Hazardous Waste Management (EHWM), Pathumwan, Bangkok 10330 (Thailand); Punyapalakul, Patiparn [Center of Excellence for Environmental and Hazardous Waste Management (EHWM), Pathumwan, Bangkok 10330 (Thailand); Department of Environmental Engineering, Faculty of Engineering, Chulalongkorn University, Pathumwan, Bangkok 10330 (Thailand); Ngamcharussrivichai, Chawalit, E-mail: Chawalit.Ng@Chula.ac.th [Fuels Research Center, Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330 (Thailand); Center of Excellence on Petrochemical and Materials Technology (PETROMAT), Chulalongkorn University, Pathumwan, Bangkok 10330 (Thailand)

    2015-01-15

    A series of amine-functionalized periodic mesoporous organosilicas (PMOs) were synthesized from bis(triethoxysilyl)ethane via surfactant-templating using supramolecular assemblies of hexadecyltrimethylammonium chloride under basic conditions. Functionalization of the PMO materials was performed via direct co-condensation in the presence of mono-, di- or tri-amine-organoalkoxysilanes. The effect of the type and concentration of the added organosilanes on the physicochemical properties of the functionalized PMOs were investigated. Thermogravimetric/differential thermal analysis (TG/DTA) and Fourier transform infrared spectroscopy (FTIR) confirmed the presence of the inorganic–organic hybrid framework functionalized with the amine groups. The total nitrogen content of the functionalized PMOs ranged from 0.26 to 1.27 mmol/g. The materials possessed a hexagonal lattice with the highly ordered mesostructure being preserved after the amine-functionalization as evidenced by X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM). The N{sub 2} adsorption–desorption measurement revealed that the materials had high specific surface areas (963–1252 m{sup 2}/g) and a relatively high total pore volume (0.52–0.85 cm{sup 3}/g). The mesopore size and wall thickness of these materials varied in relation with the molecular size and the loading of the organosilanes. Moreover, the morphology of the PMO materials was increasingly transformed from irregular shaped particles to spheres with increasing amounts of amine-functional groups or with organo-functional groups with several amine units. - Highlights: • Periodic mesoporous organosilicas (PMOs) were functionalized via co-condensation. • Long-chain organosilane with three amine units was employed a precursor. • Hexagonal mesostructure of PMO was preserved at a 40 mol% loading level. • Amine-functionalized PMOs had a high surface area and total pore volume. • Their morphology depended on the

  16. Cocaine affects foraging behaviour and biogenic amine modulated behavioural reflexes in honey bees

    OpenAIRE

    Eirik Søvik; Naïla Even; Radford, Catherine W.; Barron, Andrew B.

    2014-01-01

    In humans and other mammals, drugs of abuse alter the function of biogenic amine pathways in the brain leading to the subjective experience of reward and euphoria. Biogenic amine pathways are involved in reward processing across diverse animal phyla, however whether cocaine acts on these neurochemical pathways to cause similar rewarding behavioural effects in animal phyla other than mammals is unclear. Previously, it has been shown that bees are more likely to dance (a signal of perceived rew...

  17. STRUCTURE CHARACTERIZATION AND APPLICATION OF NI HYDROTALCITE AS ENVIRONMENTALLY FRIENDLY CATALYSTS FOR REDUCTIVE AMINATION OF BENZALDEHYDE

    OpenAIRE

    Ateeq Rahman

    2013-01-01

    Ni/hydrotalcite catalysts with ratios 2:1, 2.5 and 3:1 exhibit catalytic activity for reductive amination of benzaldehyde to amine. Ni HTLC is prepared by co-precipitation method, which is characterized by XRD, IR and TPR instruments. Carbonate present in the brucite layer of hydrotalcite and calcined hydrotalcite produce mixed oxides, exhibits catalytic activity for variety of organic transformations ex: selective aldol, nitro aldol, wittig, knoevenegal oxidation, reduction reactions. Hydrot...

  18. Administration of biogenic amines to Saanen kids: effects on growth performance and meat quality

    OpenAIRE

    E. Fusi; R. Rebucci; C. Pecorini; Rossi, L.; F. Cheli

    2011-01-01

    Biogenic amines are low molecular weight organic bases present in all organisms. The most common are putrescine, cadaverine, spermine, spermidine, histamine, tryptamine and β- phenylethylamine. In low concentrations they are essential for the normal growth and differentiation of cells (Bardócz et al., 1995), but in larger quantities are harmful to humans and livestock. Biogenic amines are naturally present in silage; however their presence in high concentrations may be a sign of u...

  19. Managing your wine fermentation to reduce the risk of biogenic amine formation

    OpenAIRE

    MaretDu Toit

    2012-01-01

    Biogenic amines are nitrogenous organic compounds produced in wine from amino acid precursors mainly by microbial decarboxylation. The concentration of biogenic amines that can potentially be produced is dependent on the amount of amino acid precursors in the medium, the presence of decarboxylase positive microorganisms and conditions that enable microbial or biochemical activity such as the addition of nutrients to support the alcoholic and malolactic fermentation (MLF) inoculated starter cu...

  20. A Review: Microbiological, Physicochemical and Health Impact of High Level of Biogenic Amines in Fish Sauce

    OpenAIRE

    Muhammad Z. Zaman; A. S. Abdulamir; Fatimah A. Bakar; Jinap Selamat; Jamilah Bakar

    2009-01-01

    Problem statement: Biogenic amines are basic nitrogenous compounds present in a wide variety of foods and beverages. Their formations were mainly due to the amino acids decarboxylase activity of certain microorganisms. Excessive intake of biogenic amines could induce many undesirable physiological effects determined by their psychoactive and vasoactive action. Fish sauce which is considered as a good source of dietary protein, amino acids, vitamins and minerals was a popular condiment in Sout...

  1. Changes of the content of biogenic amines during winemaking of Sauvignon wines

    OpenAIRE

    Kovačević Ganić, Karin; Gracin, L.; Komes, Draženka; Ćurko, Natka; Lovrić, T.

    2009-01-01

    The aim of the present work was to study the changes of the content of biogenic amines during winemaking and maturation processes of wines made from Vitis vinifera cv Sauvignon grapes from Slavonia region (vintage 2008). Biogenic amines were quantified using a reversed-phase high performance liquid chromatography (HPLC) with fluorescence detection after pre-column derivatization with o-phthalaldehyde (OPA). Samples used in this study were obtained during production of Sauvignon wines in three...

  2. Control of Biogenic Amines in Food—Existing and Emerging Approaches

    OpenAIRE

    Naila, Aishath; Flint, Steve; Fletcher, Graham; Bremer, Phil; Meerdink, Gerrit

    2010-01-01

    Biogenic amines have been reported in a variety of foods, such as fish, meat, cheese, vegetables, and wines. They are described as low molecular weight organic bases with aliphatic, aromatic, and heterocyclic structures. The most common biogenic amines found in foods are histamine, tyramine, cadaverine, 2-phenylethylamine, spermine, spermidine, putrescine, tryptamine, and agmatine. In addition octopamine and dopamine have been found in meat and meat products and fish. The formation of biogeni...

  3. Managing Your Wine Fermentation to Reduce the Risk of Biogenic Amine Formation

    OpenAIRE

    Smit, Anita Yolandi; Engelbrecht, Lynn; du Toit, Maret

    2012-01-01

    Biogenic amines are nitrogenous organic compounds produced in wine from amino acid precursors mainly by microbial decarboxylation. The concentration of biogenic amines that can potentially be produced is dependent on the amount of amino acid precursors in the medium, the presence of decarboxylase positive microorganisms and conditions that enable microbial or biochemical activity such as the addition of nutrients to support the inoculated starter cultures for alcoholic and malolactic fermenta...

  4. Metabolism of biogenic amines in acute cerebral ischemia: Influence of systemic hyperglycemia

    Directory of Open Access Journals (Sweden)

    Milovanović Aleksandar

    2012-01-01

    Full Text Available Dopamine, norepinephrine and serotonin are biogenic amines which are transmitters of the central nervous system. The effects of ischemia on the brain parenchyma depends on many factors, such is the mechanism of blood flow interruption, velocity of the occurring blood flow interruption, duration of an ischemic episode, organization of anatomical structures of the brain blood vessels etc., which all influence the final outcome. During interruption of the brain circulation in experimental or clinical conditions, neurotransmitter metabolism, primarily of biogenic amines, is disturbed. Many researches with various experimental models of complete ischemia reported a decrease in the content of norepinephrine, dopamine and serotonin in the CNS tissue. It was proven that hyperglycemia can drastically increase cerebral injury followed by short-term cerebral ischemia. Considering the fact that biogenic amines (dopamine, norepinephrine and serotonin influence the size of neurologic damage, as well as the fact that in hyperglycemic conditions infarct size (from the morphological aspect is larger relative to normoglycemic status, the intention was to evaluate the role of biogenic amines in occurrence of damage in conditions of hyperglycemia, i.e. in the case of brain apoplexia in diabetics. Analysis of biogenic amines metabolism in states of acute hyperglycemia, as well as analysis of the effects of reversible and irreversible brain ischemia on metabolism of serotonin, dopamine and norepinephrine, showed that acute hyperglycemia slows down serotonin, dopamine and norepinephrine metabolism in the cerebral cortex and n. caudatus. Brain ischemia in normoglycemic animals by itself has no influence on biogenic amines metabolism, but the effect of ischemia becomes apparent during reperfusion. In recirculation, which corresponds to the occurrences in penumbra, release of biogenic amines is uncontrolled and increased. Brain ischemia in acute hyperglycemic animals

  5. Relationship Between Biogenic Amines and Free Amino Acid Contents of Winesand Musts from Alentejo (Portugal)

    OpenAIRE

    Herbert, Paulo; Cabrita, Maria Joao; Ratola, Nuno; Laureano, Olga; Alves, Arminda

    2006-01-01

    The concentration of biogenic amines and free amino acids was studied in 102 Portuguese wines and 18 musts from Alentejo demarcated (D.O.C.) regions. Most wines were commercial, except for 38 monovarietals obtained by micro vinification. Musts from the varieties used to produce the latter wines were also studied. Both biogenic amines and free amino acids were analyzed by HPLC using fluorescence detection for their o-phthalaldehyde/fluorenylmethyl chloroformate (OPA/FMOC) deriva...

  6. Ligand-gated chloride channels are receptors for biogenic amines in C. elegans

    OpenAIRE

    Ringstad, Niels; Abe, Namiko; Horvitz, H. Robert

    2009-01-01

    Biogenic amines such as serotonin and dopamine are intercellular signaling molecules that function widely as neurotransmitters and neuromodulators. We have identified in the nematode Caenorhabditis elegans three ligand-gated chloride channels that are receptors for biogenic amines: LGC-53 is a high-affinity dopamine receptor, LGC-55 is a high-affinity tyramine receptor, and LGC-40 is a low-affinity serotonin receptor that is also gated by choline and acetylcholine. lgc-55 mutants are defectiv...

  7. Concentration of Biogenic Amines in ‘Pinot Noir’ Wines Produced in Croatia

    OpenAIRE

    Ana Jeromel; Karin Kovačević Ganić; Stanka Herjavec; Marin Mihaljević; Ana Marija Jagatić Korenika; Ivana Rendulić; Marijana Čolić

    2012-01-01

    The origins of biogenic amines are sound grapes, alcoholic fermentations, malolactic fermentation and microbial activities during wine storage. These biologically produced amines are essential at low concentrations for optimal metabolic and physiological functions in animals, plants and micro-organisms. During alcoholic fermentation the degree of maceration is the first factor that affects the extraction of compounds present in the grape skin, among them aminoacids, precursors of bioge...

  8. PCR methods for the detection of biogenic amine-producing bacteria on wine

    OpenAIRE

    Landete, José María; Rivas, Blanca de las; Marcobal, Ángela; Muñoz, Rosario

    2011-01-01

    Biogenic amines are low molecular weight organic bases frequently found in wine. Several toxicological problems resulting from the ingestion of wine containing biogenic amines have been described. In wine, histamine, tyramine, and putrescine are mainly produced by the decarboxylation of the amino acid histidine, tyrosine, and ornithine, respectively, by lactic acid bacteria action. The bacterial ability to decarboxylate amino acids is highly variable, and therefore the...

  9. Synthesis of periodic mesoporous organosilicas functionalized with different amine-organoalkoxysilanes via direct co-condensation

    International Nuclear Information System (INIS)

    A series of amine-functionalized periodic mesoporous organosilicas (PMOs) were synthesized from bis(triethoxysilyl)ethane via surfactant-templating using supramolecular assemblies of hexadecyltrimethylammonium chloride under basic conditions. Functionalization of the PMO materials was performed via direct co-condensation in the presence of mono-, di- or tri-amine-organoalkoxysilanes. The effect of the type and concentration of the added organosilanes on the physicochemical properties of the functionalized PMOs were investigated. Thermogravimetric/differential thermal analysis (TG/DTA) and Fourier transform infrared spectroscopy (FTIR) confirmed the presence of the inorganic–organic hybrid framework functionalized with the amine groups. The total nitrogen content of the functionalized PMOs ranged from 0.26 to 1.27 mmol/g. The materials possessed a hexagonal lattice with the highly ordered mesostructure being preserved after the amine-functionalization as evidenced by X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM). The N2 adsorption–desorption measurement revealed that the materials had high specific surface areas (963–1252 m2/g) and a relatively high total pore volume (0.52–0.85 cm3/g). The mesopore size and wall thickness of these materials varied in relation with the molecular size and the loading of the organosilanes. Moreover, the morphology of the PMO materials was increasingly transformed from irregular shaped particles to spheres with increasing amounts of amine-functional groups or with organo-functional groups with several amine units. - Highlights: • Periodic mesoporous organosilicas (PMOs) were functionalized via co-condensation. • Long-chain organosilane with three amine units was employed a precursor. • Hexagonal mesostructure of PMO was preserved at a 40 mol% loading level. • Amine-functionalized PMOs had a high surface area and total pore volume. • Their morphology depended on the concentration and

  10. A general and facile one-pot process of isothiocyanates from amines under aqueous conditions

    OpenAIRE

    Nan Sun; Bin Li,; Jianping Shao; Weimin Mo; Baoxiang Hu; Zhenlu Shen; Xinquan Hu

    2012-01-01

    A general and facile one-pot protocol for the preparation of a broad range of alkyl and aryl isothiocyanates has been developed from their corresponding primary amines under aqueous conditions. This synthetic process involves an in situ generation of a dithiocarbamate salt from the amine substrate by reacting with CS2 followed by elimination to form the isothiocyanate product with cyanuric acid as the desulfurylation reagent. The choice of solvent is of decisive importance for the successful ...

  11. Seasonal variation of aliphatic amines in marine sub-micrometer particles at the Cape Verde islands

    Directory of Open Access Journals (Sweden)

    C. Müller

    2009-07-01

    Full Text Available Monomethylamine (MA, dimethylamine (DMA and diethylamine (DEA were detected at non-negligible concentrations in sub-micrometer particles at the Cap Verde Atmospheric Observatory (CVAO located on the island of São Vicente in Cape Verde during algal blooms in 2007. The concentrations of these amines in five stage impactor samples ranged from 0 to 30 pg m−3 for MA, 130 to 360 pg m−3 for DMA and 5 to 110 pg m−3 for DEA during the spring bloom in May 2007 and 2 to 520 pg m−3 for MA, 100 to 1400 pg m−3 for DMA, 90 to 760 pg m−3 for DEA during an unexpected winter algal bloom in December 2007. Anomalously high Saharan dust deposition and intensive ocean layer deepening were found at the Atmospheric Observatory and the associated Ocean Observatory during algal bloom periods. The highest amine concentrations in fine particles (impactor stage 2, 0.14–0.42 μm indicates that amines are likely taken up from the gas phase into the acidic sub-micrometer particles. The contribution of amines to the organic carbon (OC content ranged from 0.2 to 2.5%C in the winter months, indicating the importance of this class of compounds to the carbon cycle in the marine environment. Furthermore, aliphatic amines originating from marine biological sources likely contribute significantly to the organic nitrogen in the marine atmosphere. The average contribution of the amines to the total detected nitrogen content in submicron particles can be non-negligible, especially in the winter months (0.1% N to 1.5% N in the sum of nitrate, ammonium and amines. This indicates that these smaller aliphatic amines can be important for the carbon and the nitrogen cycles in the remote marine environment.

  12. New procedure of selected biogenic amines determination in wine samples by HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Piasta, Anna M.; Jastrzębska, Aneta, E-mail: aj@chem.uni.torun.pl; Krzemiński, Marek P.; Muzioł, Tadeusz M.; Szłyk, Edward

    2014-06-27

    Highlights: • We proposed new procedure for derivatization of biogenic amines. • The NMR and XRD analysis confirmed the purity and uniqueness of derivatives. • Concentration of biogenic amines in wine samples were analyzed by RP-HPLC. • Sample contamination and derivatization reactions interferences were minimized. - Abstract: A new procedure for determination of biogenic amines (BA): histamine, phenethylamine, tyramine and tryptamine, based on the derivatization reaction with 2-chloro-1,3-dinitro-5-(trifluoromethyl)-benzene (CNBF), is proposed. The amines derivatives with CNBF were isolated and characterized by X-ray crystallography and {sup 1}H, {sup 13}C, {sup 19}F NMR spectroscopy in solution. The novelty of the procedure is based on the pure and well-characterized products of the amines derivatization reaction. The method was applied for the simultaneous analysis of the above mentioned biogenic amines in wine samples by the reversed phase-high performance liquid chromatography. The procedure revealed correlation coefficients (R{sup 2}) between 0.9997 and 0.9999, and linear range: 0.10–9.00 mg L{sup −1} (histamine); 0.10–9.36 mg L{sup -1} (tyramine); 0.09–8.64 mg L{sup −1} (tryptamine) and 0.10–8.64 mg L{sup −1} (phenethylamine), whereas accuracy was 97%–102% (recovery test). Detection limit of biogenic amines in wine samples was 0.02–0.03 mg L{sup −1}, whereas quantification limit ranged 0.05–0.10 mg L{sup −1}. The variation coefficients for the analyzed amines ranged between 0.49% and 3.92%. Obtained BA derivatives enhanced separation the analytes on chromatograms due to the inhibition of hydrolysis reaction and the reduction of by-products formation.

  13. Preparation of aminated chitosan/alginate scaffold containing halloysite nanotubes with improved cell attachment.

    Science.gov (United States)

    Amir Afshar, Hamideh; Ghaee, Azadeh

    2016-10-20

    The chemical nature of biomaterials play important role in cell attachment, proliferation and migration in tissue engineering. Chitosan and alginate are biodegradable and biocompatible polymers used as scaffolds for various medical and clinical applications. Amine groups of chitosan scaffolds play an important role in cell attachment and water adsorption but also associate with alginate carboxyl groups via electrostatic interactions and hydrogen bonding, consequently the activity of amine groups in the scaffold decreases. In this study, chitosan/alginate/halloysite nanotube (HNTs) composite scaffolds were prepared using a freeze-drying method. Amine treatment on the scaffold occurred through chemical methods, which in turn caused the hydroxyl groups to be replaced with carboxyl groups in chitosan and alginate, after which a reaction between ethylenediamine, 1-ethyl-3,(3-dimethylaminopropyl) carbodiimide (EDC) and scaffold triggered the amine groups to connect to the carboxyl groups of chitosan and alginate. The chemical structure, morphology and mechanical properties of the composite scaffolds were investigated by FTIR, CHNS, SEM/EDS and compression tests. The electrostatic attraction and hydrogen bonding between chitosan, alginate and halloysite was confirmed by FTIR spectroscopy. Chitosan/alginate/halloysite scaffolds exhibit significant enhancement in compressive strength compared with chitosan/alginate scaffolds. CHNS and EDS perfectly illustrate that amine groups were effectively introduced in the aminated scaffold. The growth and cell attachment of L929 cells as well as the cytotoxicity of the scaffolds were investigated by SEM and Alamar Blue (AB). The results indicated that the aminated chitosan/alginate/halloysite scaffold has better cell growth and cell adherence in comparison to that of chitosan/alginate/halloysite samples. Aminated chitosan/alginate/halloysite composite scaffolds exhibit great potential for applications in tissue engineering, ideally in

  14. Haemoglobin adducts formed by aromatic amines in smokers: sources of inter-individual variability.

    OpenAIRE

    Ronco, G.; Vineis, P; Bryant, M S; Skipper, P. L.; Tannenbaum, S R

    1990-01-01

    In a previous study we found that aromatic amines, particularly 4-aminobiphenyl, formed haemoglobin adducts at higher concentrations in the blood of smokers compared to non-smokers. We re-analyse here data on haemoglobin adducts of 14 aromatic amines in order to ascertain if the inter-individual variability left unexplained by tobacco smoking could be attributed to differences in individual metabolic patterns. For this purpose we computed residuals from analysis of variance in order to adjust...

  15. Heterogeneous Rhodium-Catalyzed Aerobic Oxidative Dehydrogenative Cross-Coupling: Nonsymmetrical Biaryl Amines.

    Science.gov (United States)

    Matsumoto, Kenji; Yoshida, Masahiro; Shindo, Mitsuru

    2016-04-18

    The first heterogeneously catalyzed oxidative dehydrogenative cross-coupling of aryl amines is reported herein. 2-Naphthylamine analogues were reacted with various electron-rich arenes using a heterogeneous Rh/C catalyst under mild aerobic conditions, thus affording nonsymmetrical biaryl amines in excellent yields with high selectivities. This reaction provides a mild, operationally simple, and efficient approach for the synthesis of biaryls which are important to pharmaceutical and materials chemistry. PMID:26996772

  16. Über den Einfluss biogener Amine auf unkonditionierten und konditionierten Stimulus

    OpenAIRE

    Buckemüller, Christina

    2014-01-01

    Biogenic amines play an important role in the modulation of behavior in vertebrates and invertebrates. Octopamine, a biogenic amine, exclusively for invertebrates is an important neurotransmitter and neuromodulator and has a considerable role as stress hormone. Octopamine plays a central role in learning and behavior in insects. The precise role in such behavior has been discussed over the last years. The signaling pathways of octopamine, tyramine and dopamine interact. Therefore, it is di...

  17. New procedure of selected biogenic amines determination in wine samples by HPLC

    International Nuclear Information System (INIS)

    Highlights: • We proposed new procedure for derivatization of biogenic amines. • The NMR and XRD analysis confirmed the purity and uniqueness of derivatives. • Concentration of biogenic amines in wine samples were analyzed by RP-HPLC. • Sample contamination and derivatization reactions interferences were minimized. - Abstract: A new procedure for determination of biogenic amines (BA): histamine, phenethylamine, tyramine and tryptamine, based on the derivatization reaction with 2-chloro-1,3-dinitro-5-(trifluoromethyl)-benzene (CNBF), is proposed. The amines derivatives with CNBF were isolated and characterized by X-ray crystallography and 1H, 13C, 19F NMR spectroscopy in solution. The novelty of the procedure is based on the pure and well-characterized products of the amines derivatization reaction. The method was applied for the simultaneous analysis of the above mentioned biogenic amines in wine samples by the reversed phase-high performance liquid chromatography. The procedure revealed correlation coefficients (R2) between 0.9997 and 0.9999, and linear range: 0.10–9.00 mg L−1 (histamine); 0.10–9.36 mg L-1 (tyramine); 0.09–8.64 mg L−1 (tryptamine) and 0.10–8.64 mg L−1 (phenethylamine), whereas accuracy was 97%–102% (recovery test). Detection limit of biogenic amines in wine samples was 0.02–0.03 mg L−1, whereas quantification limit ranged 0.05–0.10 mg L−1. The variation coefficients for the analyzed amines ranged between 0.49% and 3.92%. Obtained BA derivatives enhanced separation the analytes on chromatograms due to the inhibition of hydrolysis reaction and the reduction of by-products formation

  18. Study on biogenic amines in various dry salted fish consumed in China

    Science.gov (United States)

    Wu, Yanyan; Chen, Yufeng; Li, Laihao; Yang, Xianqing; Yang, Shaoling; Lin, Wanling; Zhao, Yongqiang; Deng, Jianchao

    2016-05-01

    This study was carried out to investigate the biogenic amines (BAs), physicochemical property and microorganisms in dry salted fish, a traditional aquatic food consumed in China. Forty three samples of dry salted fish were gathered from retail and wholesale markets and manufacturers, which had been produced in various regions in China. Cadaverine (CAD) and putrescine (PUT) were quantitatively the most common biogenic amines. About 14% of the samples exceeded the histamine content standards established by the FDA and/or EU. The highest histamine content was found in Silver pomfret (Pampus argenteus) (347.79 mg kg-1). Five of forty three samples exceeded the acceptable content of TYR (100 mg kg-1), and 23.26% of dried-salted fish contained high contents of biogenic amines (above 600 mg kg-1). In addition, species, regions, pickling processes and drying methods made the physicochemical property, microorganisms and biogenic amines in dry salted fish to be different to some extents. The total plate count (TPC) was much higher than that of total halophilic bacteria in all samples. The biogenic amines, physicochemical property and microbiological counts exhibited large variations among samples. Furthermore, no significant correlation between biogenic amines and physicochemical property and TPC was observed. This study indicated that dry salted fish may still present healthy risk for BAs, depending on the processing methods, storage conditions among others.

  19. Structure-Activity Relationships for Rates of Aromatic Amine Oxidation by Manganese Dioxide.

    Science.gov (United States)

    Salter-Blanc, Alexandra J; Bylaska, Eric J; Lyon, Molly A; Ness, Stuart C; Tratnyek, Paul G

    2016-05-17

    New energetic compounds are designed to minimize their potential environmental impacts, which includes their transformation and the fate and effects of their transformation products. The nitro groups of energetic compounds are readily reduced to amines, and the resulting aromatic amines are subject to oxidation and coupling reactions. Manganese dioxide (MnO2) is a common environmental oxidant and model system for kinetic studies of aromatic amine oxidation. In this study, a training set of new and previously reported kinetic data for the oxidation of model and energetic-derived aromatic amines was assembled and subjected to correlation analysis against descriptor variables that ranged from general purpose [Hammett σ constants (σ(-)), pKas of the amines, and energies of the highest occupied molecular orbital (EHOMO)] to specific for the likely rate-limiting step [one-electron oxidation potentials (Eox)]. The selection of calculated descriptors (pKa, EHOMO, and Eox) was based on validation with experimental data. All of the correlations gave satisfactory quantitative structure-activity relationships (QSARs), but they improved with the specificity of the descriptor. The scope of correlation analysis was extended beyond MnO2 to include literature data on aromatic amine oxidation by other environmentally relevant oxidants (ozone, chlorine dioxide, and phosphate and carbonate radicals) by correlating relative rate constants (normalized to 4-chloroaniline) to EHOMO (calculated with a modest level of theory). PMID:27074054

  20. Study on biogenic amines in various dry salted fish consumed in China

    Science.gov (United States)

    Wu, Yanyan; Chen, Yufeng; Li, Laihao; Yang, Xianqing; Yang, Shaoling; Lin, Wanling; Zhao, Yongqiang; Deng, Jianchao

    2016-08-01

    This study was carried out to investigate the biogenic amines (BAs), physicochemical property and microorganisms in dry salted fish, a traditional aquatic food consumed in China. Forty three samples of dry salted fish were gathered from retail and wholesale markets and manufacturers, which had been produced in various regions in China. Cadaverine (CAD) and putrescine (PUT) were quantitatively the most common biogenic amines. About 14% of the samples exceeded the histamine content standards established by the FDA and/or EU. The highest histamine content was found in Silver pomfret ( Pampus argenteus) (347.79 mg kg-1). Five of forty three samples exceeded the acceptable content of TYR (100 mg kg-1), and 23.26% of dried-salted fish contained high contents of biogenic amines (above 600 mg kg-1). In addition, species, regions, pickling processes and drying methods made the physicochemical property, microorganisms and biogenic amines in dry salted fish to be different to some extents. The total plate count (TPC) was much higher than that of total halophilic bacteria in all samples. The biogenic amines, physicochemical property and microbiological counts exhibited large variations among samples. Furthermore, no significant correlation between biogenic amines and physicochemical property and TPC was observed. This study indicated that dry salted fish may still present healthy risk for BAs, depending on the processing methods, storage conditions among others.

  1. IMPROVED INTERFACIAL BONDING OF PVC/WOOD-FLOUR COMPOSITES BY LIGNIN AMINE MODIFICATION

    Directory of Open Access Journals (Sweden)

    Xiaopeng Yue

    2011-04-01

    Full Text Available Soda lignin was divided into two fractions with different molecular weights by methanol extraction. Lignin amine was synthesized from the low-molecular-weight lignin fraction via Mannich reaction and was used for interfacial modification of poly-(vinylchloride (PVC/wood-flour composites. The PVC/wood-flour composites were prepared from surface-treated wood flour and PVC by melt compounding. The lignin amine treatment provided almost equivalent improvement in mechanical performances of composites as aminosilane treatment does. The tensile and impact strengths of composites prepared from 30phr of wood flour treated with 2wt% lignin amine were increased by 21.0% and 43.9%, respectively, compared to those prepared from untreated wood flour. Furthermore, lignin amine treatment could also significantly reduce the water absorption of composites. A significant increase in storage modulus (E’ was observed upon incorporation of wood flour with lignin amine treatment. The improved dispersion of wood flour in polymer matrix was observed by SEM images when the wood flour was treated by lignin amine. The experimental data indicate that the polymer-wood interfacial combination is strengthened.

  2. Preparation and adsorption property of aminated cross linking microbeads of GMA/EGDMA for bilirubin

    Indian Academy of Sciences (India)

    Zhiping Chen; Baojiao Gao; Xiaofeng Yang

    2009-11-01

    Cross linking microbeads with a controllable diameter were synthesized by suspension copolymerization of the monomer glycidyl methacrylate (GMA) and the cross linking agent ethylene glycol dimethylacrylate (EGDMA). By the ring-opening reaction of the epoxy groups, the microbeads GMA/EGDMA were modified with different aminating agents and resulting in the aminated microbeads. The morphology of the microbeads was characterized by SEM. The adsorption property of aminated microbeads for bilirubin was investigated, and the effects of various factors, such as the chemical structures of the aminating agents, pH values of the medium and the presence of bovine serum albumin in the adsorption medium, on the adsorption property were examined. The experimental results show that the aminated microbeads have strong adsorption ability for bilirubin, and the isotherm adsorption behaviour is fitted to Freundlich equation satisfactorily. The adsorption ability of the aminated microbeads modified with hexanediamine is stronger than that of others, and the longer the molecule of multi-ethylene multiamine, the weaker the adsorption ability for bilirubin. The pH value of the medium affects the adsorption ability greatly, as pH = 6, the adsorption ability is strongest. In the presence of BSA, the microbeads still have a higher adsorption capacity towards bilirubin.

  3. Full factorial design applied to intercalation of amines in lamellar titanium phenylphosphonate and titanium phenylarsonate

    International Nuclear Information System (INIS)

    The intercalation of amines into titanium phenylphosphonate M(O3PC6H5)2 and titanium phenylarsonate M(O3AsC6H5)2 was investigated through batch and back-titration processes. Amine insertion in both layered lamellar inorganic matrices, measured by the number of moles of intercalated agent, was optimized using a complete factorial design based on two levels and four factors. The effects of solvent, ethanol and acetonitrile, neutral organic base, ethyl and propylamines, H3C(CH2)nNH2 (n=1, 2), and material mass, 30 and 40 mg, on amine insertion in both lamellar inorganic matrices was optimized using a full factorial design. Important positive effect values, 0.40x10-3 and 0.69x10-3 mol g-1 were observed for inorganic material and solvent whereas a negative effect, -0.33x10-3 mol g-1 was observed for material mass. Two significant but less important binary interactions were also observed. The use of either ethyl or propylamine does not appear to affect the quantity of amine insertion. Recommended experimental conditions for maximum amine insertion obtained from this factorial design are 30 mg of titanium phenylarsonate in acetonitrile solvent using either of the studied amines

  4. The Significance of Biogenic Amines as Radio-Indicators in Experimental Animals with Reference to Man

    International Nuclear Information System (INIS)

    Although variable results have been obtained by various investigators, radiation-induced release of biogenic amines from several tissues in a variety of animals appears to be well established. Such a release will lead to enhanced blood levels and subsequendy give rise to an increase in the urinary excretion of the native compounds. To a certain extent the released bio-amines are broken down thus causing an increase in the urinary level of bio-amine metabolites. Apart from these two possibilities a minute quantity of the released amines seems to be trapped by adequate receptor sites introducing responses either of physiological or, by disturbing physiological processes based upon the normal delicately balanced release of bioamines, of a pathological nature. As such, the erythemal response, radiation sickness and a rise of body temperature may be mentioned. Recently, by employing pharmacological techniques, the irradiation-induced rise in body temperature was shown to be based upon the release of catecholamines in the rabbit and of serotonin in the cat. It is believed that this temperature response, which is maximal 2 to 3 hours following a radiation insult, might be evaluated as a simple, additional factor for indicating radiation injury, perhaps rather than the bio-amine compounds in urine. As such, biogenic amines might be worth studying more extensively in regard to recovery from radiation injury

  5. Managing your wine fermentation to reduce the risk of biogenic amine formation

    Directory of Open Access Journals (Sweden)

    Anita Yolandi Smit

    2012-03-01

    Full Text Available Biogenic amines are nitrogenous organic compounds produced in wine from amino acid precursors mainly by microbial decarboxylation. The concentration of biogenic amines that can potentially be produced is dependent on the amount of amino acid precursors in the medium, the presence of decarboxylase positive microorganisms and conditions that enable microbial or biochemical activity such as the addition of nutrients to support the alcoholic and malolactic fermentation (MLF inoculated starter cultures. MLF can be conducted using co-inoculation or inoculated after the completion of alcoholic fermentation (AF that may also affect the level of biogenic amine in the wine. This study focussed on the impact the addition of complex commercial yeast and bacterial nutrients and the use of different MLF inoculation scenarios could have on the production of biogenic amine in the wine. Results obtained with wine showed that in this study the amine that was influenced by nutrient addition was histamine. In the synthetic winemaking using 12 different treatments no clear tendencies were observed. It was shown that in certain conditions co-inoculation could reduce the amount of biogenic amines produced.

  6. New procedure of selected biogenic amines determination in wine samples by HPLC.

    Science.gov (United States)

    Piasta, Anna M; Jastrzębska, Aneta; Krzemiński, Marek P; Muzioł, Tadeusz M; Szłyk, Edward

    2014-06-27

    A new procedure for determination of biogenic amines (BA): histamine, phenethylamine, tyramine and tryptamine, based on the derivatization reaction with 2-chloro-1,3-dinitro-5-(trifluoromethyl)-benzene (CNBF), is proposed. The amines derivatives with CNBF were isolated and characterized by X-ray crystallography and (1)H, (13)C, (19)F NMR spectroscopy in solution. The novelty of the procedure is based on the pure and well-characterized products of the amines derivatization reaction. The method was applied for the simultaneous analysis of the above mentioned biogenic amines in wine samples by the reversed phase-high performance liquid chromatography. The procedure revealed correlation coefficients (R(2)) between 0.9997 and 0.9999, and linear range: 0.10-9.00 mg L(-1) (histamine); 0.10-9.36 mg L(-1) (tyramine); 0.09-8.64 mg L(-1) (tryptamine) and 0.10-8.64 mg L(-1) (phenethylamine), whereas accuracy was 97%-102% (recovery test). Detection limit of biogenic amines in wine samples was 0.02-0.03 mg L(-1), whereas quantification limit ranged 0.05-0.10 mg L(-1). The variation coefficients for the analyzed amines ranged between 0.49% and 3.92%. Obtained BA derivatives enhanced separation the analytes on chromatograms due to the inhibition of hydrolysis reaction and the reduction of by-products formation. PMID:24928246

  7. Characterization of collagen fiber grafted with glycidyl methacrylate monomer and treated with dibutyl amine

    International Nuclear Information System (INIS)

    Leather grafted with poly (glycidyl methacrylate) (L-g-PGMA) having graft yield of 26% and epoxy content 69.4 m mol/ 100 gm was prepared according to the emulsion polymerization technique and impregnated in different dibutyl amine solutions using amine/ epoxy molar ratio range from 0.5 up to 2.5. The obtained samples were characterized with respect to the nitrogen content, infrared spectroscopy, thermogravimetric analysis (TGA) analysis and the scanning electron microscope. The nitrogen content of the treated leather samples was increased by increasing the dibutyl amine concentration up to amine/ epoxy molar ratio of 2 after which it began to decrease. The water absorption, tensile strength and elongation (%) as well as hardness of the modified leather samples were studied and compared with the unmodified one. The colour strength values of dyed leather samples with acid dye were increased by grafting or by increasing the amine/epoxy molar ratio up to a value of 1.0 after which it begin to decrease. Meanwhile, the colour strength value of dyed leather sample with reactive dye was sharply decreased after grafting with poly (glycidyl methacrylate). On the other hand, pronounced increment in the colour strength value was obtained for the samples grafted with glycidyl methacrylate and treated with dibutyl acrylate amine and the colour strength is directly proportional to the sample nitrogen content

  8. Dynamics of CO 2 Adsorption on Amine Adsorbents. 2. Insights Into Adsorbent Design

    KAUST Repository

    Bollini, Praveen

    2012-11-21

    Packed bed breakthrough experiments are reported for commercial zeolite 13X and 3-aminopropyl-functionalized SBA-15 silica materials with three different amine loadings. Mass and heat transfer dynamics for all four materials are modeled successfully. Amine adsorbents with open pores are found to exhibit faster mass diffusion rates compared to zeolite 13X. When amine loading is increased by coupling aminopropyl groups, premature breakthrough combined with a long tail is observed. Contrary to conventional physisorbants, finite heat losses to the column wall do not explain the long breakthrough tail. A rate model that accounts for heterogeneity in diffusion was found to accurately capture the breakthrough shape of the high loading material. Batch uptake measurements support the hypothesis that slow diffusion through the polymer phase is what hampers adsorption kinetics in the high amine loading adsorbent. The results emphasize the importance of designing materials that are not overloaded with amine sites, as excessive amine loadings can lead to depressed adsorption kinetics and premature column breakthrough. © 2012 American Chemical Society.

  9. Heterogeneous Ru-Based Catalysts for One-Pot Synthesis of Primary Amines from Aldehydes and Ammonia

    Directory of Open Access Journals (Sweden)

    Bo Dong

    2015-12-01

    Full Text Available The direct reductive amination of carbonyl compounds with NH3 and H2 is an alternative route to produce primary amines in practical production. The search for efficient and selective catalysts has attracted great interest. In the present work, the reductive amination of heptaldehyde with NH3 was investigated over a Ru-based catalyst. The product selectivities were found to be related with the supports of Ru. The alumina with spinel structure (γ-Al2O3, θ-Al2O3-supported Ru catalysts exhibited selectivity favoring primary amines (94% yield at 100% heptaldehyde conversion under optimal conditions. Purely basic (MgO, CaO and relative acidic (Nb2O5, SnO2, MCM-41, HZSM-5 supports showed relatively poor selectivity towards primary amines (0%–53% yield. The reductive amination mechanism was also proposed. The Schiff base N-[heptylene]heptyl-1-amine was a key intermediate. Ru/γ-Al2O3 was shown to be an excellent hydrogenolysis catalyst to selectively produce primary amine by amination and hydrogenolysis of N-[heptylene]heptyl-1-amine.

  10. Influence of Dissolved Metals on N-Nitrosamine Formation under Amine-based CO2 Capture Conditions.

    Science.gov (United States)

    Wang, Zimeng; Mitch, William A

    2015-10-01

    As the prime contender for postcombustion CO2 capture technology, amine-based scrubbing has to address the concerns over the formation of potentially carcinogenic N-nitrosamine byproducts from reactions between flue gas NOx and amine solvents. This bench-scale study evaluated the influence of dissolved metals on the potential to form total N-nitrosamines in the solvent within the absorber unit and upon a pressure-cooker treatment that mimics desorber conditions. Among six transition metals tested for the benchmark solvent monoethanolamine (MEA), dissolved Cu promoted total N-nitrosamine formation in the absorber unit at concentrations permitted in drinking water, but not the desorber unit. The Cu effect increased with oxygen concentration. Variation of the amine structural characteristics (amine order, steric hindrance, -OH group substitution and alkyl chain length) indicated that Cu promotes N-nitrosamine formation from primary amines with hydroxyl or carboxyl groups (amino acids), but not from secondary amines, tertiary amines, sterically hindered primary amines, or amines without oxygenated groups. Ethylenediaminetetraacetate (EDTA) suppressed the Cu effect. The results suggested that the catalytic effect of Cu may be associated with the oxidative degradation of primary amines in the absorber unit, a process known to produce a wide spectrum of secondary amine products that are more readily nitrosatable than the pristine primary amines, and that can form stable N-nitrosamines. This study highlighted an intriguing linkage between amine degradation (operational cost) and N-nitrosamine formation (health hazards), all of which are challenges for commercial-scale CO2 capture technology. PMID:26335609

  11. Variations in product in reactions of naphthoquinone with primary amines

    Directory of Open Access Journals (Sweden)

    Barooah Nilotpal

    2007-03-01

    Full Text Available Abstract Reaction of 1,2-naphthoquinone with primary amines gives a 2-amino-1,4-naphthoquinone derivative which is equivalent to 1,2 to 1,4 carbonyl transposition. For example the reaction of 1,2-naphthoquinone with 4-methoxyaniline gives 2-(4-methoxyanilino-naphthoquinone-1,4-(4-methoxyanil (1 and with n-butylamine gives 2-(butylamino-naphthoquinone-1,4-butylimine (2 respectively. The compounds 1 and 2 are characterized by X-ray crystallography; they have hydrogen-bonded dimeric structures. Similar reaction of 1,4-naphthoquinone with 3-picolylamine and 4-picolylamine gives the corresponding 2-amino 1,4-naphthoquinones; two products are characterized by X-ray crystallography. The reaction of 1,4-naphthoquinone with 4-aminothiophenol and 1,4-naphthoquinone with 4-aminophenol are compared. The former leads to C-S and the latter to C-N bond formation. The reaction of 1,4-naphthoquinone with 4-aminothiophenol in an NMR tube is studied to explain that 2-(4-anilinothiolato 1,4-naphthoquinone derivative to be the sole product in the reaction.

  12. Electrochemical characterization of platinum nanoparticles stabilized by amines

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez-Meneses, E., E-mail: esthervincent@yahoo.co [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Dominguez-Crespo, M.A. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Montiel-Palma, V. [Centro de Investigaciones Quimicas, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001, Colonia Chamilpa, C.P. 62201 Cuernavaca, Morelos (Mexico); Chavez-Herrera, V.H. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Gomez, E. [Instituto de Quimica-Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, C.P. 04510 Mexico, D.F. (Mexico); Hernandez-Tapia, G. [Gerencia de Catalizadores y Proceso, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas norte 152, 07730 Mexico, D.F. (Mexico)

    2009-08-26

    In this work we present the synthesis by Chaudret approach of Pt nanoparticles stabilized by primary amine (-NH{sub 2}) compounds. Their electrochemical performance as cathodes in low temperature polymer electrolite fuel cells on the oxygen reduction reaction (ORR) is also presented. Transmission electron microscopy (TEM) images of the samples show Pt nanostructures with particle size varying from 10 to 100 nm depending on the kind of the stabilizer used during the catalyst preparation. In some cases well-dispersed isolated platinum nanoparticles were observed. The activity of the dispersed catalysts (Pt/C) with respect to the ORR was investigated using steady state polarization measurements. The kinetic parameters showed that although no significant differences between the Tafel slopes of the Pt catalysts exist, transfer coefficients and exchange current densities show higher activities when the Pt nanoparticles were stabilized by tert-butylamine (TBA). The performance with respect to the ORR of the Pt/C catalyst on vulcan carbon substrate is active and comparable to that reported in the literature for state-of-art electrocatalysts.

  13. Electrochemical characterization of platinum nanoparticles stabilized by amines

    International Nuclear Information System (INIS)

    In this work we present the synthesis by Chaudret approach of Pt nanoparticles stabilized by primary amine (-NH2) compounds. Their electrochemical performance as cathodes in low temperature polymer electrolite fuel cells on the oxygen reduction reaction (ORR) is also presented. Transmission electron microscopy (TEM) images of the samples show Pt nanostructures with particle size varying from 10 to 100 nm depending on the kind of the stabilizer used during the catalyst preparation. In some cases well-dispersed isolated platinum nanoparticles were observed. The activity of the dispersed catalysts (Pt/C) with respect to the ORR was investigated using steady state polarization measurements. The kinetic parameters showed that although no significant differences between the Tafel slopes of the Pt catalysts exist, transfer coefficients and exchange current densities show higher activities when the Pt nanoparticles were stabilized by tert-butylamine (TBA). The performance with respect to the ORR of the Pt/C catalyst on vulcan carbon substrate is active and comparable to that reported in the literature for state-of-art electrocatalysts.

  14. Ultrafast Structural Dynamics of Tertiary Amines upon Electronic Excitation

    Science.gov (United States)

    Cheng, Xinxin; Minitti, Michael P.; Deb, Sanghamitra; Zhang, Yao; Budarz, James; Weber, Peter M.

    2011-06-01

    The structural response of several tertiary amines to electronic excitation has been investigated using Rydberg Fingerprint Spectroscopy. The 3p Rydberg states are reached by excitation with a 5.93 eV photon while 3s states are populated by electronic relaxation from 3p state. We observe binding energy shifts on ultrafast time scales in all peaks that reflect the structural change of the molecular ion cores. The shifts are in the range of 15 meV to 30 meV, within time scales of less than 500 fs, depending on the specific molecular systems and the nature of the electronic state. In cases where the p states are spectrally separate, the trends of the energy shifts are different for the p_z and p_x_y Rydberg states whereas the p_z and s states are similar. This suggests that the response of the Rydberg states to structural displacements depends on the symmetry. Very fast binding energy shifts, observed on sub-picosecond time scales, are attributed to the structural adjustment from a pyramidal to a planar structure upon Rydberg excitation. The quantitative values of the binding energy shifts can also be affected by laser chirp, which we model using simulations.

  15. Adenosine Amine Congener as a Cochlear Rescue Agent

    Directory of Open Access Journals (Sweden)

    Srdjan M. Vlajkovic

    2014-01-01

    Full Text Available We have previously shown that adenosine amine congener (ADAC, a selective A1 adenosine receptor agonist, can ameliorate noise- and cisplatin-induced cochlear injury. Here we demonstrate the dose-dependent rescue effects of ADAC on noise-induced cochlear injury in a rat model and establish the time window for treatment. Methods. ADAC (25–300 μg/kg was administered intraperitoneally to Wistar rats (8–10 weeks old at intervals (6–72 hours after exposure to traumatic noise (8–16 kHz, 110 dB sound pressure level, 2 hours. Hearing sensitivity was assessed using auditory brainstem responses (ABR before and 12 days after noise exposure. Pharmacokinetic studies investigated ADAC concentrations in plasma after systemic (intravenous administration. Results. ADAC was most effective in the first 24 hours after noise exposure at doses >50 μg/kg, providing up to 21 dB protection (averaged across 8–28 kHz. Pharmacokinetic studies demonstrated a short (5 min half-life of ADAC in plasma after intravenous administration without detection of degradation products. Conclusion. Our data show that ADAC mitigates noise-induced hearing loss in a dose- and time-dependent manner, but further studies are required to establish its translation as a clinical otological treatment.

  16. Membrane Separation of 2-Ethyl Hexyl Amine/1-Decene

    KAUST Repository

    Bawareth, Bander

    2012-12-01

    1-Decene is a valuable product in linear alpha olefins plants that is contaminated with 2-EHA (2-ethyl hexyl amine). Using organic solvent nanofiltration membranes for this separation is quite challengeable. A membrane has to be a chemically stable in this environment with reasonable and stable separation factor. This paper shows that Teflon AF 2400 and cellulose acetate produced interesting results in 1-decene/2-EHA separation. The separation factor of Teflon AF 2400 is 3 with a stable permeance of 1.1x10-2 L/(m2·h·bar). Likewise, cellulose acetate gave 2-EHA/1-decene separation factor of 2 with a lower permeance of 3.67x10-3 L/(m2·h·bar). A series of hydrophilic membranes were tested but they did not give any separation due to high degree of swelling of 2-EHA with these polymers. The large swelling causes the membrane to lose its diffusivity selectivity because of an increase in the polymer\\'s chain mobility.

  17. Heterocyclic amine content in commercial ready to eat meat products.

    Science.gov (United States)

    Puangsombat, Kanithaporn; Gadgil, Priyadarshini; Houser, Terry A; Hunt, Melvin C; Smith, J Scott

    2011-06-01

    Heterocyclic amines (HCAs) are produced in meats cooked at high temperature, which are potent mutagens and a risk factor for human cancers. The aim of this study was to estimate the amount of HCAs in some commonly consumed ready-to-eat (RTE) meat products. The RTE products were purchased from a local grocery store, and HCA were analyzed using an analytical method based on solid-phase extraction followed by HPLC. The primary HCAs in these samples were PhIP (2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine) (not detected-7.9 ng/g) and MeIQx (2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline) (not detected-3.6 ng/g). Products ranked in order of increasing total HCA content: pepperoni (0.05 ng/g)

  18. Depletion of florfenicol and florfenicol amine residues in chicken eggs.

    Science.gov (United States)

    Filazi, A; Sireli, U T; Yurdakok, B; Aydin, F G; Kucukosmanoglu, A G

    2014-01-01

    1. The aim of this study was to develop a suitable method for the analysis of florfenicol (FF) and its metabolite florfenicol amine (FFA) in chicken eggs and to determine FF and FFA residue depletion in eggs of laying hens. 2. The analytes were extracted from yolk, albumen and whole egg by phosphate buffer and ethyl acetate. Following purification, samples were analysed by high-performance liquid chromatography. 3. Fifty laying hens were divided into 5 groups, and each hen received doses of 20 mg/kg FF: Group 1 (received a single oral dose by gavage); Group 2 (a single intramuscular dose); Group 3 (a single subcutaneous dose); Group 4 (multiple oral doses for 3 d) and Group 5 (multiple oral doses for 5 d). 4. Limits of detection and of quantitation values were 1.94 and 6.45 g/10(9) g (ppb) for FF, respectively, and 0.48 and 1.58 ppb for FFA, respectively. Relative standard deviation values of intra-day and inter-day variation below 11% also confirmed the usefulness of the method for analysing FF and FFA in eggs. 5. From the first day of both oral and parenteral administration, FF and FFA were detected at 0.1% and 0.08% of dosage, respectively, and 57% of the drugs were eliminated from the egg yolk. Elimination time of FF was 8 d in Groups 1, 2 and 3; 9 d in Group 4 and 10 d in Group 5. PMID:24945307

  19. Synthesis, Characterization, and Pharmacological Evaluation of Selected Aromatic Amines

    Directory of Open Access Journals (Sweden)

    Hammad Ismail

    2015-01-01

    Full Text Available Aromatic amines 1-amino-4-phenoxybenzene (A-1A, 2-(4-aminophenoxy naphthalene (A-2A, and 1-(4-aminophenoxy naphthalene (A-3A were synthesized by the reduction of corresponding nitroaromatics with hydrazine monohydrate and Pd/C 5% (w/w. The newly synthesized compounds were characterized by FTIR, 1H NMR, 13C NMR, UV-visible spectrophotometer, and mass spectrometry and their biological activities were investigated along with structurally similar 4-(4-aminophenyloxy biphenyl (A-A. Results of brine shrimp cytotoxicity assay showed that almost all of the compounds had LD50 values <1 μg/mL. The compounds also showed significant antitumor activity with IC50 values ranging from 67.45 to 12.2 µgmL−1. The cytotoxicity and antitumor studies correlate the results which suggests the anticancerous nature of compounds. During the interaction study of these compounds with DNA, all of the compounds showed hyperchromic effect indicating strong interaction through binding with the grooves of DNA. Moreover, A-3A also showed decrease in λmax confirming higher propensity for DNA groove binding. In DPPH free radical scavenging assay, all the compounds showed potential antioxidant capability. The compounds were highly active in protecting DNA against hydroxyl free radicals. DNA interaction and antioxidant results back up each other indicating that these compounds have potential to be used as cancer chemopreventive agents. Additionally, one compound (A-1A showed significant antibacterial and antifungal activity as well.

  20. Renalase Prevents AKI Independent of Amine Oxidase Activity

    Science.gov (United States)

    Wang, Ling; Velazquez, Heino; Moeckel, Gilbert; Chang, John; Ham, Ahrom; Lee, H. Thomas; Safirstein, Robert

    2014-01-01

    AKI is characterized by increased catecholamine levels and hypertension. Renalase, a secretory flavoprotein that oxidizes catecholamines, attenuates ischemic injury and the associated increase in catecholamine levels in mice. However, whether the amine oxidase activity of renalase is involved in preventing ischemic injury is debated. In this study, recombinant renalase protected human proximal tubular (HK-2) cells against cisplatin- and hydrogen peroxide–induced necrosis. Similarly, genetic depletion of renalase in mice (renalase knockout) exacerbated kidney injury in animals subjected to cisplatin-induced AKI. Interestingly, compared with the intact renalase protein, a 20–amino acid peptide (RP-220), which is conserved in all known renalase isoforms, but lacks detectable oxidase activity, was equally effective at protecting HK-2 cells against toxic injury and preventing ischemic injury in wild-type mice. Furthermore, in vitro treatment with RP-220 or recombinant renalase rapidly activated Akt, extracellular signal-regulated kinase, and p38 mitogen-activated protein kinases and downregulated c-Jun N-terminal kinase. In summary, renalase promotes cell survival and protects against renal injury in mice through the activation of intracellular signaling cascades, independent of its ability to metabolize catecholamines, and we have identified the region of renalase required for these effects. Renalase and related peptides show potential as therapeutic agents for the prevention and treatment of AKI. PMID:24511138

  1. Technological Factors Affecting Biogenic Amine Content in Foods: A Review.

    Science.gov (United States)

    Gardini, Fausto; Özogul, Yesim; Suzzi, Giovanna; Tabanelli, Giulia; Özogul, Fatih

    2016-01-01

    Biogenic amines (BAs) are molecules, which can be present in foods and, due to their toxicity, can cause adverse effects on the consumers. BAs are generally produced by microbial decarboxylation of amino acids in food products. The most significant BAs occurring in foods are histamine, tyramine, putrescine, cadaverine, tryptamine, 2-phenylethylamine, spermine, spermidine, and agmatine. The importance of preventing the excessive accumulation of BAs in foods is related to their impact on human health and food quality. Quality criteria in connection with the presence of BAs in food and food products are necessary from a toxicological point of view. This is particularly important in fermented foods in which the massive microbial proliferation required for obtaining specific products is often relater with BAs accumulation. In this review, up-to-date information and recent discoveries about technological factors affecting BA content in foods are reviewed. Specifically, BA forming-microorganism and decarboxylation activity, genetic and metabolic organization of decarboxylases, risk associated to BAs (histamine, tyramine toxicity, and other BAs), environmental factors influencing BA formation (temperature, salt concentration, and pH). In addition, the technological factors for controlling BA production (use of starter culture, technological additives, effects of packaging, other non-thermal treatments, metabolizing BA by microorganisms, effects of pressure treatments on BA formation and antimicrobial substances) are addressed. PMID:27570519

  2. Enhanced adsorption of quaternary amine using modified activated carbon.

    Science.gov (United States)

    Prahas, Devarly; Wang, M J; Ismadji, Suryadi; Liu, J C

    2014-01-01

    This study examined different methodologies to modify activated carbon (AC) for the removal of quaternary amine, tetramethylammonium hydroxide (TMAH), from water. Commercial carbon (WAC) was treated by nitric acid oxidation (NA-WAC), silica impregnation (SM-WAC0.5), and oxygen plasma (P10-WAC), and their characteristics and adsorption capacity were compared. The Langmuir model fitted the equilibrium adsorption data well under different pH. The maximum adsorption capacity of WAC was 27.77 mg/g, while those of NA-WAC, SM-WAC 0.5, and P10-WAC were 37.46, 32.83 and 29.03 mg/g, respectively. Nitric acid oxidation was the most effective method for enhancing the adsorption capacity of TMAH. Higher pH was favorable for TMAH adsorption. Desorption study revealed that NA-WAC had no considerable reduction in performance even after five cycles of regeneration by 0.1 N hydrochloric acid. It was proposed that electrostatic interaction was the main mechanism of TMAH adsorption on activated carbon. PMID:24845325

  3. Biotinylated dextran amine anterograde tracing of the canine corticospinal tract

    Institute of Scientific and Technical Information of China (English)

    Xiao Han; Guangming Lv; Huiqun Wu; Dafeng Ji; Zhou Sun; Yaofu Li; Lemin Tang

    2012-01-01

    In this study, biotinylated dextran amine (BDA) was microinjected into the left cortical motor area of the canine brain. Fluorescence microscopy results showed that a large amount of BDA-labeled pyramidal cells were visible in the left cortical motor area after injection. In the left medulla oblongata, the BDA-labeled corticospinal tract was evenly distributed, with green fluorescence that had a clear boundary with the surrounding tissue. The BDA-positive corticospinal tract entered into the right lateral funiculus of the spinal cord and descended into the posterior part of the right lateral funiculus, close to the posterior horn, from cervical to sacral segments. There was a small amount of green fluorescence in the sacral segment. The distribution of BDA labeling in the canine central nervous system was consistent with the course of the corticospinal tract. Fluorescence labeling for BDA gradually diminished with time after injection. Our findings indicate that the BDA anterograde tracing technique can be used to visualize the localization and trajectory of the corticospinal tract in the canine central nervous system.

  4. Enhanced mercury ion adsorption by amine-modified activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Jianzhong [Center of Environmental Sciences, Lincoln University of Missouri, Jefferson City, MO 65102 (United States); Yang, John, E-mail: yangj@lincolnu.edu [Center of Environmental Sciences, Lincoln University of Missouri, Jefferson City, MO 65102 (United States); Deng Baolin [Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO 65211 (United States)

    2009-07-30

    Mercury (Hg) is one of the most toxic metals found in water and sediments. In an effort to develop an effective adsorbent for aqueous Hg removal, activated carbon (AC) was modified with an amino-terminated organosilicon (3-aminopropyltriethoxysilane, APTES). Surface properties of the APTES-modified AC (MAC) were characterized by the scanning electron microscopy in conjunction with the energy-dispersive spectroscopy (SEM-EDS), the Fourier transform infrared spectroscopy (FT-IR), and potentiometry. The impacts of solvent, APTES concentration, reactive time and temperature on the surface modification were evaluated. The aqueous Hg adsorptive kinetics and capacity were also determined. Results demonstrated that the strong Hg-binding amine ligands were effectively introduced onto the AC surfaces through the silanol reaction between carbon surface functional groups (-COOH, -COH) and APTES molecules. The modification lowered the pH at the point of zero charge (pH{sub pzc}) to 4.54 from 9.6, favoring cation adsorption. MAC presented a faster rate of the Hg (II) adsorption and more than double adsorptive capacity as compared with AC.

  5. Treatment of sewage containing aromatic amines with participation of macrophytes. Pt. 1. Mechanisms and kinetics of the elimination of aromatic amines by macrophytes

    Energy Technology Data Exchange (ETDEWEB)

    Timofeeva, S.S.; Kashina, N.F.

    1987-01-01

    Results are presented of studying quantitative regularities of utilizing aromatic amines (benzidine, ..cap alpha..-naphthylamine) by Chara algae (Nitella spec., Chara fragilis) and higher aquatic plants (Elodea candensis). It is shown that the basic part of eliminated benzidine is subjected to oxidative conversions under the action of macrophyte enzyme systems. Not more than 20% of eliminated benzidine accumulate in vegetative tissues.

  6. Synthesis, characterization, and application of silica supported ionic liquid as catalyst for reductive amination of cyclohexanone with formic acid and triethyl amine as hydrogen source

    Institute of Scientific and Technical Information of China (English)

    Ashif H. Tamboli; Avinash A. Chaugule; Faheem A. Sheikh; Wook-Jin Chung; Hern Kim

    2015-01-01

    A silica supported ionic liquid was synthesized and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, X-ray diffraction, N2 adsorption-desorption, and thermogravimetric analysis. All these techniques, especially SEM results indicated the presence of well-defined spherical particles having diameters larger than the pristine silica particles, confirming the successful immobilization of the ionic liquid. The prepared silica supported ionic liquid was used in the reductive amination of cyclohexanone under different conditions with different azeo-tropic mixtures of formic acid and triethyl amine as a hydrogen source. The catalyst showed effi-cient catalytic performance and excellent yields of N-cyclohexyl amine derivatives in the range of 58%to 84%at 30 °C. After completion of the reaction, the catalyst was easily recovered by simple filtration and reused for another five cycles without any significant impact on product yields. The obtained catalytic performance indicates that the present catalyst is green, very active, and reusable for the reductive amination of cyclohexanone.

  7. Solvent extraction studies on uranium using amine based extractants and recovery from low grade ore leach liquors

    International Nuclear Information System (INIS)

    In this study, amine based extractants (Alamine 336, Alamine 308, Alamine 304 and Aliquat 336) diluted in kerosene were used as promising extractants for uranium extraction and separation from other associated elements. Alamine 336 was the best extractant for uranium extraction process from sulfate solutions when compared with other amine based extractants, Alamine 308, Alamine 304 and Aliquat 336. Synergistic extraction behavior was studied with amines as extractants as well as synergist and organophosphorus reagents used as synergist mixed with amines. Synergistic extraction studies with amines were not suitable with each other for better extraction efficiency. However, amines mixed with organophosphorus extractants gave positive synergetic behavior with the highest synergistic coefficient 0.567 calculated from results obtained. The developed methodology was applied to uranium low grade ore processing and 99.83% of uranium was recovered without the interferences of other metals. (author)

  8. New CO2 adsorbent containing aminated poly(glycidyl methacrylate) grafted onto irradiated PE-PP nonwoven sheet

    International Nuclear Information System (INIS)

    A new CO2 adsorbent containing triethylamine (TEA) was prepared by radiation induced grafting of glycidyl methacrylate (GMA) onto polyethylene coated polypropylene (PE-PP) non-woven sheet followed by amination reaction. The degree of grafting (DOG%) was controlled by variation of monomer concentration and absorbed dose. The incorporation of aminated poly(GMA) was investigated by Fourier transform infrared (FTIR) and scanning electron microscope (SEM). The adsorbent with DOG of 350% and amination yield of 60% exhibited CO2 adsorption capacity of 4.52 mol/kg at ambient temperature and pressure. - Highlights: • Preparation of a new aminated fibrous adsorbent for CO2 capturing. • Grafting of GMA onto PP-PE nonwoven sheet followed by amination. • Dependence of degree of grafting on monomer concentration and absorbed dose. • FTIR and SEM evidences of grafting and amination. • CO2 adsorbent with high adsorption capacity at ambient temperature and pressure

  9. Chemical role of amines in the colloidal synthesis of CdSe quantum dots and their luminescence properties

    International Nuclear Information System (INIS)

    The role of organic amines in the colloidal synthesis of CdSe quantum dots (QDs) has been studied. CdSe QDs were synthesized from the source solutions containing 5 vol% of amines having various alkyl chain lengths, stereochemical sizes and electron donation abilities. The role of the additional amines was evaluated on the basis of the photoluminescence (PL) properties such as PL wavelength and intensity of the obtained CdSe QDs. The observed PL spectra were explained by the fact that the amines behaved as capping ligands on the surface of the QDs in the product colloidal solution and complex ligands for cadmium in the source solutions. It was shown that the particle size was controlled by the diffusion process depending on the mass and stereochemical shape of the amines, and the luminescence intensity increased with the increasing electron donation ability and capping density of the amines

  10. Synthesis and characterization of aminated perfluoro polymer electrolytes

    Science.gov (United States)

    Page-Belknap, Zachary Stephan Glenn

    Polymer electrolytes have been developed for use in anion exchange membrane fuel cells for years. However, due to the highly corrosive environment within these fuel cells, poor chemical stability of the polymers and low ion conductivity have led to high development costs and thus prevention from widespread commercialization. The work in this study aims to provide a solution to these problems through the synthesis and characterization of a novel polymer electrolyte. The 800 EW 3M PFSA sulfonyl fluoride precursor was aminated with 3-(dimethylamino)-1-propylamine to yield a functional polymer electrolyte following quaternization, referred to in this work as PFSa-PTMa. 1 M solutions of LiPF6, HCL, KOH, NaOH, CsOH, NaHCO3 and Na2CO3 were used to exchange the polymer to alternate counterion forms. Chemical structure analysis was performed using both FT and ATR infrared spectroscopy to confirm sulfonyl fluoride replacement and the absence of sulfonic acid sites. Mechanical testing of the polymer, following counterion exchange with KOH, at saturated conditions and 60 ºC exhibited a tensile strength of 13 +/- 2.0 MPa, a Young's modulus of 87 +/- 16 MPa and a degree of elongation reaching 75% +/- 9.1%, which indicated no mechanical degradation following exposure to a highly basic environment. Conductivities of the polymer in the Cl- and OH- counterion forms at saturated conditions and 90 ºC were observed at 26 +/- 8.0 mS cm-1 and 1.1 +/- 0.1 mS cm-1, respectively. OH- conductivities were slightly above those observed for CO32- and HCO 3- counterions at the same conditions, 0.63 +/- 0.18 and 0.66 +/- 0.21 mS cm-1 respectively. The ion exchange capacity (IEC) of the polymer in the Cl- counterion form was measured via titration at 0.57 meq g-1 which correlated to 11.2 +/- 0.10 water molecules per ion site when at 60ºC and 95% relative humidity. The IEC of the polymer in the OH- counterion form following titration expressed nearly negligible charge density, less than 0.01 meq

  11. Metal Monolithic Amine-grafted Zeolite for CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Steven

    2011-03-31

    The solid amine sorbent for CO{sub 2} capture process has advantages of simplicity and low operating cost compared to the MEA (monoethanolamine) process. Solid amine sorbents reported so far suffered from either low CO{sub 2} capture capacity or low stability. The solid amine sorbent developed in this project exhibited more than 3.2 mmol/g and degraded less than 10% even after 500 cycles of heating and cooling in absence of steam. The presence of steam further enhanced CO{sub 2} capture capacity. The cost of the sorbent is estimated to be less than $7.00/lb. This sorbent was developed using the results of in situ infrared spectroscopic study. Infrared results showed that CO{sub 2} adsorbs on TEPA (tetraethylenepentamine)/PEG (polyethylene glycol) as carbamates and bicarbonates. The CO{sub 2} adsorption capacity and oxidation resistance of the amine sorbent can be enhanced by the interactions between NH{sub 2} of TEPA molecules with the OH group of PEG molecules. PEG was also found to be effectively disperse and immobilize the aromatic amines for SO{sub 2} adsorption. The infrared study also showed that SiO{sub 2} is a significantly better support than zeolites due to its proper hydrophobicity. The results of this study led to the development of a high performance solid amine sorbent under simulated gas flow condition in a fixed bed, a fluidized bed, and a metal monolith unit. This study showed heat transfer could become a major technical issue in scaling up a fixed bed adsorber. The use of the fluidized bed and metal monoliths can alleviate the heat transfer issue. The metal monolith could be suitable for small scale applications due to the high cost of manufacturing; the fluidized bed mode would be most suitable for large scale applications. Preliminary economic analysis suggested that the Akron solid amine process would cost 45% less than that of MEA process.

  12. The effect of aliphatic amines on the extraction of elements by phosphoryl-containing podands from hydrochloric acid media

    International Nuclear Information System (INIS)

    Distribution of Sc, Zn, Ga, Mo, Pd, Ag, Cd, In, Pt, Hg, Pb, Bi and U between HCl aqueous solutions and mixtures of phosphoryl-containing podands with aliphatic amines in dichloroethane is studied by the production of phosphoryl-containing podand complexes with a protonated amine molecule in the organic phase, which represent a cation section of extracted ion associates. Effect of amine and podand nature and HCl concentration on element extraction is considered. (author)

  13. PCDD/Fs' suppression by sulfur-amine/ammonium compounds.

    Science.gov (United States)

    Fu, Jian-Ying; Li, Xiao-Dong; Chen, Tong; Lin, Xiao-Qing; Buekens, Alfons; Lu, Sheng-Yong; Yan, Jian-Hua; Cen, Ke-Fa

    2015-03-01

    Three distinct -S and -NH2 or NH4(+) containing compounds, including ammonium thiosulfate, aminosulfonic acid and thiourea, were studied as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) inhibitors. All these three -S and -N containing compounds tested show strong suppression of PCDD/Fs formation, especially for thiourea which has not been studied before. With a (S+N)/Cl molar ratio of only 0.47, thiourea could inhibit 97.3% of PCDD/Fs and even 99.8% of I-TEQ. At an unusually high de novo test temperature (650 °C), the PCDD/Fs' formation was still very low but also the inhibition capacity of thiourea was weak, with an efficiency of 59% for PCDD/Fs when with a (S+N)/Cl molar ratio of 1.40. The results also revealed that the inhibition capability of the combined -S/-NH2 or -S/NH4(+) suppressant was strongly influenced by both the nature of the functional group of nitrogen and the value of the molar ratio (S+N)/Cl. The amine functional group -NH2 tends to be more efficient than ammonium NH4(+) and within a certain range a higher (S+N)/Cl value leads to a higher inhibition efficiency. Moreover, the emission of gases was continuously monitored: the Gasmet results revealed that SO2, HCN and NH3 were the most important decomposition products of thiourea. Thiourea is non-toxic, environment-friendly and can be sprayed into the post-combustion zone in form of powder or aqueous solution. The cost of thiourea at least can be partially compensated by its high inhibition efficiency. Therefore, the application of thiourea in a full-scale incinerator system is promising and encouraging. PMID:25481352

  14. Lathyrus cicera copper amine oxidase reactions with tryptamine.

    Science.gov (United States)

    Pietrangeli, Paola; Bellelli, Andrea; Fattibene, Paola; Mondovì, Bruno; Morpurgo, Laura

    2012-04-01

    Lathyrus cicera copper amine oxidase (LCAO) rapidly formed the typical Cu(I)-TPQ semiquinone UV-visible spectrum, identical to that formed by other substrates, upon O(2) exhaustion by turnover with excess tryptamine. A new band at 630 nm formed more slowly, with intensity dependent on aldehyde and H(2)O(2) concentrations. On prolonged incubation, all bands decayed in parallel, together with loss of enzymatic activity. The blue color disappeared on addition of KCN, a Cu(I) stabilizing agent, while the intensity of the radical visible bands increased. This shows that the 630 nm absorbing species is a Cu(II) derivative, as confirmed by the unchanged intensity of the EPR spectrum of the frozen blue solution from that of the native protein. Rapid kinetics experiments showed that this species derives from a reduced form of the protein, plus aldehyde and H(2)O(2) and that it is not in dynamic equilibrium with the radical. Given the similar population of the semiquinone radical with all substrates, it is possible that the reaction with aldehyde and H(2)O(2) occurs in all cases although substrates lacking the indole group only produce the Cu(I)-semiquinone band. The radical participation to the catalytic activity is demonstrated by the observation that its relative population (controlled by the pH) parallels changes in the reoxidation rate constant, while the 630 nm absorbing species is implied in the inactivation process, which depends on H(2)O(2) and aldehyde concentration. The results of the paper are consistent with half-of-the-site reactivity, i.e. the two subunits of LCAO are kinetically and spectroscopically distinct from each other. PMID:22369770

  15. Direct β-C(sp(3))-H Functionalization of Aliphatic Amines to α,β-Unsaturated Imines, Aldehydes, and Chromenes.

    Science.gov (United States)

    Mandal, Sumana; Mahato, Sujit; Jana, Chandan K

    2015-08-01

    A metal-free method for direct β-C(sp(3))-H functionalization of aliphatic amine was developed. The method is based on a reaction that yields enamine directly from the corresponding aliphatic amine, which otherwise requires the aid of metallic reagent and/or external oxidant. The reaction is operationally simple, general, and highly efficient in functionalizing both cyclic and acyclic amines. Structurally diverse unsaturated imines were obtained from N-heterocycles, while acyclic amines provided 2-alkyl cinnamaldehyde and benzopyran derivatives with excellent E/Z-selectivity. PMID:26204435

  16. Important Roles of Enthalpic and Entropic Contributions to CO 2 Capture from Simulated Flue Gas and Ambient Air Using Mesoporous Silica Grafted Amines

    KAUST Repository

    Alkhabbaz, Mustafa A.

    2014-09-24

    © 2014 American Chemical Society. The measurement of isosteric heats of adsorption of silica supported amine materials in the low pressure range (0- 0.1 bar) is critical for understanding the interactions between CO2 and amine sites at low coverage and hence to the development of efficient amine adsorbents for CO2 capture from flue gas and ambient air. Heats of adsorption for an array of silica-supported amine materials are experimentally measured at low coverage using a Calvet calorimeter equipped with a customized dosing manifold. In a series of 3-aminopropylfunctionalized silica materials, higher amine densities resulted in higher isosteric heats of adsorption, clearly showing that the density/proximity of amine sites can influence the amine efficiency of adsorbents. In a series of materials with fixed amine loading but different amine types, strongly basic primary and secondary amine materials are shown to have essentially identical heats of adsorption near 90 kJ/mol. However, the adsorption uptakes vary substantially as a function of CO2 partial pressure for different primary and secondary amines, demonstrating that entropic contributions to adsorption may play a key role in adsorption at secondary amine sites, making adsorption at these sites less effi cient at the low coverages that are important to the direct capture of CO2 from ambient air. Thus, while primary amines are confirmed to be the most effective amine types for CO2 capture from ambient air, this is not due to enhanced enthalpic contributions associated with primary amines over secondary amines, but may be due to unfavorable entropic factors associated with organization of the second alkyl chain on the secondary amine during CO2 adsorption. Given this hypothesis, favorable entropic factors may be the main reason primary amine based adsorbents are more effective under air capture conditions.

  17. Deposition of stable amine coating onto polycaprolactone nanofibers by low pressure cyclopropylamine plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Manakhov, Anton [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Nečas, David [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Čechal, Jan [CEITEC — Central European Institute of Technology, Brno University of Technology, Technická 3058/10, 616 00 Brno (Czech Republic); Pavliňák, David [Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Eliáš, Marek [Plasma Technologies, CEITEC — Central European Institute of Technology, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 2, Brno 61137 (Czech Republic); and others

    2015-04-30

    Amine-rich films are of high interest for the bio-applications including drug delivery and tissue engineering thanks to their high reactivity allowing the formation of the covalent linkages between biomolecules and a surface. However, the bio-applications of amine-rich films require their good stability in water which is often achieved at large expenses of the amine concentration. Recently, non-toxic cyclopropylamine (CPA) has been applied for the plasma polymerization of films bearing high NH{sub x} environment combined with the moderate thickness loss (20%) after water immersion for 48 h. In this work, the amine-rich film with the NH{sub x} concentration over 7 at.% was deposited on Si substrates and polycaprolactone nanofiber meshes by using CPA plasma polymerization (pulsed mode) in a vertically oriented stainless steel reactor. The substrates were placed at the radio frequency electrode and the ion bombardment caused by direct-current self-bias was suppressed by using high pressure of 50 Pa. Analysis of samples by scanning electron microscopy did not reveal any cracks in the deposited layer formed during a sample immersion in water. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed a slight oxidation of amine groups in water but the film still contained 5 at.% of NH{sub x} (according to the N1s XPS fitting) after the immersion. The rapid oxidation of amine groups was observed during the aging experiment carried out in air at room temperature because FTIR revealed an increase of amide peaks that increased progressively with aging time. However, this oxidation was significantly reduced if the plasma polymer was stored at − 20 °C. Since the films exhibit high amine concentration and very good water stability they have great potential for applications as biocompatible functional coatings. - Highlights: • Cyclopropylamine plasma polymers deposited on polycaprolactone nanofibers • Amine-rich films with high

  18. Amine terminated SAMs: Investigating why oxygen is present in these films

    Energy Technology Data Exchange (ETDEWEB)

    Baio, J.E.; Weidner, T.; Brison, J. [National ESCA and Surface Analysis Center for Biomedical Problems, University of Washington, Departments of Bioengineering and Chemical Engineering, Box 351750, Seattle, WA 98195 (United States); Graham, D.J. [Asemblon, 15340 NE 92nd Street, Suite B, Redmond, WA 98052 United States (United States); Gamble, Lara J. [National ESCA and Surface Analysis Center for Biomedical Problems, University of Washington, Departments of Bioengineering and Chemical Engineering, Box 351750, Seattle, WA 98195 (United States)], E-mail: gamble@nb.engr.washington.edu; Castner, David G. [National ESCA and Surface Analysis Center for Biomedical Problems, University of Washington, Departments of Bioengineering and Chemical Engineering, Box 351750, Seattle, WA 98195 (United States)], E-mail: castner@nb.engr.washington.edu

    2009-05-15

    Self-assembled monolayers (SAMs) on gold prepared from amine-terminated alkanethiols have long been employed as model positively charged surfaces. Yet in previous studies significant amounts of unexpected oxygen containing species are always detected in amine terminated SAMs. Thus, the goal of this investigation was to determine the source of these oxygen species and minimize their presence in the SAM. The surface composition, structure, and order of amine-terminated SAMs on Au were characterized by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), sum frequency generation (SFG) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. XPS determined compositions of amine-terminated SAMs in the current study exhibited oxygen concentrations of 2.4 {+-} 0.4 atomic %, a substantially lower amount of oxygen than reported in previously published studies. High-resolution XPS results from the S{sub 2p}, C{sub 1s} and N{sub 1s} regions did not detect any oxidized species. Angle-resolved XPS indicated that the small amount of oxygen detected was located at or near the amine head group. Small amounts of oxidized nitrogen, carbon and sulfur secondary ions, as well as ions attributed to water, were detected in the ToF-SIMS data due to the higher sensitivity of ToF-SIMS. The lack of N-O, S-O, and C-O stretches in the SFG spectra are consistent with the XPS and ToF-SIMS results and together show that oxidation of the amine-terminated thiols alone can only account for, at most, a small fraction of the oxygen detected by XPS. Both the SFG and angle-dependent NEXAFS indicated the presence of gauche defects in the amine SAMs. However, the SFG spectral features near 2865 cm{sup -1}, assigned to the stretch of the methylene group next to the terminal amine unit, demonstrate the SAM is reasonably ordered. The SFG results also show another broad feature near 3200 cm{sup -1} related to hydrogen-bonded water. From this multi

  19. Rapid simultaneous determination of amines and organic acids in citrus using high-performance liquid chromatography.

    Science.gov (United States)

    Uckoo, Ram M; Jayaprakasha, Guddadarangavvanahally K; Nelson, Shad D; Patil, Bhimanagouda S

    2011-01-15

    Rapid analytical method for the simultaneous separation and determination of amines and organic acids is a vital interest for quality control of citrus and their products. In the present study, a simultaneous high performance liquid chromatography (HPLC) method for the rapid separation of three amines and two organic acids was developed. Chromatographic separation of compounds was achieved using Xbridge C(18) column at ambient temperature, with an isocratic mobile phase of 3mM phosphoric acid at a flow rate of 1.0 mL min(-1). A photodiode array (PDA) detector was used to monitor the eluent at 223 nm and 254 nm with a total analysis time of 10 min. Extraction of amines and organic acids from citrus juice was optimized. The method was validated by tests of linearity, recovery, precision and ruggedness. The limit of detection (LOD) and limit of quantification (LOQ) for amines and ascorbic acid were determined to be 5 ng and 9.8 ng, respectively. All calibration curves showed good linearity (R(2) ≥ 0.9999) within the test ranges. The recoveries of the amines and organic acids ranged between 84% and 117%. The identity of each peak was confirmed by mass spectral (MS) analysis. The developed method was successfully applied to analyze the content of amines and organic acids in six different species and two varieties of citrus. Results indicate that mandarin and Marrs sweet orange contain high level of amines, while pummelo and Rio Red grapefruit had high content of ascorbic acid (137-251 μg mL(-1)) and citric acid (5-22 mg mL(-1)). Synephrine was the major amine present in Clementine (114 μg mL(-1)) and Marrs sweet orange (85 μg mL(-1)). To the best of our knowledge, this is the first report on simultaneous separation and quantification of amines and organic acids in Marrs sweet orange, Meyer lemon, Nova tangerine, Clementine, Ugli tangelo and Wekiwa tangelo. PMID:21147342

  20. Amine terminated SAMs: Investigating why oxygen is present in these films

    International Nuclear Information System (INIS)

    Self-assembled monolayers (SAMs) on gold prepared from amine-terminated alkanethiols have long been employed as model positively charged surfaces. Yet in previous studies significant amounts of unexpected oxygen containing species are always detected in amine terminated SAMs. Thus, the goal of this investigation was to determine the source of these oxygen species and minimize their presence in the SAM. The surface composition, structure, and order of amine-terminated SAMs on Au were characterized by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), sum frequency generation (SFG) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. XPS determined compositions of amine-terminated SAMs in the current study exhibited oxygen concentrations of 2.4 ± 0.4 atomic %, a substantially lower amount of oxygen than reported in previously published studies. High-resolution XPS results from the S2p, C1s and N1s regions did not detect any oxidized species. Angle-resolved XPS indicated that the small amount of oxygen detected was located at or near the amine head group. Small amounts of oxidized nitrogen, carbon and sulfur secondary ions, as well as ions attributed to water, were detected in the ToF-SIMS data due to the higher sensitivity of ToF-SIMS. The lack of N-O, S-O, and C-O stretches in the SFG spectra are consistent with the XPS and ToF-SIMS results and together show that oxidation of the amine-terminated thiols alone can only account for, at most, a small fraction of the oxygen detected by XPS. Both the SFG and angle-dependent NEXAFS indicated the presence of gauche defects in the amine SAMs. However, the SFG spectral features near 2865 cm-1, assigned to the stretch of the methylene group next to the terminal amine unit, demonstrate the SAM is reasonably ordered. The SFG results also show another broad feature near 3200 cm-1 related to hydrogen-bonded water. From this multi-technique investigation it is clear

  1. Adsorption of formaldehyde vapor by amine-functionalized mesoporous silica materials

    Institute of Scientific and Technical Information of China (English)

    SRISUDA Saeung; VIROTE Boonamnuayvitaya

    2008-01-01

    The amine-functionalized mesoporous silica materials were prepared via the co-condensation reaction of tetraethoxysilane and three types of organoalkoxysilanes:3-aminopropyl-trimethoxysilane,n-(2-aminoethyl)-3-aminopropyltrimethoxysilane,and 3-(2-(2-aminoehtylamino)ethylamino) propyl-trimethoxysilane.Cetyltrimethylammonium bromide was used as a template for forming pores.Specific surface area and pore volume of the amine-functionalized mesoporous silica materials were determined using surface area and pore size analyzer.Fourier transform infrared (FTIR) spectroscope was employed for identifying the functional groups on pore surface.In addition,the amine-functionalized mesoporous silica materials were applied as adsorbents for adsorbing formaldehyde vapor.FTIR spectra showed the evidence of the reaction between formaldehyde molecules and amine groups on pore surface of adsorbents.The equilibrium data of formaldehyde adsorbed on the adsorbents were analyzed using the Langmuir,Freundiich and Temkin isotherm.The sample functionalized from n-(2-aminoethyl)-3-aminopropyltrimethoxysilane showed the highest adsorption capacity owing to its amine groups and the large pore diameter.

  2. Inhibitory Effects of Spices on Biogenic Amine Accumulation during Fish Sauce Fermentation.

    Science.gov (United States)

    Zhou, Xuxia; Qiu, Mengting; Zhao, Dandan; Lu, Fei; Ding, Yuting

    2016-04-01

    The presence of high levels of biogenic amines is detrimental to the quality and safety of fish sauce. This study investigated the effects of ethanol extracts of spices, including garlic, ginger, cinnamon, and star anise extracts, in reducing the accumulation of biogenic amines during fish sauce fermentation. The concentrations of biogenic amines, which include histamine, putrescine, tyramine, and spermidine, all increased during fish sauce fermentation. When compared with the samples without spices, the garlic and star anise extracts significantly reduced these increases. The greatest inhibitory effect was observed for the garlic ethanolic extracts. When compared with controls, the histamine, putrescine, tyramine, and spermidine contents and the overall biogenic amine levels of the garlic extract-treated samples were reduced by 30.49%, 17.65%, 26.03%, 37.20%, and 27.17%, respectively. The garlic, cinnamon, and star anise extracts showed significant inhibitory effects on aerobic bacteria counts. Furthermore, the garlic and star anise extracts showed antimicrobial activity against amine producers. These findings may be helpful for enhancing the safety of fish sauce. PMID:26953496

  3. Gradient Elution Method for Successive Separation of Common Cations and Hydrophobic Amines using Suppressed Ion Chromatography

    International Nuclear Information System (INIS)

    In mixed waste the separation and sequential determination of alkali, alkaline earth metals mixed with hydrophobic amines represent a challenge analytical problem. The effect of a new mobile phase (amido-sulfonic acid, ASA) on the suppressed ion chromatographic separation of alkali, alkaline earth metals and hydrophobic amines on Dionex Ion Pac CS12A analytical column was investigated. The addition of surface modifier to the eluent appears to provide better interfacial compatibility between the mobile and stationary phase and facilitates the rapid equilibration of analytes. Incorporation of a very low concentration of the additive may also alters the stationary phase surface by creating a fine-tuning and improves the partition characteristics of the analytes. A dramatic and sufficient elution capability of ASA for sequential separation of the analytes was found and rational mechanisms for the separated analytes are proposed. ASA can act as ion-pairing agent resulting in the separation of a wide variety of amines. The new mobile phase (ASA) is proved to have more successful separation over methanesulfonic acid (MSA) even with eluent free solvent. The proposed method shows that a profound particular effect on the separation of aliphatic diamine (ethylenediamine) and organic amine (cyclohexylamine) was achieved in addition to all common cations and amines using isocratic elution of 18 mM of ASA without organic eluent modifier

  4. Biogenic amines determination in some traditional cheeses in West Azerbaijan province of Iran.

    Science.gov (United States)

    Razavi Rohani, Seyed Mehdi; Aliakbarlu, Javad; Ehsani, Ali; Hassanzadazar, Hassan

    2013-01-01

    Biogenic amines (BA) are nitrogenous compounds that possess biological activity. The source of production is the microbial decarboxylation of amino acids. This compounds are found in various types of cheese. The aim of this work was to evaluate the BA content of some traditional cheeses in West Azerbaijan province Iran. For this purpose, 70 samples of Koopeh, 10 samples of Lighvan and 5 samples of Red Salmas cheeses were obtained from local supermarkets of different cities of West Azerbaijan province. After preparation of samples, biogenic amines content was evaluated by modified HPLC method. The presence of histamine, cadaverine, putrescine and tyramine in tested cheeses were observed. Total amount of biogenic amines was highest in Red Salmas cheese with 1426.91 ppm. It followed by Lighvan cheese and Koopeh cheese with 1008.98 and 517.71 ppm, respectively. Putrescine, cadaverine, histamine and tyramine were detected in Koopeh cheese at levels up to 156.09, 282.34, 70.80, 8.48 ppm respectively. These amines were detected also in Lighvan cheese at levels up to 277.53, 342.74, 37.58, 351.12 ppm and in Red Salmas cheese samples at levels up to 438.03, 701.05, 105.21, 182.62 ppm, respectively. Large amounts of biogenic amines can indicate non hygienic conditions and contamination of used milk for cheese production. PMID:25653782

  5. Serum amine oxidase activity contributes to crisis in mouse embryo cell lines.

    Science.gov (United States)

    Parchment, R E; Lewellyn, A; Swartzendruber, D; Pierce, G B

    1990-06-01

    This paper reports the results of experiments to test the hypothesis that crisis of spontaneous transformation is caused by the hydrogen peroxide and/or aldehydes generated from endogenous polyamines by serum amine oxidase [amine: oxygen oxidoreductase (deaminating), EC 1.4.3.6]. After 4-5 weeks of culture, crisis occurred in 16 of 29 cell lines derived from limb buds of embryos from SJL/J, C3H, and CD-1 mice. In contrast, after the same time in culture but in medium supplemented with aminoguanidine, which inhibits serum amine oxidase, crisis occurred in only 1 of 41 cell lines. Protection against crisis was maximal in cell lines of SJL/J embryos, in which the incidence of crisis fell from 7 of 9 in untreated controls of 0 to 12 in the presence of 2 mM aminoguanidine. 2-Mercaptoethanol at 150-300 microM, which protects cells from serum amine oxidase-dependent polyamine toxicity, also protected the cell lines against crisis. These protected cell lines retained proliferative potential, diploid DNA content, and the mixture of cell types found in the primary cultures. These results indicate that cytotoxic catabolites generated by serum amine oxidase caused at least a large portion, but perhaps not all, of the cellular damage that leads to crisis in mouse embryo cell lines. PMID:2349241

  6. Cocaine affects foraging behaviour and biogenic amine modulated behavioural reflexes in honey bees

    Directory of Open Access Journals (Sweden)

    Eirik Søvik

    2014-11-01

    Full Text Available In humans and other mammals, drugs of abuse alter the function of biogenic amine pathways in the brain leading to the subjective experience of reward and euphoria. Biogenic amine pathways are involved in reward processing across diverse animal phyla, however whether cocaine acts on these neurochemical pathways to cause similar rewarding behavioural effects in animal phyla other than mammals is unclear. Previously, it has been shown that bees are more likely to dance (a signal of perceived reward when returning from a sucrose feeder after cocaine treatment. Here we examined more broadly whether cocaine altered reward-related behaviour, and biogenic amine modulated behavioural responses in bees. Bees developed a preference for locations at which they received cocaine, and when foraging at low quality sucrose feeders increase their foraging rate in response to cocaine treatment. Cocaine also increased reflexive proboscis extension to sucrose, and sting extension to electric shock. Both of these simple reflexes are modulated by biogenic amines. This shows that systemic cocaine treatment alters behavioural responses that are modulated by biogenic amines in insects. Since insect reward responses involve both octopamine and dopamine signalling, we conclude that cocaine treatment altered diverse reward-related aspects of behaviour in bees. We discuss the implications of these results for understanding the ecology of cocaine as a plant defence compound. Our findings further validate the honey bee as a model system for understanding the behavioural impacts of cocaine, and potentially other drugs of abuse.

  7. Bifunctional (cyclopentadienone)iron-tricarbonyl complexes: Synthesis, computational studies and application in reductive amination

    KAUST Repository

    Moulin, Solenne

    2013-11-15

    Reductive amination under hydrogen pressure is a valuable process in organic chemistry to access amine derivatives from aldehydes or ketones. Knölker\\'s complex has been shown to be an efficient iron catalyst in this reaction. To determine the influence of the substituents on the cyclopentadienone ancillary ligand, a series of modified Knölker\\'s complexes was synthesised and fully characterised. These complexes were also transformed into their analogous acetonitrile iron-dicarbonyl complexes. Catalytic activities of these complexes were evaluated and compared in a model reaction. The scope of this reaction is also reported. For mechanistic insights, deuterium-labelling experiments and DFT calculations were undertaken and are also presented. Festival of amination: Two series of modified Knölker\\'s complexes were synthesised and applied in the reductive amination of various carbonyl derivatives with primary or secondary amines (see scheme, TIPS = triisopropylsilyl). For a mechanistic insight, deuterium-labelling experiments and DFT calculations were undertaken and are also presented. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Biogenic amines determination in some traditional cheeses in West Azerbaijan province of Iran

    Directory of Open Access Journals (Sweden)

    Seyed Mehdi Razavi Rohani

    2013-06-01

    Full Text Available Biogenic amines (BA are nitrogenous compounds that possess biological activity. The source of production is the microbial decarboxylation of amino acids. This compounds are found in various types of cheese. The aim of this work was to evaluate the BA content of some traditional cheeses in West Azerbaijan province Iran. For this purpose, 70 samples of Koopeh, 10 samples of Lighvan and 5 samples of Red Salmas cheeses were obtained from local supermarkets of different cities of West Azerbaijan province. After preparation of samples, biogenic amines content was evaluated by modified HPLC method. The presence of histamine, cadaverine, putrescine and tyramine in tested cheeses were observed. Total amount of biogenic amines was highest in Red Salmas cheese with 1426.91 ppm. It followed by Lighvan cheese and Koopeh cheese with 1008.98 and 517.71 ppm, respectively. Putrescine, cadaverine, histamine and tyramine were detected in Koopeh cheese at levels up to 156.09, 282.34, 70.80, 8.48 ppm respectively. These amines were detected also in Lighvan cheese at levels up to 277.53, 342.74, 37.58, 351.12 ppm and in Red Salmas cheese samples at levels up to 438.03, 701.05, 105.21, 182.62 ppm, respectively. Large amounts of biogenic amines can indicate non hygienic conditions and contamination of used milk for cheese production.

  9. Safety assessment of the biogenic amines in fermented soya beans and fermented bean curd.

    Science.gov (United States)

    Yang, Juan; Ding, Xiaowen; Qin, Yingrui; Zeng, Yitao

    2014-08-01

    To evaluate the safety of biogenic amines, high performance liquid chromatography (HPLC) was used to evaluate the levels of biogenic amines in fermented soya beans and fermented bean curd. In fermented soya beans, the total biogenic amines content was in a relatively safe range in many samples, although the concentration of histamine, tyramine, and β-phenethylamine was high enough in some samples to cause a possible safety threat, and 8 of the 30 samples were deemed unsafe. In fermented bean curd, the total biogenic amines content was more than 900 mg/kg in 19 white sufu amples, a level that has been determined to pose a safety hazard; putrescine was the only one detected in all samples and also had the highest concentration, which made samples a safety hazard; the content of tryptamine, β-phenethylamine, tyramine, and histamine had reached the level of threat to human health in some white and green sufu samples, and that may imply another potential safety risk; and 25 of the 33 samples were unsafe. In conclusion, the content of biogenic amines in all fermented soya bean products should be studied and appropriate limits determined to ensure the safety of eating these foods. PMID:25029555

  10. Advanced Development and Characterization of DEA Amine-Polysulfone/Polyvinylacetate Blend Membranes

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-09-01

    Full Text Available Membrane technology effectively separates CO2 from CH4 and has been practiced for many years but requires membranes with high selectivity and permeability. Different approaches are employed to improve membrane performance and it is soon possible to develop a blended polymeric membrane that separates high pressure gas streams at the point of processing pressure. However, glassy polymers suffer a lack of permeability causing their performance to drop as an upper bound trade-off but highly selective and rubbery polymers have high permeability with low selectivity. As an amine solution is capable of purifying naturally acidic gas, blending glassy, rubbery polymers with amines-specifically, polysulfone and polyvinyl acetate with diethanol amine in dimethyl acetamide as solvent-we developed flat sheet membranes with desirable properties. As it is now possible to acquire amine-polymer blends with more desirable properties by mixing with a miscible polymer, it is essential to observe factors that affect the polymer's miscibility with amines. Hence, we also analyzed the effects of blend ratios on different properties. Blended membranes of different ratios were synthesized and their functional groups were characterized by Fourier Transformed Infra-Red spectroscopy (FTIR. We then employed Thermal Gravimetric Analysis (TGA to describe weight loss and Field Emission Scanning Electron Microscopy (FESEM to determine respective morphologies.

  11. The kinetics and mechanism of the organo-iridium catalysed racemisation of amines.

    Science.gov (United States)

    Stirling, Matthew J; Mwansa, Joseph M; Sweeney, Gemma; Blacker, A John; Page, Michael I

    2016-08-01

    The dimeric iodo-iridium complex [IrCp*I2]2 (Cp* = pentamethylcyclopentadiene) is an efficient catalyst for the racemisation of secondary and tertiary amines at ambient and higher temperatures with a low catalyst loading. The racemisation occurs with pseudo-first-order kinetics and the corresponding four rate constants were obtained by monitoring the time dependence of the concentrations of the (R) and (S) enantiomers starting with either pure (R) or (S) and show a first-order dependence on catalyst concentration. Low temperature (1)H NMR data is consistent with the formation of a 1 : 1 complex with the amine coordinated to the iridium and with both iodide anions still bound to the metal-ion, but at the higher temperatures used for kinetic studies binding is weak and so no saturation zero-order kinetics are observed. A cross-over experiment with isotopically labelled amines demonstrates the intermediate formation of an imine which can dissociate from the iridium complex. Replacing the iodides in the catalyst by other ligands or having an amide substituent in Cp* results in a much less effective catalysts for the racemisation of amines. The rate constants for a deuterated amine yield a significant primary kinetic isotope effect kH/kD = 3.24 indicating that hydride transfer is involved in the rate-limiting step. PMID:27377259

  12. Proposed chemical mechanisms leading to secondary organic aerosol in the reactions of aliphatic amines with hydroxyl and nitrate radicals

    Science.gov (United States)

    Price, Derek J.; Clark, Christopher H.; Tang, Xiaochen; Cocker, David R.; Purvis-Roberts, Kathleen L.; Silva, Philip J.

    2014-10-01

    The presence and importance of amines in the atmosphere, including aliphatic amines, continues to gain more attention. The atmospheric reaction mechanisms of these amines with key atmospheric radicals are important to predict both daytime and nighttime atmospheric chemistry. While previous studies have focused on the production of amine salts, this analysis looks at the importance of peroxy radical reactions to the formation of secondary organic aerosol. Atmospheric oxidation mechanisms are presented to explain the observed chemistry. A series of environmental chamber experiments were conducted in which aliphatic tertiary and secondary amines were reacted with either hydroxyl radical (OH) or nitrate radical (NO3). Chemical composition of the aerosol products was obtained with a High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and a Particle Into Liquid Sampler Time of Flight Mass Spectrometer (PILS-ToF-MS), while the chemical composition of the gas-phase products was obtained with a Selected Ion Flow Tube Mass Spectrometer (SIFT-MS). A number of aerosol-phase mass spectra showed highly oxidized fragments at a much higher molecular weight (MW) than the amine precursor. It is proposed that these larger compounds are oligomers formed through peroxy radical reactions with hydrogen rearrangement. Another reaction pathway observed was the formation of amine salts. The relative importance of each pathway to the overall production of aerosol is found to be dependent on the type of amine and oxidant. For example, the oligomers were observed in the tertiary methyl amines, while the formation of amine salts was more prevalent in the secondary and tertiary ethyl amines.

  13. Efficient acetylation of primary amines and amino acids in environmentally benign brine solution using acetyl chloride

    Indian Academy of Sciences (India)

    Kaushik Basu; Suchandra Chakraborty; Achintya Kumar Sarkar; Chandan Saha

    2013-05-01

    Acetyl chloride is one of the most commonly available and cheap acylating agent but its high reactivity and concomitant instability in water precludes its use to carry out acetylation in aqueous medium. The present methodology illustrates the efficient acetylation of primary amines and amino acids in brine solution by means of acetyl chloride under weakly basic condition in the presence of sodium acetate and/or triethyl amine followed by trituration with aqueous saturated bicarbonate solution. This effort represents the first efficient use of this most reactive but cheap acetylating agent to acetylate amines in excellent yields in aqueous medium. This is a potentially useful green chemical transformation where reaction takes place in environment-friendly brine solution leading to easy work-up and isolation of the amide derivatives. Mechanistic rationale of this methodology is also important.

  14. Diamond surface functionalization with biomimicry – Amine surface tether and thiol moiety for electrochemical sensors

    Energy Technology Data Exchange (ETDEWEB)

    Sund, James B., E-mail: jim@jamessund.com [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Causey, Corey P. [Departments of Chemistry and Biochemistry, Duke University, Durham, NC (United States); Wolter, Scott D. [Department of Physics, Elon University, Elon, NC 27244 (United States); Parker, Charles B., E-mail: charles.parker@duke.edu [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Stoner, Brian R. [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Research Triangle Institute (RTI) International, Research Triangle Park, NC (United States); Toone, Eric J. [Departments of Chemistry and Biochemistry, Duke University, Durham, NC (United States); Glass, Jeffrey T. [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States)

    2014-05-01

    Highlights: • Diamond surfaces were functionalized with organic molecules using a novel approach. • Used biomimicry to select a molecule to bind NO, similar to the human body. • Molecular orbital theory predicted the molecule-analyte oxidation behavior. • A thiol moiety was attached to an amine surface tether on the diamond surface. • XPS analysis verified each surface functionalization step. - Abstract: The surface of conducting diamond was functionalized with a terminal thiol group that is capable of binding and detecting nitrogen–oxygen species. The functionalization process employed multiple steps starting with doped diamond films grown by plasma enhanced chemical vapor deposition followed by hydrogen termination and photochemical attachment of a chemically protected amine alkene. The surface tether was deprotected to reveal the amine functionality, which enabled the tether to be extended with surface chemistry to add a terminal thiol moiety for electrochemical sensing applications. Each step of the process was validated using X-ray photoelectron spectroscopy analysis.

  15. Diamond surface functionalization with biomimicry – Amine surface tether and thiol moiety for electrochemical sensors

    International Nuclear Information System (INIS)

    Highlights: • Diamond surfaces were functionalized with organic molecules using a novel approach. • Used biomimicry to select a molecule to bind NO, similar to the human body. • Molecular orbital theory predicted the molecule-analyte oxidation behavior. • A thiol moiety was attached to an amine surface tether on the diamond surface. • XPS analysis verified each surface functionalization step. - Abstract: The surface of conducting diamond was functionalized with a terminal thiol group that is capable of binding and detecting nitrogen–oxygen species. The functionalization process employed multiple steps starting with doped diamond films grown by plasma enhanced chemical vapor deposition followed by hydrogen termination and photochemical attachment of a chemically protected amine alkene. The surface tether was deprotected to reveal the amine functionality, which enabled the tether to be extended with surface chemistry to add a terminal thiol moiety for electrochemical sensing applications. Each step of the process was validated using X-ray photoelectron spectroscopy analysis

  16. Supported Gold Nanoparticles for Efficient α-Oxygenation of Secondary and Tertiary Amines into Amides.

    Science.gov (United States)

    Jin, Xiongjie; Kataoka, Kengo; Yatabe, Takafumi; Yamaguchi, Kazuya; Mizuno, Noritaka

    2016-06-13

    Although the α-oxygenation of amines is a highly attractive method for the synthesis of amides, efficient catalysts suited to a wide range of secondary and tertiary alkyl amines using O2 as the terminal oxidant have no precedent. This report describes a novel, green α-oxygenation of a wide range of linear and cyclic secondary and tertiary amines mediated by gold nanoparticles supported on alumina (Au/Al2 O3 ). The observed catalysis was truly heterogeneous, and the catalyst could be reused. The present α-oxygenation utilizes O2 as the terminal oxidant and water as the oxygen atom source of amides. The method generates water as the only theoretical by-product, which highlights the environmentally benign nature of the present reaction. Additionally, the present α-oxygenation provides a convenient method for the synthesis of (18) O-labeled amides using H2 (18) O as the oxygen source. PMID:27151621

  17. Origins of stereoselectivity in intramolecular aldol reactions catalyzed by cinchona amines.

    Science.gov (United States)

    Lam, Yu-Hong; Houk, K N

    2015-02-11

    The intramolecular aldol condensation of 4-substituted heptane-2,6-diones leads to chiral cyclohexenones. The origins of the enantioselectivities of this reaction, disclosed by List et al. using a cinchona alkaloid-derived primary amine (cinchona amine) organocatalyst, have been determined with dispersion-corrected density functional theory (DFT). The stereocontrol hinges on the chair preference of the substrate-enamine intermediate and the conformational preferences of a hydrogen-bonded nine-membered aldol transition state containing eight heavy atoms. The conformations of the hydrogen-bonded ring in the various stereoisomeric transition structures have been analyzed in detail and shown to closely resemble the conformers of cyclooctane. A model of stereoselectivity is proposed for the cinchona amine catalysis of this reaction. The inclusion of Grimme's dispersion corrections in the DFT calculations (B3LYP-D3(BJ)) substantially improves the agreement of the computed energetics and experiment, attesting to the importance of dispersion effects in stereoselectivity. PMID:25629689

  18. High production volume chemical Amine Oxide [C8-C20] category environmental risk assessment

    DEFF Research Database (Denmark)

    Sanderson, Hans; Tibazarwa, Caritas; Greggs, William;

    2009-01-01

    personal care products. Given the lack of persistence or bioaccumulation, and the low likelihood of these chemicals partitioning to soil, the focus of the environmental assessment is on the aquatic environment. In the United States, the E-FAST model is used to estimate effluent concentrations in the United......An environmental assessment of amine oxides has been conducted under the OECD SIDS High Production Volume (HPV) Program via the Global International Council of Chemical Associations (ICCA) Amine Oxides Consortium. Amine oxides are primarily used in conjunction with surfactants in cleaning and...... States from manufacturing facilities and from municipal facilities resulting from consumer product uses. Reasonable worst-case ratios of predicted environmental concentration (PEC) to predicted no effect concentration (PNEC) range from 0.04 to 0.003, demonstrating that these chemicals are a low risk to...

  19. Low-temperature microchip nonaqueous capillary electrophoresis of aliphatic primary amines: applications to Titan chemistry.

    Science.gov (United States)

    Cable, Morgan L; Stockton, Amanda M; Mora, Maria F; Willis, Peter A

    2013-01-15

    We demonstrate microchip nonaqueous capillary electrophoresis (μNACE) analysis of primary aliphatic amines (C1-C18) in ethanol down to -20 °C as a first step in adapting microfluidic protocols for in situ analysis on Titan. To our knowledge, this is the first report of a nonaqueous separation at -20 °C on-chip. Limits of detection (LODs) ranged from 1.0 nM to 2.6 nM, and we identified several primary amines ranging in length from C2 to C16 in Titan aerosol analogue (tholin) samples; new amines were also detected in a tholin sample exposed to oxygen and liquid water. This preliminary work validates the sensitivity and efficacy of microfluidic chemical analysis of complex organics with relevance to Titan aerosols and surface deposits. PMID:23214444

  20. The role of brain biogenic amines in the control of pituitary-adrenocortical activity

    Science.gov (United States)

    Maickel, R. P.

    1975-01-01

    It was found that pretreatment of animals with desmethyl imipramine antagonized the reserpine-induced sedation without preventing the decline in brain amines or the hypersecretion of adrenocorticotropic hormone (ACTH). The antagonism of reserpine-induced ACTH hypersecretion by the monoamine oxidose (MAO) inhibitor pargyline (MO 911, N-methyl-N-benzyl-2-propynylamine) was studied. Evidence is presented that this antagonism is related to the level of brain biogenic amines maintained during the course of action of the drug. Pretreatment with MAO inhibitors does not affect the ACTH hypersecretion evoked by exposure to cold or chlorpromazine, lending further support to the hypothesis that reserpine-induced ACTH hypersecretion is related to brain amine changes.

  1. Magnetic particles-based biosensor for biogenic amines using an optical oxygen sensor as a transducer

    International Nuclear Information System (INIS)

    We have developed a fibre optic biosensor with incorporated magnetic microparticles for the determination of biogenic amines. The enzyme diamine oxidase from Pisum sativum was immobilized either on chitosan-coated magnetic microparticles or on commercial microbeads modified with a ferrofluid. Both the immobilized enzyme and the ruthenium complex were incorporated into a UV-cured inorganic-organic polymer composite and deposited on a lens that was connected, by optical fibres, to an electro-optical detector. The enzyme catalyzes the oxidation of amines under consumption of oxygen. The latter was determined by measuring the quenched fluorescence lifetime of the ruthenium complex. The limits of detection for the biogenic amines putrescine and cadaverine are 25-30 μmol L-1, and responses are linear up to a concentration of 1 mmol L-1. (author)

  2. Effect of gamma irradiation on the activity of some microorganisms producing biogenic amines in some foods

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on the proximate chemical composition ( moisture content , protein , fat, ash) chemical freshness tests (TBA, TVB-N, TMA, FAN, ph) and microbiological changes (total bacterial count, proteolytic bacteria, Enterobacteriaceae, moulds and yeasts counts) occurred in sardine fish and pastirma during cold storage at (4 ± 1 degree C) were fully investigated. Furthermore, the bacterial activity causing the formation of biogenic amines were also studied. In addition, the determination of biogenic amines in sardine fish and pastirma produced by these bacteria were explored. The effects of irradiation doses (1, 3 and 5 kGy) which were applied as a trial to reduce biogenic amines formation in sardine fish and pastirma were also investigated. In addition, the effect of the tested irradiation doses (1, 3 and 5 kGy) on organoleptic properties of the treated sardine fish and pastirma were determined.

  3. Simultaneous determination of selected biogenic amines in alcoholic beverage samples by isotachophoretic and chromatographic methods.

    Science.gov (United States)

    Jastrzębska, Aneta; Piasta, Anna; Szłyk, Edward

    2014-01-01

    A simple and useful method for the determination of biogenic amines in beverage samples based on isotachophoretic separation is described. The proposed procedure permitted simultaneous analysis of histamine, tyramine, cadaverine, putrescine, tryptamine, 2-phenylethylamine, spermine and spermidine. The data presented demonstrate the utility, simplicity, flexibility, sensitivity and environmentally friendly character of the proposed method. The precision of the method expressed as coefficient of variations varied from 0.1% to 5.9% for beverage samples, whereas recoveries varied from 91% to 101%. The results for the determination of biogenic amines were compared with an HPLC procedure based on a pre-column derivatisation reaction of biogenic amines with dansyl chloride. Furthermore, the derivatisation procedure was optimised by verification of concentration and pH of the buffer, the addition of organic solvents, reaction time and temperature. PMID:24350674

  4. Highly efficient heterogeneous procedure for the conjugate addition of amines to electron deficient alkenes

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The novel efficient procedure has been developed for the conjugate addition of amines to electron deficient alkenes. K2CO3 supported on different carriers have been synthesized for the conjugate addition of amines and alkenes. After optimizing the reaction conditions, K2CO3/MgO was chosen as the most efficient catalyst for the reactions. The results showed that the catalyst was very efficient for the conjugate addition of amines to electron deficient alkenes with the excellent yields in several minutes. Operational simplicity, without need of any solvent, low cost of the catalyst used, high yields, reusability, excellent chemoselectivity, and applicability to large-scale reactions are the key features of this methodology.

  5. “COLATURA DI ALICI “ CETARESE: EVALUATION OF AMINIC PROFILE

    Directory of Open Access Journals (Sweden)

    A Anastasio

    2008-12-01

    Full Text Available “Colatura d’alici”is a speciality made in Cetara, a clear ,amber-coloured liquid that has sharp taste, prepared with the juice coming from the anchovy salting process. The anchovies are caught in the Gulf of Salerno between the mounths of March and July. The colatura is ready at the beginning of December. Histamine poisoning, a food-borne chemical intoxication caused by the consumption of food containing toxic levels of histamine, is a syndrome commonly associated with the consumption of seafood beloging to the Engraulidae and some fish families. Histamine and biogenic amine levels were determined in “colatura di alici di Cetara”. The amine was separated in a HPLC/FL system. Histamine level were lower than the law limits only in one of the examinated products. A reduction of the histamine and amine levels in colatura cetarese can be obtained using a determinate salt concentrations and changing way of seasoning.

  6. Chemoenzymatic dynamic kinetic resolution of primary amines using a recyclable palladium nanoparticle catalyst together with lipases.

    Science.gov (United States)

    Gustafson, Karl P J; Lihammar, Richard; Verho, Oscar; Engström, Karin; Bäckvall, Jan-E

    2014-05-01

    A catalyst consisting of palladium nanoparticles supported on amino-functionalized siliceous mesocellular foam (Pd-AmP-MCF) was used in chemoenzymatic dynamic kinetic resolution (DKR) to convert primary amines to amides in high yields and excellent ee's. The efficiency of the nanocatalyst at temperatures below 70 °C enables reaction conditions that are more suitable for enzymes. In the present study, this is exemplified by subjecting 1-phenylethylamine (1a) and analogous benzylic amines to DKR reactions using two commercially available lipases, Novozyme-435 (Candida antartica Lipase B) and Amano Lipase PS-C1 (lipase from Burkholderia cepacia) as biocatalysts. The latter enzyme has not previously been used in the DKR of amines because of its low stability at temperatures over 60 °C. The viability of the heterogeneous Pd-AmP-MCF was further demonstrated in a recycling study, which shows that the catalyst can be reused up to five times. PMID:24724828

  7. A water-gated organic thin film transistor as a sensor for water-borne amines.

    Science.gov (United States)

    Algarni, Saud A; Althagafi, Talal M; Naim, Abdullah Al; Grell, Martin

    2016-06-01

    The p-type semiconducting polymer Poly(2,5-bis(3-hexadecylthiophen-2-yl)thieno[3,2-b]thiophene) (PBTTT) displays innate sensitivity to water-borne amines. We demonstrate this with the help of water-gated PBTTT thin film transistors (TFTs). When octylamine is added to the gating water, TFTs respond with a significantly reduced saturated drain current. Underlying TFT drift is minimised by initial conditioning, and remaining drift can be accounted for by normalising current response to the current level under purge immediately before exposure. Normalised current response vs. amine concentration is reproducible between different transistors, and can be modelled by a Langmuir surface adsorption isotherm, which suggests physisorption of analyte at the PBTTT surface, rather than bulk penetration. Same PBTTT transistors do not respond to 1- octanol, confirming the specific affinity between amines and thiophene- based organic semiconductors. PMID:27130096

  8. Excess molar enthalpies for binary mixtures of different amines with water

    International Nuclear Information System (INIS)

    Highlights: • Isothermal excess molar enthalpies for binary mixtures of different amines with water. • The Redlich–Kister equation and the NRTL model was used to fit the experimental data. • The excess molar enthalpies were discussed with different structures of amines. - Abstract: The isothermal excess molar enthalpies for binary mixtures of different amines with water were measured with a C-80 Setaram calorimeter. The experimental results indicate that the excess molar enthalpy is related to the molecular structure. The experimental excess molar enthalpies were satisfactorily fitted with the Redlich–Kister equation. They were also used to test the suitability of the NRTL model, and the deviations are a little larger than the R–K equation

  9. Conformational distortion of α-phenylethyl amine in cryogenic matrices - a matrix isolation VCD study.

    Science.gov (United States)

    Pollok, Corina H; Merten, Christian

    2016-05-21

    The chiral amine α-phenylethyl amine (PEA) was isolated in cryogenic matrices and investigated using vibrational circular dichroism (VCD) and infrared spectroscopy. The potential energy surface (PES) of PEA features five different conformers connected by relatively low conformational transition states. Based on the IR spectra, it could be confirmed that all conformational energy barriers are passed at a deposition temperature of 20 K, and that only the global minimum conformation of PEA is populated in both argon and nitrogen matrices. However, differences in the calculated and experimental VCD spectra indicate deviations from the minimum structure by perturbation of the phenyl ring as well as of the amine orientation. The degree of the perturbation is found to also depend on the choice of the host gas, which shows the subtle influence of the environment on the conformational distortion of PEA. PMID:27125494

  10. Mechanism of Oxidative Amidation of Nitroalkanes with Oxygen and Amine Nucleophiles by Using Electrophilic Iodine.

    Science.gov (United States)

    Li, Jing; Lear, Martin J; Kwon, Eunsang; Hayashi, Yujiro

    2016-04-11

    Recently, we developed a direct method to oxidatively convert primary nitroalkanes into amides that entailed mixing an iodonium source with an amine, base, and oxygen. Herein, we systematically investigated the mechanism and likely intermediates of such methods. We conclude that an amine-iodonium complex first forms through N-halogen bonding. This complex reacts with aci-nitronates to give both α-iodo- and α,α-diiodonitroalkanes, which can act as alternative sources of electrophilic iodine and also generate an extra equimolar amount of I(+) under O2. In particular, evidence supports α,α-diiodonitroalkane intermediates reacting with molecular oxygen to form a peroxy adduct; alternatively, these tetrahedral intermediates rearrange anaerobically to form a cleavable nitrite ester. In either case, activated esters are proposed to form that eventually reacts with nucleophilic amines in a traditional fashion. PMID:26938791

  11. Preparation of aminated-polyacrylonitrile nanofiber membranes for the adsorption of metal ions: Comparison with microfibers

    International Nuclear Information System (INIS)

    Polyacrylonitrile nanofibers (PAN-nFs) were produced using the electrospinning method. Subsequently, the electrospun fibers were modified by diethylenetriamine to produce aminated polyacrylonitrile (APAN) nanofibers. Finally, the adsorbability of copper ions on the surface of the nanofibers was examined in an aqueous solution. Attenuated total internal reflection (ATIR) analysis confirmed the surface amination of the produced PAN-nFs. The grafting yield was calculated by the gravimetric method. The optimum condition was determined to yield the maximum grafting of amine groups to PAN with no losses in sample flexibility. Atomic absorption spectroscopy (AAS) was used to measure the copper ion concentration in the solution. Results indicate that the adsorption process in nanofibers is three times faster in comparison with microfibers. Moreover, the pH effect was studied based on the adsorption behavior of copper ions on the APAN nanofibers. In addition, thermodynamic parameters were calculated, revealing that the process was endothermic and demonstrating that randomness increased at the solid-solution interface during the process. The obtained enthalpy value indicates that the chelation of copper ions among the aminated polyacrylonitrile can be regarded as a chemical adsorption process. The adsorption data fit well with the Langmuir isotherm. The saturation adsorption capacity obtained from the Langmuir model for Cu(II) ions was 116.522 mg/g which is five times more than the reported value for APAN microfibers [S. Deng, R. Bai, J.P. Chen, Aminated polyacrylonitrile fibers for lead and copper removal, Langmuir,19 (2003)5058-5064]. Analysis using atomic force microscopy (AFM) showed that the surface roughness increased upon adsorption of the metal ion. Scanning electron microscopy (SEM) examination demonstrated that there were no cracks or sign of degradation on the surface after amination.

  12. Amine functionalized graphene oxide/CNT nanocomposite for ultrasensitive electrochemical detection of trinitrotoluene

    Energy Technology Data Exchange (ETDEWEB)

    Sablok, Kavita; Bhalla, Vijayender; Sharma, Priyanka; Kaushal, Roohi; Chaudhary, Shilpa [Institute of Microbial Technology (CSIR) Sector-39A, Chandigarh160036 (India); Suri, C. Raman, E-mail: raman@imtech.res.in [Institute of Microbial Technology (CSIR) Sector-39A, Chandigarh160036 (India)

    2013-03-15

    Highlights: ► Binding of electron-deficient trinitrotoluene to the electron rich amino groups to form JM complexes. ► rGO/CNT based platform for enhanced electrochemical detection. ► Functionalization and characterization of rGO/CNT with amine derivative. ► Ultrasenstitive and specific detection of TNT. -- Abstract: Binding of electron-deficient trinitrotoluene (TNT) to the electron rich amine groups on a substrate form specific charge-transfer Jackson–Meisenheimer (JM) complex. In the present work, we report formation of specific JM complex on amine functionalized reduced graphene oxide/carbon nanotubes- (a-rGO/CNT) nanocomposite leading to sensitive detection of TNT. The CNT were dispersed using graphene oxide that provides excellent dispersion by attaching to CNT through its hydrophobic domains and solubilizes through the available -OH and -COOH groups on screen printed electrode (SPE). The GO was reduced electrochemically to form reduced graphene that remarkably increases electrochemical properties owing to the intercalation of high aspect CNT on graphene flakes as shown by TEM micrograph. The surface amine functionalization of dropcasted and rGO/CNT was carried out using a bi-functional cross linker ethylenediamine. The extent of amine functionalization on modified electrodes was confirmed using energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and confocal microscopy. The FTIR and Raman spectra further suggested the formation of JM complex between amine functionalized electrodes and TNT leading to a shift in peak intensity together with peak broadening. The a-rGO/CNT nanocomposite prepared electrode surface leads to ultra-trace detection of TNT upto 0.01 ppb with good reproducibility (n = 3). The a-rGO/CNT sensing platform could be an alternate for sensitive detection of TNT explosive for various security and environmental applications.

  13. Molecular Evolution and Functional Divergence of Trace Amine-Associated Receptors.

    Science.gov (United States)

    Eyun, Seong-Il; Moriyama, Hideaki; Hoffmann, Federico G; Moriyama, Etsuko N

    2016-01-01

    Trace amine-associated receptors (TAARs) are a member of the G-protein-coupled receptor superfamily and are known to be expressed in olfactory sensory neurons. A limited number of molecular evolutionary studies have been done for TAARs so far. To elucidate how lineage-specific evolution contributed to their functional divergence, we examined 30 metazoan genomes. In total, 493 TAAR gene candidates (including 84 pseudogenes) were identified from 26 vertebrate genomes. TAARs were not identified from non-vertebrate genomes. An ancestral-type TAAR-like gene appeared to have emerged in lamprey. We found four therian-specific TAAR subfamilies (one eutherian-specific and three metatherian-specific) in addition to previously known nine subfamilies. Many species-specific TAAR gene duplications and losses contributed to a large variation of TAAR gene numbers among mammals, ranging from 0 in dolphin to 26 in flying fox. TAARs are classified into two groups based on binding preferences for primary or tertiary amines as well as their sequence similarities. Primary amine-detecting TAARs (TAAR1-4) have emerged earlier, generally have single-copy orthologs (very few duplication or loss), and have evolved under strong functional constraints. In contrast, tertiary amine-detecting TAARs (TAAR5-9) have emerged more recently and the majority of them experienced higher rates of gene duplications. Protein members that belong to the tertiary amine-detecting TAAR group also showed the patterns of positive selection especially in the area surrounding the ligand-binding pocket, which could have affected ligand-binding activities and specificities. Expansions of the tertiary amine-detecting TAAR gene family may have played important roles in terrestrial adaptations of therian mammals. Molecular evolution of the TAAR gene family appears to be governed by a complex, species-specific, interplay between environmental and evolutionary factors. PMID:26963722

  14. Adducts of Amine with Dimeric Rhodium(II) Tetracarboxylates - Formation of Nitrogenous Chiral Center

    International Nuclear Information System (INIS)

    Rhodium(II) tetracarboksylates Rh2(RCO2)4 (1a) are able to produce various complexes with organic ligands, like the 1:1 and 2:1 adducts containing axially bonded ligands (1b), or the compounds with rearranged dirhodium core (1c). The solution of dirhodium(II) tetracarboxylate and a ligand usually contains a mixture of adducts, due to ligand exchange and different equilibriums between species. However, application of nuclear magnetic resonance measurements at reduced temperature allows often observing the signals of all species in the solution. Ligands containing nitrogen atom were the subject of our previous investigation. It was found that dirhodium salts are able to form both 1:1 and 2:1 adducts with an amine, depending on reagents ratio. The present investigations are devoted to the amines with general formula NRR'R', is the amines having potential nitrogenous chiral center. An amine with three various substituents NRR'R' is formally a chiral molecule, but in the solution the molecule forms racemic mixture due to fast pyramidal inversion at the nitrogen atom. However, dirhodium(II) tetracarboxylates bonding the amine acts as an agent freezing pyramidal inversion at nitrogen atom, and results in formation of a new, nitrogenous chiral center in the adduct. Thus, the chiral dirhodium salt (4R)-Rh2[(CF3)(OCH3)(Ph)CO2]4 forms with benzyl-ethyl-methylamine five adducts: (4R)/(S), (4R)/(R) (1:1 adducts) and (R)/(4R)/(R), (R)/(4R)/(S), (S)/(4R)/(S) (2:1 adducts). All these diastereoisomers were detected by means of low temperature NMR (253 K). Similar effect was observed for the adducts with methyl-(1-phenylethyl)- amine, PhCH(NHCH3)CH3, having both nitrogenous and carbon chiral centers. (author)

  15. Molecular Evolution and Functional Divergence of Trace Amine-Associated Receptors.

    Directory of Open Access Journals (Sweden)

    Seong-Il Eyun

    Full Text Available Trace amine-associated receptors (TAARs are a member of the G-protein-coupled receptor superfamily and are known to be expressed in olfactory sensory neurons. A limited number of molecular evolutionary studies have been done for TAARs so far. To elucidate how lineage-specific evolution contributed to their functional divergence, we examined 30 metazoan genomes. In total, 493 TAAR gene candidates (including 84 pseudogenes were identified from 26 vertebrate genomes. TAARs were not identified from non-vertebrate genomes. An ancestral-type TAAR-like gene appeared to have emerged in lamprey. We found four therian-specific TAAR subfamilies (one eutherian-specific and three metatherian-specific in addition to previously known nine subfamilies. Many species-specific TAAR gene duplications and losses contributed to a large variation of TAAR gene numbers among mammals, ranging from 0 in dolphin to 26 in flying fox. TAARs are classified into two groups based on binding preferences for primary or tertiary amines as well as their sequence similarities. Primary amine-detecting TAARs (TAAR1-4 have emerged earlier, generally have single-copy orthologs (very few duplication or loss, and have evolved under strong functional constraints. In contrast, tertiary amine-detecting TAARs (TAAR5-9 have emerged more recently and the majority of them experienced higher rates of gene duplications. Protein members that belong to the tertiary amine-detecting TAAR group also showed the patterns of positive selection especially in the area surrounding the ligand-binding pocket, which could have affected ligand-binding activities and specificities. Expansions of the tertiary amine-detecting TAAR gene family may have played important roles in terrestrial adaptations of therian mammals. Molecular evolution of the TAAR gene family appears to be governed by a complex, species-specific, interplay between environmental and evolutionary factors.

  16. The Effects of Amine-Carboxyborane Related Derivatives on UMR-106 Bone Metabolism

    OpenAIRE

    Murphy, Margaret E.; Elkins, Amy L.; Shrewsbury, Robert P.; Sood, Anup; Spielvogel, Bernard F.; Hall, Iris H.

    1996-01-01

    The amine-carboxyboranes and related derivatives have been shown to be potent anti-inflammatory and anti-osteoporosis agents. Their action in part appears to be mediated by the modulation of cytokines, e.g. TNFα or IL-1. Previous studies have demonstrated that LPS induced macrophages release of TNFα maximally at 60 to 90 min. and IL-1 from 5 to 8 hr. The amine-carboxyboranes reduced significantly the release of these cytokines but also blocked TNFα high affinity binding to UMR-106 receptor at...

  17. Combined heterogeneous metal/chiral amine: multiple relay catalysis for versatile eco-friendly synthesis.

    Science.gov (United States)

    Deiana, Luca; Jiang, Yan; Palo-Nieto, Carlos; Afewerki, Samson; Incerti-Pradillos, Celia A; Verho, Oscar; Tai, Cheuk-Wai; Johnston, Eric V; Córdova, Armando

    2014-03-24

    Herein is described a versatile and broad synergistic strategy for expansion of chemical space and the synthesis of valuable molecules (e.g. carbocycles and heterocycles), with up to three quaternary stereocenters, in a highly enantioselective fashion from simple alcohols (31 examples, 95:5 to >99.5:0.5 e.r.) using integrated heterogeneous metal/chiral amine multiple relay catalysis and air/O₂ as the terminal oxidant. A novel highly 1,4-selective heterogeneous metal/amine co-catalyzed hydrogenation of enals was also added to the relay catalysis sequences. PMID:24677482

  18. Amine-Oxide Hybrid Materials for CO2 Capture from Ambient Air.

    Science.gov (United States)

    Didas, Stephanie A; Choi, Sunho; Chaikittisilp, Watcharop; Jones, Christopher W

    2015-10-20

    Oxide supports functionalized with amine moieties have been used for decades as catalysts and chromatographic media. Owing to the recognized impact of atmospheric CO2 on global climate change, the study of the use of amine-oxide hybrid materials as CO2 sorbents has exploded in the past decade. While the majority of the work has concerned separation of CO2 from dilute mixtures such as flue gas from coal-fired power plants, it has been recognized by us and others that such supported amine materials are also perhaps uniquely suited to extract CO2 from ultradilute gas mixtures, such as ambient air. As unique, low temperature chemisorbents, they can operate under ambient conditions, spontaneously extracting CO2 from ambient air, while being regenerated under mild conditions using heat or the combination of heat and vacuum. This Account describes the evolution of our activities on the design of amine-functionalized silica materials for catalysis to the design, characterization, and utilization of these materials in CO2 separations. New materials developed in our laboratory, such as hyperbranched aminosilica materials, and previously known amine-oxide hybrid compositions, have been extensively studied for CO2 extraction from simulated ambient air (400 ppm of CO2). The role of amine type and structure (molecular, polymeric), support type and structure, the stability of the various compositions under simulated operating conditions, and the nature of the adsorbed CO2 have been investigated in detail. The requirements for an effective, practical air capture process have been outlined and the ability of amine-oxide hybrid materials to meet these needs has been discussed. Ultimately, the practicality of such a "direct air capture" process is predicated not only on the physicochemical properties of the sorbent, but also how the sorbent operates in a practical process that offers a scalable gas-solid contacting strategy. In this regard, the utility of low pressure drop monolith

  19. Diamond surface functionalization with biomimicry - Amine surface tether and thiol moiety for electrochemical sensors

    Science.gov (United States)

    Sund, James B.; Causey, Corey P.; Wolter, Scott D.; Parker, Charles B.; Stoner, Brian R.; Toone, Eric J.; Glass, Jeffrey T.

    2014-05-01

    The surface of conducting diamond was functionalized with a terminal thiol group that is capable of binding and detecting nitrogen-oxygen species. The functionalization process employed multiple steps starting with doped diamond films grown by plasma enhanced chemical vapor deposition followed by hydrogen termination and photochemical attachment of a chemically protected amine alkene. The surface tether was deprotected to reveal the amine functionality, which enabled the tether to be extended with surface chemistry to add a terminal thiol moiety for electrochemical sensing applications. Each step of the process was validated using X-ray photoelectron spectroscopy analysis.

  20. Mesoporous Niobium Oxide Spheres as an Effective Catalyst for the Transamidation of Primary Amides with Amines

    KAUST Repository

    Ghosh, Subhash Chandra

    2014-02-06

    Mesoporous niobium oxide spheres (MNOS), conveniently prepared by a novel antisolvent precipitation approach, have been shown to be an effective catalyst for the transamidation of primary amides with amines. This novel transamidation can be efficiently carried out under solvent-free conditions and is applicable to a wide range of primary amides and amines to provide N-alkyl amides in good to excellent yields. The catalyst is highly stable and reusable. The application of this transamidation reaction has been demonstrated in the synthesis of antidepressant drug moclobemide and other druglike compounds. © 2014 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.

  1. Direct amination of benzene to aniline with several typical vanadium complexes

    Institute of Scientific and Technical Information of China (English)

    Yu Fen Lv; Liang Fang Zhu; Qiu Yuan Liu; Bin Guo; Xiao Ke Hu; Chang Wei Hu

    2009-01-01

    The liquid-phase direct catalytic amination of benzene to aniline was performed in acetic acid water solvent using a series of vanadium(Ⅲ,Ⅳ,Ⅴ)complexes with N,O-or O,O-ligands as catalysts and hydroxylamine hydrochloride as the aminating agent.The vanadium complexes exhibited much higher selectivity towards the production of aniline than NaVO3 or VOSO4.Under the optimized conditions,an aniline yield of 42.5% and a TON of 48 with a high selectivity of above 99.9% was obtained using 0.2 mmol of[VO(OAc)2]as the catalyst.

  2. Bioactive amines in Brazilian wines: types, levels and correlation with physico-chemical parameters

    OpenAIRE

    Solange C. Souza; Karine H. Theodoro; Élson R. Souza; Silvana da Motta; Maria Beatriz Abreu Glória

    2005-01-01

    The levels of ten bioactive amines and the physico-chemical characteristics of Cabernet Sauvignon, Cabernet Franc and Merlot wines from Bento Gonçalves, RS, Brazil, vintage of 1999 were investigated. The physico-chemical characteristics varied significantly: pH from 3.80 to 4.07, total acidity from 67.7 to 85.3 meq/L, alcohol content from 11.45 to 12.46 mL/100 mL and total SO2 from 9.6 to 102 mg/L. Six amines were detected in every sample - spermidine, putrescine, histamine, tyramine, seroton...

  3. Serum amine oxidase activity contributes to crisis in mouse embryo cell lines.

    OpenAIRE

    Parchment, R E; Lewellyn, A; Swartzendruber, D.; Pierce, G. B.

    1990-01-01

    This paper reports the results of experiments to test the hypothesis that crisis of spontaneous transformation is caused by the hydrogen peroxide and/or aldehydes generated from endogenous polyamines by serum amine oxidase [amine: oxygen oxidoreductase (deaminating), EC 1.4.3.6]. After 4-5 weeks of culture, crisis occurred in 16 of 29 cell lines derived from limb buds of embryos from SJL/J, C3H, and CD-1 mice. In contrast, after the same time in culture but in medium supplemented with aminogu...

  4. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    Science.gov (United States)

    Smith, R.E.; Dolbeare, F.A.

    1980-10-21

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 4-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes. No Drawings

  5. Genetically modified CHO cells for studying the genotoxicity of heterocyclic amines from cooked foods

    International Nuclear Information System (INIS)

    We have developed metabolically competent CHO cells to evaluate the genotoxicity associated with heterocyclic amines, such as those that are present in cooked foods. Into repair-deficient UV5 cells we introduced cDNAs for expressing cytochrome P450IA2 and acetyltransferases. We then genetically reverted these transformed lines to obtain matched metabolically competent repair-deficient/proficient lines. For a high mutagenic response, we find a requirement for acetyltransferase with IQ but not with PhIP. This system allows for both quantifying mutagenesis and analyzing the mutational spectra produced by heterocyclic amines

  6. Excretion of metabolites of biogenic amines in patients with irradiated brain tumours

    International Nuclear Information System (INIS)

    The metabolites of biogenic amines were determined in the 24-hour urine samples of patients submitted to surgical removal of a malignant brain tumour and subsequently to telecobalt therapy of the corresponding head region. A significant increase in the excretion of 5-hydroxyindoleasetic acid (5-HIAA), vanillinmandelic acid (VMA) as well as of free 3-methoxy-4-hydroxy-phenylglycol (MHPG) during the period of irradiation was found. This increase is presumably the result of radiation induced release of their parent amines from the brain; in the case of VMA the secondary response of the peripheral sympathetic system might occur. (author)

  7. Evaluation of N-nitrosopiperidine formation from biogenic amines during the production of dry fermented sausages

    OpenAIRE

    De Mey, Eveline; De Maere, Hannelore; Goemaere, Olivier; Steen, Liselot; Peeters, Christine; Derdelinckx, Guy; Paelinck, Hubert; Fraeye, Ilse

    2014-01-01

    The aim of this study was to determine the role of the precursors cadaverine and piperidine in the N-nitrosopiperidine (NPIP) formation during the production of dry fermented sausages. The influences of pH (4.9 and 5.3), sodium nitrite (0 and 150 mg/kg) and ascorbate (0 and 500 mg/kg) were investigated by the use of a dry fermented sausage model. The biogenic amines and volatile N-nitrosamines were analyzed by HPLC-UV and GC-TEA. The major biogenic amines were tyramine (TYR), putrescine (PUT)...

  8. Formation and Human Risk of Carcinogenic Heterocyclic Amines Formed from Natural Precursors in Meat

    Energy Technology Data Exchange (ETDEWEB)

    Knize, M G; Felton, J S

    2004-11-22

    A group of heterocyclic amines that are mutagens and rodent carcinogens form when meat is cooked to medium and well-done states. The precursors of these compounds are natural meat components: creatinine, amino acids and sugars. Defined model systems of dry-heated precursors mimic the amounts and proportions of heterocyclic amines found in meat. Results from model systems and cooking experiments suggest ways to reduce their formation and, thus, to reduce human intake. Human cancer epidemiology studies related to consumption of well-done meat products are listed and compared.

  9. Synthesis of New N-Arylpyrimidin-2-amine Derivatives Using a Palladium Catalyst

    Directory of Open Access Journals (Sweden)

    So Ha Lee

    2008-04-01

    Full Text Available New N-aryl-4-(pyridin-3-ylpyrimidin-2-amine derivatives were synthesizedfrom the corresponding amines, applying optimized Buchwald-Hartwig aminationconditions using dichlorobis(triphenylphosphinePd(II, xantphos and sodium tertbutoxidein refluxing toluene under a nitrogen atmosphere. The target N-aryl derivativeswere obtained in moderate to good yields ranging from 27% to 82%. The proceduredescribed could be widely employed for the preparation of new heterocyclic compounds.The structures of the new compounds were confirmed by FT-NMR, FT-IR and elementalanalysis.

  10. Analysis of primary aromatic amines (PAA) in black nylon kitchenware 2014

    DEFF Research Database (Denmark)

    Trier, Xenia; Granby, Kit

    Primary aromatic amines (PAA) are chemical compounds, of which some are carcinogenic and allergenic, while others of these compounds are suspected carcinogens. PAA may arise in materials intended for food contact as a result of the occurrence of impurities or degradation products of e.g. aromatic...... isocyanates used in lacquers and adhesives in azocolourants. According to the regulation on plastics EC 10/2011: ‘Plastic materials and articles shall not release primary aromatic amines, excluding those appearing in Table 1 of Annex I, in a detectable quantity into food or food simulant. The detection limit...

  11. Long-Range Ruthenium-Amine Electronic Communication through the para-Oligophenylene Wire

    OpenAIRE

    Jun-Jian Shen; Yu-Wu Zhong

    2015-01-01

    The studies of long-range electronic communication are hampered by solubility and potential-splitting issues. A “hybridized redox-asymmetry” method using a combination of organic and inorganic redox species is proposed and exemplified to overcome these two issues. Complexes 1(PF6)–6(PF6) (from short to long in length) with the organic redox-active amine and inorganic cyclometalated ruthenium termini bridged by the para-oligophenylene wire have been prepared. Complex 6 has the longest Ru-amine...

  12. Biogenic amine content, histamine-forming bacteria, and adulteration of pork in tuna sausage products.

    Science.gov (United States)

    Kung, Hsien-Feng; Tsai, Yung-Hsiang; Chang, Shih-Chih; Hong, Tang-Yao

    2012-10-01

    Twenty-five tuna sausage products were purchased from retail markets in Taiwan. The rates of occurrence of biogenic amines, histamine-forming bacteria, and adulteration by pork and poultry were determined. The average content of various biogenic amines in all tested samples was less than 2.0 mg/100 g (Thunnus albacares for 22 samples (88%), Thunnus alalunga for 1 sample (4%), and Thunnus thynnus for 1 sample (4%), whereas the remaining sample was identified as Makaira nigricans (blue marlin). PMID:23043830

  13. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    Science.gov (United States)

    Smith, Robert E.; Dolbeare, Frank A.

    1979-01-01

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 5-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes.

  14. A Cell-Penetrating Peptide with a Guanidinylethyl Amine Structure Directed to Gene Delivery

    Science.gov (United States)

    Oba, Makoto; Kato, Takuma; Furukawa, Kaori; Tanaka, Masakazu

    2016-01-01

    A peptide composed of lysine with a guanidinylethyl (GEt) amine structure in the side chain [Lys(GEt)] was developed as a cell-penetrating peptide directed to plasmid DNA (pDNA) delivery. The GEt amine adopted a diprotonated form at neutral pH, which may have led to the more efficient cellular uptake of a Lys(GEt)-peptide than an arginine-peptide at a low concentration. Lys(GEt)-peptide/pDNA complexes showed the highest transfection efficiency due to efficient endosomal escape without any cytotoxicity. Lys(GEt)-peptide may be a promising candidate as a gene delivery carrier.

  15. Seasonal variation of aliphatic amines in marine sub-micrometer particles at the Cape Verde islands

    Directory of Open Access Journals (Sweden)

    H. Herrmann

    2009-12-01

    Full Text Available Monomethylamine (MA, dimethylamine (DMA and diethylamine (DEA were detected at non-negligible concentrations in sub-micrometer particles at the Cap Verde Atmospheric Observatory (CVAO located on the island of São Vicente in Cape Verde during algal blooms in 2007. The concentrations of these amines in five stage impactor samples ranged from 0–30 pg m−3 for MA, 130–360 pg m−3 for DMA and 5–110 pg m−3 for DEA during the spring bloom in May 2007 and 2–520 pg m−3 for MA, 100–1400 pg m−3 for DMA and 90–760 pg m−3 for DEA during an unexpected winter algal bloom in December 2007. Anomalously high Saharan dust deposition and intensive ocean layer deepening were found at the Atmospheric Observatory and the associated Ocean Observatory during algal bloom periods. The highest amine concentrations in fine particles (impactor stage 2, 0.14–0.42 μm indicate that amines are likely taken up from the gas phase into the acidic sub-micrometer particles. The contribution of amines to the organic carbon (OC content ranged from 0.2–2.5% C in the winter months, indicating the importance of this class of compounds to the carbon cycle in the marine environment. Furthermore, aliphatic amines originating from marine biological sources likely contribute significantly to the nitrogen content in the marine atmosphere. The average contribution of the amines to the detected nitrogen species in sub-micrometer particles can be non-negligible, especially in the winter months (0.1% N–1.5% N in the sum of nitrate, ammonium and amines. This indicates that these smaller aliphatic amines can be important for the carbon and the nitrogen cycles in the remote marine environment.

  16. Improved Parameterization of Amine-Carboxyate and Amine-Phosphate Interactions for Molecular Dynamics Simulations Using the CHARMM and AMBER Force Fields

    CERN Document Server

    Yoo, Jejoong

    2015-01-01

    Over the past decades, molecular dynamics (MD) simulations of biomolecules have become a mainstream biophysics technique. As the length and time scales amenable to the MD method increase, shortcomings of the empirical force fields---which have been developed and validated using relatively short simulations of small molecules---become apparent. One common artifact is aggregation of water-soluble biomolecules driven by artificially strong charge--charge interactions. Here, we report a systematic refinement of Lennard-Jones parameters (NBFIX) describing amine--carboxylate and amine--phosphate interactions, which brings MD simulations of basic peptide-mediated nucleic acids assemblies and lipid bilayer membranes in better agreement with experiment. As our refinement neither affects the existing parameterization of bonded interaction nor does it alter the solvation free energies, it improves realism of an MD simulation without introducing additional artifacts.

  17. Thieme Chemistry Journal Awardees - Where are They Now? Catalytic Transport with an Amine Carrier in a Fluorous Triphasic Reaction

    OpenAIRE

    Montanari, Vittorio; Yu, Marvin S.; Curran, Dennis P.

    2009-01-01

    Several aromatic aldehydes are transported by a fluorous amine from one organic phase through a fluorous phase to another organic phase. The derived imines react with phenylhydrazine to immobilize the transported product as a hydrazone and release the amine for reuse. In this way, catalytic transport is accomplished for the first time.

  18. AN EFFICIENT AND CHEMOSELECTIVE CBZ-PROTECTION OF AMINES USING SILICA-SULFURIC ACID AT ROOM TEMPERATURE

    Science.gov (United States)

    A simple, facile, and chemoselective N-benzyloxycarbonylation of amines using silica-sulfuric acid that proceeds under solvent-free conditions at room temperature has been achieved. These reactions are applicable to a wide variety of primary (aliphatic, cyclic) secondary amines, ...

  19. 40 CFR 721.9220 - Reaction products of secondary alkyl amines with a substituted benzenesulfonic acid and sulfuric...

    Science.gov (United States)

    2010-07-01

    ... amines with a substituted benzenesulfonic acid and sulfuric acid (generic name). 721.9220 Section 721... Reaction products of secondary alkyl amines with a substituted benzenesulfonic acid and sulfuric acid... benzenesulfonic acid and sulfuric acid (PMNs P-89-703, P-89-755, and P-89-756) are subject to reporting under...

  20. Kinetic Study on Aminolysis of 4-Nitrophenyl Isonicotinate in Acetonitrile: Effect of Amine Basicity on Reactivity and Reaction Mechanism

    International Nuclear Information System (INIS)

    A kinetic study is reported on nucleophilic substitution reactions of 4-nitrophenyl isonicotinate with a series of cyclic secondary amines in MeCN. The plots of kobsd vs. [amine] curve upward for the reactions with weakly basic amines (e. g., morpholine, 1-(2-hydroxyethyl)piperazine, and piperazine) but are linear for those with strongly basic amines (e. g., piperidine and 3-methylpiperidine). The curved plots for the reactions with the weakly basic amines are typical for reactions reported previously to proceed through uncatalyzed and catalyzed routes with two intermediates (e. g., a zwitterionic tetrahedral intermediate T± and its deprotonated form T-). In contrast, the linear plots for the reactions with the strongly basic amines indicate that the catalytic route (i. e., the deprotonation process to yield T- from T± by a second amine molecule) is absent. The Brφnsted-type plots for Kk2 and Kk3 (i. e., the rate constants for the uncatalyzed and catalyzed routes, respectively) exhibit excellent linear correlations with βnuc = 0.99 and 0.69, respectively. The effect of amine basicity on the reaction mechanism is discussed in detail

  1. Formation and destruction of biogenic amines in Chunjang (a black soybean paste) and Jajang (a black soybean sauce).

    Science.gov (United States)

    Bai, Xuezhi; Byun, Bo Young; Mah, Jae-Hyung

    2013-11-15

    Chunjang and Jajang samples were analysed for biogenic amine contents by using HPLC equipped with a UV-Vis detector. Chunjang samples contained relatively large amounts of histamine (up to 273mg/kg) and tyramine (up to 131mg/kg), whereas Jajang samples had relatively small amounts of biogenic amines (mostly less than 40mg/kg). There appeared to be a strong relationship between biogenic amine contents in Chunjang and Jajang, and the biogenic amines in Chunjang were found to be pyrolysed during frying thereof to prepare Jajang. Meanwhile, the total plate counts of Chunjang samples ranged from 5 to 8logcfu/g, and most strains that were isolated from Chunjang samples were identified to be Bacillus subtilis (91.0%). The strains isolated from a sample in which relatively small amounts of biogenic amines were detected showed significantly weak abilities to produce biogenic amines. This indicates that biogenic amine contents in Chunjang are primarily attributed to bacterial abilities to produce biogenic amines. PMID:23790882

  2. MICROWAVE-ASSISTED CHEMISTRY: SYNTHESIS OF AMINES AND HETEROCYCLES VIA CARBON-NITROGEN BOND FORMATION IN AQUEOUS MEDIA

    Science.gov (United States)

    Improved C-N bond formation under MW influence is demonstrated by a) solventless three-component coupling reaction to generate propargyl amines that uses only Cu (I); b) aqueous N-alkylation of amines by alkyl halides that proceeds expeditiously in the presence of NaOH to deliver...

  3. Palladium-catalyzed aryl amination-heck cyclization cascade: A one-flask approach to 3-substituted Indoles

    DEFF Research Database (Denmark)

    Jensen, Thomas; Pedersen, Henrik; Bang-Andersen, B.;

    2008-01-01

    Two for the price of one: A Pd/dppf-based catalyst provides access to the title compounds from 1,2-dihalogenated aromatic compounds and allylic amines in a single reaction flask. The initial aryl amination step occurs with excellent selectivity for the aryl iodide to ensure the formation of a sin...

  4. Characterization of the in vitro binding and inhibition kinetics of primary amine oxidase/vascular adhesion protein-1 by glucosamine.

    LENUS (Irish Health Repository)

    Olivieri, Aldo

    2012-04-01

    Primary-amine oxidase (PrAO) catalyzes the oxidative deamination of endogenous and exogenous primary amines and also functions, in some tissues, as an inflammation-inducible endothelial factor, known as vascular adhesion protein-1. VAP-1 mediates the slow rolling and adhesion of lymphocytes to endothelial cells in a number of inflammatory conditions, including inflammation of the synovium.

  5. Biogenic amines content in Spanish and French natural ciders: Application of qPCR for quantitative detection of biogenic amine-producers

    OpenAIRE

    Ladero Losada, Víctor Manuel; Coton, M.; Fernández García, María; Burón, Nicolás; Martín, M. Cruz; Guichard, Hugues; Coton, E.; Álvarez González, Miguel Ángel

    2011-01-01

    Biogenic amines (BA) are low molecular weight nitrogenous bases commonly found in fermented foods and beverages and their consumption can induce undesirable reactions. In this work, the BA content in natural cider from Spain and France was determined. Samples from commercially available cider or obtained during the elaboration process were analyzed. A different profile and BA concentration was observed depending on cider origin. qPCR tools developed for the quantitative detection of BA produc...

  6. Validation of an HPLC Analytical Method for Determination of Biogenic Amines in Agricultural Products and Monitoring of Biogenic Amines in Korean Fermented Agricultural Products

    OpenAIRE

    Yoon, Hyeock; Park, Jung Hyuck; Choi, Ari; Hwang, Han-Joon; Mah, Jae-Hyung

    2015-01-01

    An HPLC analytical method was validated for the quantitative determination of biogenic amines in agricultural products. Four agricultural foods, including apple juice, Juk, corn oil and peanut butter, were selected as food matrices based on their water and fat contents (i.e., non-fatty liquid, non-fatty solid, fatty liquid and fatty solid, respectively). The precision, accuracy, recovery, limit of detection (LOD) and quantification (LOQ) were determined to test the validity of an HPLC procedu...

  7. Determination of biogenic amines in squid and white prawn by high-performance liquid chromatography with postcolumn derivatization.

    Science.gov (United States)

    Zhao, Qing-Xi; Xu, Jie; Xue, Chang-Hu; Sheng, Wen-Jing; Gao, Rui-Chang; Xue, Yong; Li, Zhao-Jie

    2007-04-18

    A simple method was developed for the determination of biogenic amines in aquatic food products using a reverse-phase high-performance liquid chromatography with postcolumn automatic o-phthalaldehyde derivatization and fluorescence detection. The linearity, repeatability, and recovery of the method for seven amines (tyramine, putrescine, cadaverine, histamine, agmatine, spermidine, and spermine) were evaluated. This optimized method was applied to detect biogenic amines in squid and white prawn during refrigerated storage. Sensory analysis, pH value, and total volatile base nitrogen value were combined to evaluate the freshness quality of these two raw materials. Agmatine and cadaverine in squid, cadaverine, and putrescine in white prawn were the most obviously changed amines during the storage at two different temperatures, and these biogenic amines could be the effective quality indicators for the freshness of the raw aquatic materials. PMID:17381105

  8. Simultaneous amination of TiO2 nanoparticles in the gas phase synthesis for bio-medical applications

    International Nuclear Information System (INIS)

    A simultaneous synthesis and surface amination method to effectively modify the surface of inorganic nanoparticles is discussed in this study. As a target material system and surface functional group, TiO2 nanoparticles and amine were selected. APTES (3-aminopropyltriethoxysilane), the source of amine group, was mixed with TTIP (titanium tetraisopropoxide) and used for the synthesis of aminated TiO2 nanoparticles. XRD (X-ray diffractometry) results showed TiO2 nanoparticles of pure anatase phase, 15 nm in crystallite size, were successfully synthesized at 700deg. C and 50 mbar. Fourier transformation infrared (FT-IR) spectroscopy measurement and confocal microscopy study using fluoresceine isothiocyanate (FITC) confirmed that amine groups were successfully deposited and activated on the surface of TiO2 nanoparticles.

  9. Simultaneous amination of TiO{sub 2} nanoparticles in the gas phase synthesis for bio-medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyoung-No; Lee, Jai-Sung [Department of Metallurgy and Materials Science, Hanyang University-ERICA, Ansan 426-791 (Korea, Republic of); Kim, Yangeon; Lee, Chang-Woo, E-mail: jslee@hanyang.ac.kr [Battelle-Korea Laboratory, International Center for Converging Technology (Rm401) Korea University, Seoul 136-713 (Korea, Republic of)

    2011-10-29

    A simultaneous synthesis and surface amination method to effectively modify the surface of inorganic nanoparticles is discussed in this study. As a target material system and surface functional group, TiO{sub 2} nanoparticles and amine were selected. APTES (3-aminopropyltriethoxysilane), the source of amine group, was mixed with TTIP (titanium tetraisopropoxide) and used for the synthesis of aminated TiO{sub 2} nanoparticles. XRD (X-ray diffractometry) results showed TiO{sub 2} nanoparticles of pure anatase phase, 15 nm in crystallite size, were successfully synthesized at 700deg. C and 50 mbar. Fourier transformation infrared (FT-IR) spectroscopy measurement and confocal microscopy study using fluoresceine isothiocyanate (FITC) confirmed that amine groups were successfully deposited and activated on the surface of TiO{sub 2} nanoparticles.

  10. Simultaneous amination of TiO2 nanoparticles in the gas phase synthesis for bio-medical applications

    Science.gov (United States)

    Lee, Kyoung-No; Kim, Yangeon; Lee, Chang-Woo; Lee, Jai-Sung

    2011-10-01

    A simultaneous synthesis and surface amination method to effectively modify the surface of inorganic nanoparticles is discussed in this study. As a target material system and surface functional group, TiO2 nanoparticles and amine were selected. APTES (3-aminopropyltriethoxysilane), the source of amine group, was mixed with TTIP (titanium tetraisopropoxide) and used for the synthesis of aminated TiO2 nanoparticles. XRD (X-ray diffractometry) results showed TiO2 nanoparticles of pure anatase phase, 15 nm in crystallite size, were successfully synthesized at 700°C and 50 mbar. Fourier transformation infrared (FT-IR) spectroscopy measurement and confocal microscopy study using fluoresceine isothiocyanate (FITC) confirmed that amine groups were successfully deposited and activated on the surface of TiO2 nanoparticles.

  11. Strong, low-density nanocomposites by chemical vapor deposition and polymerization of cyanoacrylates on aminated silica aerogels.

    Science.gov (United States)

    Boday, Dylan J; Stover, Robert J; Muriithi, Beatrice; Keller, Michael W; Wertz, Jason T; Defriend Obrey, Kimberly A; Loy, Douglas A

    2009-07-01

    Strong polymer-silica aerogel composites were prepared by chemical vapor deposition of cyanoacrylate monomers onto amine-modified aerogels. Amine-modified silica aerogels were prepared by copolymerizing small amounts of (aminopropyl)triethoxysilane with tetraethoxysilane. After silation of the aminated gels with hexamethyldisilazane, they were dried as aerogels using supercritical carbon dioxide processing. The resulting aerogels had only the amine groups as initiators for the cyanoacrylate polymerizations, resulting in cyanoacrylate macromolecules that were higher in molecular weight than those observed with unmodified silica and that were covalently attached to the silica surface. Starting with aminated silica aerogels that were 0.075 g/cm(3) density, composite aerogels were made with densities up to 0.220 g/cm(3) and up to 31 times stronger (flexural strength) than the precursor aerogel and about 2.3 times stronger than an unmodified silica aerogel of the same density. PMID:20355935

  12. Degradation of biogenetic amines by gamma radiation process and identification by GC/MS

    International Nuclear Information System (INIS)

    Biogenic amines are low molecular weight organic bases with aliphatic (putrescine, cadaverine, spermine, spermidine), aromatic (tyramine, phenylethylamine) or heterocyclic (histamine, tryptamine) structures that can be found in several foods, in which they are mainly produced by microbial decarboxylation of amino acids. The reasons to control amines in food are their potential toxicity and their use like food quality markers. The consumption of food containing large amounts of biogenic amines can result in allergic reactions, characterized by difficulty in breathing, rash, vomiting, and hypertension. Biogenic amines are also known as possible precursors of carcinogens, such as N-nitrosamines. Traditionally, biogenic amine formation in food has been prevented, primarily by limiting microbial growth. However, control measures to reduce their levels once formed need to be also considered. The biogenic amines are frequently found in high concentrations and not reduced by high-temperature treatment, which makes difficult to use conventional methods of food preservation for this purpose. Food irradiation has been used in many countries for inhibition of sprouting, destruction of food borne insects, extension of shelf life or improvement of the technological of food. Irradiation is also known as a good method for inactivating pathogens and reducing microorganisms in food materials. Furthermore, besides the sanitary purpose, irradiation technology in new trials can be applied to induce radiolysis of toxic contaminants in food products reducing their content. This study has the objective to evaluate the effect of different gamma irradiation doses (1, 3 and 5kGy) in methanol solutions of three different biogenic amines: tryptamine, tyramine and b-phenylethylamine. The solutions were prepared using standard biogenic amines purchased from Sigma-Aldrich Brazil and methanol HPLC grade with a concentration of 100 μg/mL. They were irradiated in Centro Tecnologico do Exercito

  13. Degradation of biogenetic amines by gamma radiation process and identification by GC/MS

    Energy Technology Data Exchange (ETDEWEB)

    Cardozo, Monique; Souza, Stefania P. de; Lima, Keila dos S.C.; Lima, Antonio L. dos S., E-mail: santoslima@ime.eb.br [Departamento de Quimica - IME, Instituto Militar de Engenharia, RJ (Brazil)

    2011-07-01

    Biogenic amines are low molecular weight organic bases with aliphatic (putrescine, cadaverine, spermine, spermidine), aromatic (tyramine, phenylethylamine) or heterocyclic (histamine, tryptamine) structures that can be found in several foods, in which they are mainly produced by microbial decarboxylation of amino acids. The reasons to control amines in food are their potential toxicity and their use like food quality markers. The consumption of food containing large amounts of biogenic amines can result in allergic reactions, characterized by difficulty in breathing, rash, vomiting, and hypertension. Biogenic amines are also known as possible precursors of carcinogens, such as N-nitrosamines. Traditionally, biogenic amine formation in food has been prevented, primarily by limiting microbial growth. However, control measures to reduce their levels once formed need to be also considered. The biogenic amines are frequently found in high concentrations and not reduced by high-temperature treatment, which makes difficult to use conventional methods of food preservation for this purpose. Food irradiation has been used in many countries for inhibition of sprouting, destruction of food borne insects, extension of shelf life or improvement of the technological of food. Irradiation is also known as a good method for inactivating pathogens and reducing microorganisms in food materials. Furthermore, besides the sanitary purpose, irradiation technology in new trials can be applied to induce radiolysis of toxic contaminants in food products reducing their content. This study has the objective to evaluate the effect of different gamma irradiation doses (1, 3 and 5kGy) in methanol solutions of three different biogenic amines: tryptamine, tyramine and b-phenylethylamine. The solutions were prepared using standard biogenic amines purchased from Sigma-Aldrich Brazil and methanol HPLC grade with a concentration of 100 {mu}g/mL. They were irradiated in Centro Tecnologico do Exercito

  14. Bioactivation of Heterocyclic Aromatic Amines by UDP Glucuronosyltransferases.

    Science.gov (United States)

    Cai, Tingting; Yao, Lihua; Turesky, Robert J

    2016-05-16

    2-Amino-9H-pyrido[2,3-b]indole (AαC) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) are carcinogenic heterocyclic aromatic amines (HAA) that arise during the burning of tobacco and cooking of meats. UDP-glucuronosyltransferases (UGT) detoxicate many procarcinogens and their metabolites. The genotoxic N-hydroxylated metabolite of AαC, 2-hydroxyamino-9H-pyrido[2,3-b]indole (HONH-AαC), undergoes glucuronidation to form the isomeric glucuronide (Gluc) conjugates N(2)-(β-d-glucosidurony1)-2-hydroxyamino-9H-pyrido[2,3-b]indole (AαC-HON(2)-Gluc) and O-(β-d-glucosidurony1)-2-hydroxyamino-9H-pyrido[2,3-b]indole (AαC-HN(2)-O-Gluc). AαC-HON(2)-Gluc is a stable metabolite but AαC-HN(2)-O-Gluc is a biologically reactive intermediate, which covalently adducts to DNA at levels that are 20-fold higher than HONH-AαC. We measured the rates of formation of AαC-HON(2)-Gluc and AαC-HN(2)-O-Gluc in human organs: highest activity occurred with liver and kidney microsomes, and lesser activity was found with colon and rectum microsomes. AαC-HN(2)-O-Gluc formation was largely diminished in liver and kidney microsomes, by niflumic acid, a selective inhibitor UGT1A9. In contrast, AαC-HON(2)-Gluc formation was less affected and other UGT contribute to N(2)-glucuronidation of HONH-AαC. UGT were reported to catalyze the formation of isomeric Gluc conjugates at the N(2) and N3 atoms of 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine (HONH-PhIP), the genotoxic metabolite of PhIP. However, we found that the N3-Gluc of HONH-PhIP also covalently bound to DNA at higher levels than HONH-PhIP. The product ion spectra of this Gluc conjugate acquired by ion trap mass spectrometry revealed that the Gluc moiety was linked to the oxygen atom of HONH-PhIP and not the N3 imidazole atom of the oxime tautomer of HONH-PhIP as was originally proposed. UGT1A9, an abundant UGT isoform expressed in human liver and kidney, preferentially forms the O-linked Gluc conjugates of HONH

  15. SO2-Resistant Immobilized Amine Sorbents for CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Tumuluri, Uma [Univ. of Akron, OH (United States)

    2014-01-01

    The solid amine sorbent for CO2 capture process has advantages of simplicity and low operating cost compared to the MEA (monoethanolamine) process. Solid amine sorbents reported so far suffered from either low CO2 capture capacity or low stability in the flue gas environment. This project is aimed at developing a SO2-resistant solid amine sorbent for capturing CO2 from coal–fired power plants with SCR/FGD which emits SO2ranging from 15 to 30 ppm and NO ranging from 5 to 10 ppm. The amine sorbent we developed in a previous project degraded rapidly with 65% decrease in the initial capture capacity in presence of 1% SO2. This amine sorbent was further modified by coating with polyethyleneglycol (PEG) to increase the SO2-resistance. Polyethylene glycol (PEG) was found to decrease the SO2-amine interaction, resulting in the decrease in the maximum SO desorption temperature (Tmax ) of amine sorbent. The PEG-coated amine sorbent exhibited higher stability with only 40% decrease in the initial capture capacity compared to un-coated amine sorbents. The cost of the solid amine sorbent developed in this project is estimated to be less than $7.00/lb; the sorbent exhibited CO2 capture capacity more than 2.3 mmol/g. The results of this study provided the scientific basis for further development of SO2-resistant sorbents.

  16. Amine functionalized radiation-induced grafted water hyacinth fibers for Pb2+, Cu2+ and Cr3+ uptake

    International Nuclear Information System (INIS)

    An amine group containing fibrous adsorbent was prepared by reaction of grafted water hyacinth fibers with ethylenediamine. Glycidyl methacrylate (GMA) was grafted onto water hyacinth fibers using gamma radiation induced graft polymerization through simultaneous grafting technique and this was used as base material for producing the amine type adsorbents. The conversion of the epoxy group from GMA into amine group was investigated. The concentration of ethylenediamine solution that gave the highest amine functional group density was 50% by volume in 2-propanol. The amine functionalized water hyacinth fibers were characterized using Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscopy (ATR-FTIR), Thermogravimetric Analysis (TGA), and Energy Dispersive X-ray Spectroscopy (EDX). Information derived from these analyses confirms the successful conversion of the epoxy group. The amine-type adsorbent was evaluated for its uptake of Pb2+, Cu2+ and Cr3+ from aqueous solutions. The initial concentration of the metal ions and pH of the solutions were found to influence the amount of metal ions adsorbed by the amine-type adsorbent. The kinetics of adsorption was observed to follow Lagergren's first order equation. Results of ion sorption studies indicate that gamma radiation-induced grafting and subsequent chemical modification improved the ion sorption behaviour of water hyacinth fibers. - Highlights: • RIGP and amination imparted higher ion sorption capacity to water hyacinth fibers. • The epoxy group of grafted glycidyl methacrylate was reacted with ethylenediamine. • TGA, ATR-FTIR and EDX analysis confirmed successful amine functionalization. • The amine type fibrous adsorbent has higher affinity for Cu2+ and Pb2+ than Cr3+

  17. Anomalous length dependence of conductance of aromatic nanoribbons with amine anchoring groups

    KAUST Repository

    Bilić, Ante

    2012-09-06

    Two sets of aromatic nanoribbons, based around a common hexagonal scaffolding, with single and dual terminal amine groups have been considered as potential molecular wires in a junction formed by gold leads. Charge transport through the two-terminal device has been modeled using density functional theory (with and without self-interaction correction) and the nonequilibrium Green\\'s function method. The effects of wire length, multiple terminal contacts, and pathways across the junction have been investigated. For nanoribbons with the oligopyrene motif and conventional single amine terminal groups, an increase in the wire length causes an exponential drop in the conductance. In contrast, for the nanoribbons with the oligoperylene motif and dual amine anchoring groups the predicted conductance rises with the wire length over the whole range of investigated lengths. Only when the effects of self-interaction correction are taken into account, the conductance of the oligoperylene ribbons exhibits saturation for longer members of the series. The oligoperylene nanoribbons, with dual amine groups at both terminals, show the potential to fully harness the highly conjugated system of π molecular orbitals across the junction. © 2012 American Physical Society.

  18. Capture and separation of CO2 from flue gas by coupling free and immobilized amines

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel system has been proposed for the capture and separation of CO2 from flue gas. In this method, a resin isemployed to regenerate the amine capturing CO2 from flue gas atroom temperatures. The feasibility for the resin to regenerateamines such as MEA, MAE, TEA, and ammonia has been demonstrated. It was also discovered that the resin could be regenerated by hotwater.

  19. Synthesis of Novel 5-(-Substituted-Anilino)-8-Hydroxyquinolines via Hartwig-Buchwald Amination Reaction

    Indian Academy of Sciences (India)

    Walaa A E Omar; Osmo E O Hormi

    2015-11-01

    Three novel 5-(-substituted-anilino)-8-benzyloxyquinoline derivatives were efficiently synthesized via Hartwig–Buchwald amination reaction. The new 5-(-substituted-anilino)-8-benzyloxyquinolines were reduced for 1–3 h to give the corresponding 5-(-substituted-anilino)-8-hydroxyquinolines. Extending the reduction reaction time to 7 h afforded the corresponding 1,2,3,4-tetrahydro-8-hydroxyquinoline derivatives.

  20. A Colorimetric Sensor for Qualitative Discrimination and Quantitative Detection of Volatile Amines

    Directory of Open Access Journals (Sweden)

    Zhonglin Tang

    2010-06-01

    Full Text Available We have developed a novel colorimetric sensor based on a digital camera and white LED illumination. Colorimetric sensor arrays (CSAs were made from a set of six chemically responsive dyes impregnated on an inert substrate plate by solution casting. Six common amine aqueous solutions, including dimethylamine, triethylamine, diisopropyl-amine, aniline, cyclohexylamine, and pyridine vaporized at 25 °C and six health-related trimethylamine (TMA concentrations including 170 ppm, 51 ppm, 8 ppm, 2 ppm, 125 ppb and 50 ppb were analyzed by the sensor to test its ability for the qualitative discrimination and quantitative detection of volatile amines. We extracted the feature vectors of the CSA's response to the analytes from a fusional color space, which was obtained by conducting a joint search algorithm of sequential forward selection and sequential backward selection (SFS&SBS based on the linear discriminant criteria (LDC in a mixed color space composed of six common color spaces. The principle component analysis (PCA followed by the hierarchical cluser analysis (HCA were utilized to discriminate 12 analytes. Results showed that the colorimetric sensor grouped the six amine vapors and five TMA concentrations correctly, while TMA concentrations of 125 ppb and 50 ppb were indiscriminable from each other. The limitation of detection (LOD of the sensor for TMA was found to be lower than 50 ppb. The CSAs were reusable for TMA concentrations below 8 ppm.

  1. Resolving the stability and structure of strontium chloride amines from equilibrium pressures, XRD and DFT

    DEFF Research Database (Denmark)

    Lysgaard, Steen; Ammitzbøll, Andreas L.; Johnsen, Rune;

    2012-01-01

    Strontium chloride octamine, Sr(NH3)8Cl2, has been shown to be a highly efficient ammonia reservoir for selective catalytic reduction of NOx gases in vehicle exhaust and to hold great potential for indirect hydrogen storage. The possible applications of such metal amines depend explicitly on the ...

  2. Magnetic Silica Supported Copper: A Modular Approach to Aqueous Ullmann-type Amination of Aryl Halides

    Science.gov (United States)

    One-pot synthesis of magnetic silica supported copper catalyst has been described via in situ generated magnetic silica (Fe3O4@SiO2); the catalyst can be used for the efficacious amination of aryl halides in aqueous medium under microwave irradiation.

  3. Amine-modified ordered mesoporous silica: Effect of pore size on carbon dioxide capture

    Czech Academy of Sciences Publication Activity Database

    Zeleňák, V.; Badaničová, M.; Halamová, D.; Čejka, Jiří; Zukal, Arnošt; Murafa, Nataliya; Goerigk, G.

    2008-01-01

    Roč. 144, č. 2 (2008), s. 336-342. ISSN 1385-8947 R&D Projects: GA ČR GA203/08/0604 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z40320502 Keywords : mesoporous silica * hexagonal * amine * carbon dioxide Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.813, year: 2008

  4. Pyrylium Salts as Reactive Matrices for MALDI-MS Imaging of Biologically Active Primary Amines

    Science.gov (United States)

    Shariatgorji, Mohammadreza; Nilsson, Anna; Källback, Patrik; Karlsson, Oskar; Zhang, Xiaoqun; Svenningsson, Per; Andren, Per E.

    2015-06-01

    Many neuroactive substances, including endogenous biomolecules, environmental compounds, and pharmaceuticals possess primary amine functional groups. Among these are catecholamine neurotransmitters (e.g., dopamine), many substituted phenethylamines (e.g., amphetamine), as well as amino acids and neuropeptides. In most cases, mass spectrometric (ESI and MALDI) analyses of trace amounts of such compounds are challenging because of their poor ionization properties. We present a method for chemical derivatization of primary amines by reaction with pyrylium salts that facilitates their detection by MALDI-MS and enables the imaging of primary amines in brain tissue sections. A screen of pyrylium salts revealed that the 2,4-diphenyl-pyranylium ion efficiently derivatizes primary amines and can be used as a reactive MALDI-MS matrix that induces both derivatization and desorption. MALDI-MS imaging with such matrix was used to map the localization of dopamine and amphetamine in brain tissue sections and to quantitatively map the distribution of the neurotoxin β- N-methylamino-L-alanine.

  5. Factors Affecting Energy Barriers for Pyramidal Inversion in Amines and Phosphines: A Computational Chemistry Lab Exercise

    Science.gov (United States)

    Montgomery, Craig D.

    2013-01-01

    An undergraduate exercise in computational chemistry that investigates the energy barrier for pyramidal inversion of amines and phosphines is presented. Semiempirical calculations (PM3) of the ground-state and transition-state energies for NR[superscript 1]R[superscript 2]R[superscript 3] and PR[superscript 1]R[superscript 2]R[superscript 3] allow…

  6. Rodent repellent studies. IV. Preparation and properties of trinitrobenzene-aryl amine complexes

    Science.gov (United States)

    DeWitt, J.B.; Bellack, E.; Welch, J.F.

    1953-01-01

    Data are presented on methods of preparation, chemical arid physical characteristics, toxicity, and repellency to rodents of complexes of symmetrical trinitrohenzene with various aromatic amines: When applied in suitable carriers or incorporated in plastic .films, members of this series ofmaterials were shown to offer significant increases in time required by wild rodents to damage common packaging materials.

  7. Solid-phase oligosaccharide synthesis with tris(alkoxy)benzyl amine (BAL) safety-catch anchoring

    DEFF Research Database (Denmark)

    Tolborg, Jakob Fjord; Jensen, Knud Jørgen

    2000-01-01

    A tris(alkoxy)benzylamine (BAL) handle strategy was developed for safety-catch anchoring of D-glucosamine derivatives in solid-phase synthesis of oligosaccharides; the linkage between the BAL handle and the amine proved stable to conc. TFA and Lewis acids, but after N-acylation the amide could be...

  8. Amide and amine nucleophiles in polar radical crossover cycloadditions: synthesis of γ-lactams and pyrrolidines.

    Science.gov (United States)

    Gesmundo, Nathan J; Grandjean, Jean-Marc M; Nicewicz, David A

    2015-03-01

    In this work we present a direct catalytic synthesis of γ-lactams and pyrrolidines from alkenes and activated unsaturated amides or protected unsaturated amines, respectively. Using a mesityl acridinium single electron photooxidant and a thiophenol cocatalyst under irradiation, we are able to directly forge these important classes of heterocycles with complete regiocontrol. PMID:25695366

  9. UNIQUAC interaction parameters for alkane/amine systems determined by Molecular Mechanics

    DEFF Research Database (Denmark)

    Jonsdottir, Svava Osk; Klein, R. A.; Rasmussen, Kjeld

    UNIQUAC interaction parameters have been successfully determined for three alkane/primary amine systems using a Molecular Mechanics method called the Consistent Force Field. Interaction parameters for alkane/alkane and alkane/ketone systems had been determined previously using this method and in...

  10. Interface effects on tunneling magnetoresistance in organic spintronics with flexible amine-Au links.

    Science.gov (United States)

    Gorjizadeh, Narjes; Quek, Su Ying

    2013-10-18

    Organic spintronics is a promising emerging field, but the sign of the tunneling magnetoresistance (TMR) is highly sensitive to interface effects, a crucial hindrance to applications. A key breakthrough in molecular electronics was the discovery of amine-Au link groups that give a reproducible conductance. Using first-principles calculations, we predict that amine-Au links give improved reproducibility in organic spintronics junctions with Au-covered Fe leads. The Au layers allow only states with sp character to tunnel into the molecule, and the flexibility of amine-Au links results in a narrow range of TMR for a fixed number of Au layers. Even as the Au thickness changes, the TMR remains positive as long as the number of Au layers is the same on both sides of the junction. Since the number of Au layers on Fe surfaces or Fe nanoparticles can now be experimentally controlled, amine-Au links provide a route towards robust TMR in organic spintronics. PMID:24060599

  11. Gas Permeability and Selectivity of Synthesized Diethanol Amine-Polysulfone/Polyvinylacetate Blend Membranes

    Directory of Open Access Journals (Sweden)

    Asim Mushtaq

    2014-08-01

    Full Text Available The control of anthropogenic carbon dioxide release is one of the most challenging environmental problem faced by developing countries, as the interfering of atmospheric carbon dioxide level and climate revolutionize. An rising technology is the membrane gas separation, which is more dense, energy efficient and possibly more economical than past technologies, such as solvent absorption. Amine has a greater efficiency for removal of carbon dioxide. The blending technique not only provides improved chemical and thermal stability but is also efficient enough to improve the perm-selective properties with economical viability. In this study, research will be carried out to study the gas permeability behavior of glassy Polysulfone and Polyvinyl acetate rubbery polymeric blend membranes with diethanol amine. Polymeric amine blend membranes with different blending ratios were prepared in dimethyl acetamide solvent, flat sheet membrane were developed with enhance properties. We were studied PSU/PVAc blend with DEA amine using a gas permeability application for CO2 and CH4 at different feed pressures.

  12. Guidance document on fat reduction factor, functional barrier concept, phthalates and primary aromatic amines

    DEFF Research Database (Denmark)

    Hoekstra, Eddo J.; Petersen, Jens Højslev; Bustos, Juana

    functional barrier, and the restrictions for certain phthalates and primary aromatic amines. The Regulation applies from 1 May 2011. The network of the European Union Reference Laboratory and the National Reference Laboratories for food contact materials created a Task Force in order to give guidance on...

  13. N-[1-(2,5-Dimethyl-3-thienylethylidene]-1,3-benzothiazol-2-amine

    Directory of Open Access Journals (Sweden)

    Abdullah Mohamed Asiri

    2010-03-01

    Full Text Available The title compound, N-[1-(2,5-dimethyl-3-thienylethylidene]-1,3-benzothiazol-2-amine has been synthesized by condensation of 2-aminobenzothiazole and 3-acetyl-2,5-dimethylthiophene in ethanol. The structure of this new compound was confirmed by elemental analysis, IR, 1H-NMR, 13C-NMR and EI-MS spectral analysis.

  14. Aggressiveness and brain amines in pigs fed the ß-adrenoreceptor agonist Ractopamine

    Science.gov (United States)

    The objectives of this study were to evaluate the effects of the widely used feed additive Ractopamine (RAC), gender and social rank on aggressiveness and concentrations of brain amines in finishing pigs. Thirty-two barrows and 32 gilts (4 pigs/pen/gender) were fed either control or RAC (5 mg/kg/2 w...

  15. Amino olefin nickel(I) and nickel(0) complexes as dehydrogenation catalysts for amine boranes

    NARCIS (Netherlands)

    M. Vogt; B. de Bruin; H. Berke; M. Trincado; H. Grützmacher

    2011-01-01

    A rare paramagnetic organometallic nickel(I) olefin complex can be isolated using the ligand bis(5H-dibenzo[a,d]cyclohepten-5-yl)amine. This complex and related nickel(0) hydride complexes show very high catalytic activity in the dehydrogenation of dimethylamino borane with release of one equivalent

  16. Vinyl ester resin and process for curing same with ionizing radiation in the presence of amines

    International Nuclear Information System (INIS)

    The addition of about 1.5 to 5 weight percent of certain amines to a thermosettable mixture of a nonvolatile vinyl monomer and a polymerizable vinyl ester resin reduces the dosage level of ionizing radiation required to cure the mixture

  17. Copper and amine free Sonogashira cross-coupling reaction catalyzed by efficient diphosphane-palladium catalyst

    Institute of Scientific and Technical Information of China (English)

    Ting He; Lei Lei Wu; Xing Li Fu; Hai Yan Fu; Hua Chen; Rui Xiang Li

    2011-01-01

    The commercially available diphosphane ligand MeO-BIPHEP was first investigated in the palladium-catalyzed Sonogashira reaction in the absence of copper and amine. The coupling of various aryl bromides and aryl chlorides with phenylacetylene gave moderate to excellent yields.

  18. 40 CFR 721.10143 - Amines, bis (C11-14-branched and linear alkyl).

    Science.gov (United States)

    2010-07-01

    ... linear alkyl). 721.10143 Section 721.10143 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10143 Amines, bis (C11-14-branched and linear alkyl). (a) Chemical..., bis (C11-14-branched and linear alkyl) (PMN P-06-733; CAS No. 900169-60-0) is subject to...

  19. Impact of environmental exposures on the mutagenicity/carcinogenicity of heterocyclic amines

    International Nuclear Information System (INIS)

    Carcinogenic heterocyclic amines are produced from overcooked foods and are highly mutagenic in most short-term test systems. One of the most abundant of these amines, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), induces breast, colon and prostate tumors in rats. Human dietary epidemiology studies suggest a strong correlation between either meat consumption or well-done muscle meat consumption and cancers of the colon, breast, stomach, lung and esophagus. For over 20 years our laboratory has helped define the human exposure to these dietary carcinogens. In this report we describe how various environmental exposures may modulate the risk from exposure to heterocyclic amines, especially PhIP. To assess the impact of foods on PhIP metabolism in humans, we developed an LC/MS/MS method to analyze the four major PhIP urinary metabolites following the consumption of a single portion of grilled chicken. Adding broccoli to the volunteers' diet altered the kinetics of PhIP metabolism. At the cellular level we have found that PhIP itself stimulates a significant estrogenic response in MCF-7 cells, but even more interestingly, co-incubation of the cells with herbal teas appear to enhance the response. Numerous environmental chemicals found in food or the atmosphere can impact the exposure, metabolism, and cell proliferation response of heterocyclic amines

  20. An amine-derivatized, DOTA-loaded polymeric support for Fmoc Solid Phase Peptide Synthesis

    OpenAIRE

    Yoo, Byunghee; Sheth, Vipul R.; Pagel, Mark D.

    2009-01-01

    An amine-derivatized DOTA has been used to modify the surface of a polymeric support for conventional Solid Phase Peptide Synthesis (SPPS) following standard Fmoc chemistry methods. This methodology was used to synthesize a peptide-DOTA conjugate that was demonstrated to be a PARACEST MRI contrast agent. Therefore, this synthesis methodology can facilitate Fmoc SPPS of molecular imaging contrast agents.

  1. Introduction of various amine groups onto polyethylene bead prepared by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Complete text of publication follows. Radiation-induced graft polymerization is a good method for modification of chemical and physical properties of polymeric materials because it can endow properties such as membrane quality, ion exchange, blood compatibility, dyeability, protein adsorption, and immobilization of bioactive materials. Polyethylene microbead is very useful material due to the following advantages; low price, simple purchase, high sensitivity, and simple analysis. On the other hand, the epoxy group of the glycidyl methacrylate (GMA) can easily be converted to the various functional groups such as amines, alcohols, phosphoric acid, sulfonic acid, and amino acid, etc. Cyclodextrin have been applied universally in various industries such as foods, cosmetics, pharmaceutical industry, analytical chemistry, and chemical industry. In order to obtain cyclodextrins, polyethylene microbead with the epoxy group were prepared by radiation-induced graft polymerization of GMA onto polyethylene microbead. The physical and chemical properties of the GMA-induced polyethylene microbeads were investigated by IR, thermal analysis (TGA/DSC), and SEM, respectively. Subsequently, the various amine groups such as diethylamine. diethylenetriamine, triethylamine, triethylenetetramine, and 1,6-hexanediamine were induced onto the epoxy group in polyethylene microbead. Finally, cyclodextrin glucanotransferase were immobilized onto polyethylene microbead with various amines under the various experimental conditions, such as pH, amin content, immobilization time, and etc. The activity of CGTase-immobilized polyethylene microbead was determined by Phenolphthein method. The production of the cyclodextrins from starch is in progress

  2. Amine donor and acceptor influence on the thermodynamics of ω-transaminase reactions

    DEFF Research Database (Denmark)

    Gundersen, Maria T.; Abu, Rohana; Schürmann, Martin; Woodley, John

    2015-01-01

    In recent years biocatalytic transamination using ω-transaminase has become established as one of the most interesting routes to synthesize chiral amines with a high enantiomeric purity, especially in the pharmaceutical sector where the demand for such compounds is high. Nevertheless, one limitat...

  3. Two food-borne heterocyclic amines: Metabolism and DNA adduct formation of amino-alpha-carbolines

    DEFF Research Database (Denmark)

    Frederiksen, Hanne

    2005-01-01

    -adducts have also been studied. Characteristic for the amino-a-carbolines are that relatively large amounts of these compounds in rat and human hepatic microsomes are activated to potent carcinogenic compounds compared with other heterocyclic amines, but further in vivo studies of the amino-a-carbolines are...

  4. Identification of primary amines in Titan tholins using microchip nonaqueous capillary electrophoresis

    Science.gov (United States)

    Cable, M. L.; Hörst, S. M.; He, C.; Stockton, A. M.; Mora, M. F.; Tolbert, M. A.; Smith, M. A.; Willis, P. A.

    2014-10-01

    Titan, the moon of Saturn with a thick atmosphere and an active hydrocarbon-based weather cycle, is considered the best target in the solar system for the study of organic chemistry on a planetary scale. Microfluidic devices that employ liquid phase techniques such as capillary electrophoresis with ultrasensitive laser-induced fluorescence detection offer a unique solution for in situ analysis of complex organics on Titan. We previously reported a protocol for nonaqueous microfluidic analysis of primary aliphatic amines in ethanol, and demonstrated separations of short- and long-chain amines down to -20 °C. We have optimized this protocol further, and used it to analyze Titan aerosol analogues (tholins) generated in two separate laboratories under a variety of different conditions. Ethylamine was a major product in all samples, though significant differences in amine content were observed, in particular for long-chain amines (C12-C27). This work validates microfluidic chemical analysis of complex organics with relevance to Titan, and represents a significant first step in understanding tholin composition via targeted functional group analysis.

  5. Impact of Environmental Exposures on the Mutagenicity/Carcinogenicity of Heterocyclic Amines

    Energy Technology Data Exchange (ETDEWEB)

    Felton, J S; Knize, M G; Bennett, L M; Malfatti, M A; Colvin, M E; Kulp, K S

    2003-12-19

    Carcinogenic heterocyclic amines are produced from overcooked foods and are highly mutagenic in most short-term test systems. One of the most abundant of these amines, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), induces breast, colon and prostate tumors in rats. Human dietary epidemiology studies suggest a strong correlation between either meat consumption or well-done muscle meat consumption and cancers of the colon, breast, stomach, lung and esophagus. For over 20 years our laboratory has helped define the human exposure to these dietary carcinogens. In this report we describe how various environmental exposures may modulate the risk from exposure to heterocyclic amines, especially PhIP. To assess the impact of foods on PhIP metabolism in humans, we developed an LC/MS/MS method to analyze the four major PhIP urinary metabolites following the consumption of a single portion of grilled chicken. Adding broccoli to the volunteers' diet altered the kinetics of PhIP metabolism. At the cellular level we have found that PhIP itself stimulates a significant estrogenic response in MCF-7 cells, but even more interestingly, co-incubation of the cells with herbal teas appear to enhance the response. Numerous environmental chemicals found in food or the atmosphere can impact the exposure, metabolism, and cell proliferation response of heterocyclic amines.

  6. The Reactions of 3,7—Dinitrodibenzobromolium Salt with Some Amines

    Institute of Scientific and Technical Information of China (English)

    ZiJieHOU; XianHuaPAN; 等

    2002-01-01

    The reactions of 3,7-dinitrodibenzobromolium salt with some amines were studied. A reaction mechanism based on the structure of the major product 6 and the minor product 7 was proposed. The reaction was considered to proceed via a substituted benzyene intermediate.

  7. Ionic networks derived from the protonation of dendritic amines with carboxylic acid end‐functionalized PEGs

    DEFF Research Database (Denmark)

    Gonzalez, Lidia; Skov, Anne Ladegaard; Hvilsted, Søren

    2013-01-01

    weights (Mn ∼ 250 and Mn ∼ 600) are reported. Likewise, an ionic network based on PPI G1 and a long αω‐dicarboxylic acid functionalized PEG (Mn ∼ 4800) were evaluated. Simpler ionic structures based on tris(2‐aminoethyl)amine or hexamethylene diamine and the short DiCOOH‐PEGs are also investigated. The...

  8. A new efficient synthesis of isothiocyanates from amines using di-tert-butyl dicarbonate

    DEFF Research Database (Denmark)

    Munch, Henrik; Hansen, Jon S.; Pittelkow, Michael;

    2008-01-01

    Alkyl and aryl amines are converted smoothly to the corresponding isothiocyanates via the dithiocarbamates in good to excellent yields using di-tert-butyl dicarbonate (Boc(2)O) and 1-3 mol% of DMAP or DABCO as catalyst. As most of the byproducts are volatile, the work-up involves simple evaporation...

  9. Direct Amination of Nitro(pentafluorosulfanyl)benzenes through Vicarious Nucleophilic Substitution of Hydrogen

    Czech Academy of Sciences Publication Activity Database

    Pastýříková, Tereza; Iakobson, George; Vida, Norbert; Pohl, Radek; Beier, Petr

    -, č. 11 (2012), s. 2123-2126. ISSN 1434-193X R&D Projects: GA ČR GAP207/12/0072 Institutional research plan: CEZ:AV0Z40550506 Keywords : sulfur * amination * nucleophilic substitution * nitrogen heterocycles Subject RIV: CC - Organic Chemistry Impact factor: 3.344, year: 2012

  10. Polyvinyl alcohol electrospun nanofibers containing Ag nanoparticles used as sensors for the detection of biogenic amines

    Science.gov (United States)

    Marega, Carla; Maculan, Jenny; Rizzi, Gian Andrea; Saini, Roberta; Cavaliere, Emanuele; Gavioli, Luca; Cattelan, Mattia; Giallongo, Giuseppe; Marigo, Antonio; Granozzi, Gaetano

    2015-02-01

    Polyvinyl alcohol (PVA) electrospun nanofibers containing Ag nanoparticles (NPs) have been deposited on glass substrates. The aim of the work was to test the feasibility of this approach for the detection of biogenic amines by using either the Ag localized surface plasmon resonance quenching caused by the adsorption of amines on Ag NPs or by detecting the amines by surface enhanced Raman spectroscopy (SERS) after adsorption, from the gas phase, on the metal NPs. Two different approaches have been adopted. In the first one an ethanol/water solution containing AgNO3 was used directly in the electrospinning apparatus. In this way, a simple heat treatment of the nanofibers mat was sufficient to obtain the formation of Ag NPs inside the nanofibers and a partial cross-link of PVA. In the second procedure, the Ag NPs were deposited on PVA nanofibers by using the supersonic cluster beam deposition method, so that a beam of pure Ag NPs of controlled size was obtained. Exposure of the PVA mat to the beam produced a uniform distribution of the NPs on the nanofibers surface. Ethylendiamine vapors and volatile amines released from fresh shrimp meat were chemisorbed on the nanofibers mats. A SERS spectrum characterized by a diagnostic Ag-N stretching vibration at 230 cm-1 was obtained. The results allow to compare the two different approaches in the detection of ammines.

  11. Polyvinyl alcohol electrospun nanofibers containing Ag nanoparticles used as sensors for the detection of biogenic amines

    International Nuclear Information System (INIS)

    Polyvinyl alcohol (PVA) electrospun nanofibers containing Ag nanoparticles (NPs) have been deposited on glass substrates. The aim of the work was to test the feasibility of this approach for the detection of biogenic amines by using either the Ag localized surface plasmon resonance quenching caused by the adsorption of amines on Ag NPs or by detecting the amines by surface enhanced Raman spectroscopy (SERS) after adsorption, from the gas phase, on the metal NPs. Two different approaches have been adopted. In the first one an ethanol/water solution containing AgNO3 was used directly in the electrospinning apparatus. In this way, a simple heat treatment of the nanofibers mat was sufficient to obtain the formation of Ag NPs inside the nanofibers and a partial cross-link of PVA. In the second procedure, the Ag NPs were deposited on PVA nanofibers by using the supersonic cluster beam deposition method, so that a beam of pure Ag NPs of controlled size was obtained. Exposure of the PVA mat to the beam produced a uniform distribution of the NPs on the nanofibers surface. Ethylendiamine vapors and volatile amines released from fresh shrimp meat were chemisorbed on the nanofibers mats. A SERS spectrum characterized by a diagnostic Ag–N stretching vibration at 230 cm−1 was obtained. The results allow to compare the two different approaches in the detection of ammines. (paper)

  12. Synthesis of Derivatives of Biogenic Amines Labelled with Radioactive Tracers for Brain Imaging

    Directory of Open Access Journals (Sweden)

    Arturo A. Vitale

    2000-03-01

    Full Text Available Endogenous derivatives of biogenic amines, such as phenethylamines, indolalkylamines and harmines, have been extensively studied as usual constituents of body fluids. Methylated derivatives of indolalkylamines have been also related to mental disorders, e.g. schizophrenia and hallucination.

  13. Effect of biogenic amines on the mating and egg-laying behaviors in the stable fly

    Science.gov (United States)

    The stable fly Stomoxys calcitrans (L.) (Diptera: Muscidae), is one of the most significant biting fly pests affecting livestock.The annual economic damage to the U.S. cattle industry is estimated at over one billion US dollars. Biogenic amines are known to play critical roles in feeding and reprodu...

  14. Alkylamino derivatives of 4-aminomethylpyridine as inhibitors of copper-containing amine oxidases.

    Science.gov (United States)

    Bertini, Vincenzo; Buffoni, Franca; Ignesti, Giovanni; Picci, Nevio; Trombino, Sonia; Iemma, Francesca; Alfei, Silvana; Pocci, Marco; Lucchesini, Francesco; De Munno, Angela

    2005-02-10

    The first substratelike, reversible inhibitors of different copper amine oxidases (CAOs) with IC50 (M) as low as 2.0 x 10(-8) corresponding to derivatives of 4-aminomethylpyridine with alkoxy (1a-d), alkylthio (2a,b), and alkylamino (3a-e, 4a-j) groups in the positions 3 and 5 have been prepared and studied. The inhibitors 1a-d are active on benzylamine oxidase and semicarbazide-sensitive amine oxidase and are very selective with respect to diamine oxidase, lysyl oxidase, and monoamine oxidases. The inhibitors 2a,b are selective for benzylamine oxidase whereas 2a is also a new type of good substrate of diamine oxidase. The inhibitors 3a-e and 4a-j are substratelike, reversible, nonselective inhibitors of various CAOs including pea seedling amine oxidase and Hansenula polymorpha amine oxidase, whose enzymatic sites are known from X-ray structure determinations. The inhibitors 3b,c and 4b,c are excellent substratelike tools for studies correlating CAOs that afford crystals suitable for X-ray structure determinations with CAOs from mammals. PMID:15689151

  15. Density Functional Investigation of Graphene Doped with Amine-Based Organic Molecules

    Directory of Open Access Journals (Sweden)

    Yeun Hee Hwang

    2015-01-01

    Full Text Available To improve the electronic properties of graphene, many doping techniques have been studied. Herein, we investigate the electronic and molecular structure of doped graphene using density functional theory, and we report the effects of amine-based benzene dopants adsorbed on graphene. Density functional theory (DFT calculations were performed to determine the role of amine-based aromatic compounds in graphene doping. These organic molecules bind to graphene through long-range interactions such as π-π interactions and C-H⋯π hydrogen bonding. We compared the electronic structures of pristine graphene and doped graphene to understand the electronic structure of doped graphene at the molecular level. Also, work functions of doped graphene were obtained from electrostatic potential calculations. A decrease in the work function was observed when the amine-based organic compounds were adsorbed onto graphene. Because these systems are based on physisorption, there was no obvious band structure change at point K at the Fermi level after doping. However, the amine-based organic dopants did change the absolute Fermi energy levels. In this study, we showed that the Fermi levels of the doped graphene were affected by the HOMO energy level of the dopants and by the intermolecular charge transfer between the adsorbed molecules and graphene.

  16. Palladium-catalysed transannular C-H functionalization of alicyclic amines

    Science.gov (United States)

    Topczewski, Joseph J.; Cabrera, Pablo J.; Saper, Noam I.; Sanford, Melanie S.

    2016-03-01

    Discovering pharmaceutical candidates is a resource-intensive enterprise that frequently requires the parallel synthesis of hundreds or even thousands of molecules. C-H bonds are present in almost all pharmaceutical agents. Consequently, the development of selective, rapid and efficient methods for converting these bonds into new chemical entities has the potential to streamline pharmaceutical development. Saturated nitrogen-containing heterocycles (alicyclic amines) feature prominently in pharmaceuticals, such as treatments for depression (paroxetine, amitifadine), diabetes (gliclazide), leukaemia (alvocidib), schizophrenia (risperidone, belaperidone), malaria (mefloquine) and nicotine addiction (cytisine, varenicline). However, existing methods for the C-H functionalization of saturated nitrogen heterocycles, particularly at sites remote to nitrogen, remain extremely limited. Here we report a transannular approach to selectively manipulate the C-H bonds of alicyclic amines at sites remote to nitrogen. Our reaction uses the boat conformation of the substrates to achieve palladium-catalysed amine-directed conversion of C-H bonds to C-C bonds on various alicyclic amine scaffolds. We demonstrate this approach by synthesizing new derivatives of several bioactive molecules, including varenicline.

  17. Direct asymmetric dearomatization of 2-naphthols by scandium-catalyzed electrophilic amination.

    Science.gov (United States)

    Nan, Jiang; Liu, Jingjing; Zheng, Huayu; Zuo, Zhijun; Hou, Lei; Hu, Huaiming; Wang, Yaoyu; Luan, Xinjun

    2015-02-16

    Catalytic asymmetric aminative dearomatization of 1-substituted 2-naphthols was successfully implemented with electrophilic azodicarboxylates under the catalysis of chiral Sc(III)/pybox complexes. This intermolecular reaction represents a hitherto unknown enantioselective C-N bond-forming process through direct dearomatization of phenolic compounds to generate chiral nitrogen-containing quaternary carbon stereocenters. PMID:25564754

  18. DFT Rationalization of the Diverse Outcomes of the Iodine(III)-Mediated Oxidative Amination of Alkenes.

    Science.gov (United States)

    Funes-Ardoiz, Ignacio; Sameera, W M C; Romero, R Martín; Martínez, Claudio; Souto, José A; Sampedro, Diego; Muñiz, Kilian; Maseras, Feliu

    2016-05-23

    A computational study of the mechanism for the iodine(III)-mediated oxidative amination of alkenes explains the experimentally observed substrate dependence on product distribution. Calculations with the M06 functional have been carried out on the reaction between PhI(N(SO2 Me)2 )2 and three different representative substrates: styrene, α-methylstyrene, and (E)-methylstilbene. All reactions start with electrophilic attack by a cationic PhI(N(SO2 Me)2 )(+) unit on the double bond, and formation of an intermediate with a single C-I bond and a planar sp(2) carbocationic center. The major path, leading to 1,2-diamination, proceeds through a mechanism in which the bissulfonimide initially adds to the alkene through an oxygen atom of one sulfonyl group. This behavior is now corroborated by experimental evidence. An alternative path, leading to an allylic amination product, takes place through deprotonation at an allylic C-H position in the common intermediate. The regioselectivity of this amination depends on the availability of the resonant structures of an alternate carbocationic intermediate. Only in cases where a high electronic delocalization is possible, as in (E)-methylstilbene, does the allylic amination occur without migration of the double bond. PMID:27106535

  19. Organocatalytic asymmetric allylic amination of Morita–Baylis–Hillman carbonates of isatins

    Directory of Open Access Journals (Sweden)

    Hang Zhang

    2012-08-01

    Full Text Available The investigation of a Lewis base catalyzed asymmetric allylic amination of Morita–Baylis–Hillman carbonates derived from isatins afforded an electrophilic pathway to access multifunctional oxindoles bearing a C3-quaternary stereocenter, provided with good to excellent enantioselectivity (up to 94% ee and in high yields (up to 97%.

  20. Method of preparing water purification membranes. [polymerization of allyl amine as thin films in plasma discharge

    Science.gov (United States)

    Hollahan, J. R.; Wydeven, T. J., Jr. (Inventor)

    1974-01-01

    Allyl amine and chemically related compounds are polymerized as thin films in the presence of a plasma discharge. The monomer compound can be polymerized by itself or in the presence of an additive gas to promote polymerization and act as a carrier. The polymerized films thus produced show outstanding advantages when used as reverse osmosis membranes.

  1. Synthesis and fungicidal activity of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines

    Institute of Scientific and Technical Information of China (English)

    Hui Chao Li; Bao Shan Chai; Zhi Nian Li; Ji Chun Yang; Chang Ling Liu

    2009-01-01

    A number of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines were synthesized. The structures of these new compounds were confirmed by ~1H NMR, IR and elemental analysis. Biological evaluation in the greenhouse showed several compounds have good fungicidal activities at 25 mg/L.

  2. Synthesis of novel aminated cellulose microsphere adsorbent for efficient Cr(VI) removal

    Science.gov (United States)

    Yu, Tianlin; Liu, Siqi; Xu, Min; Peng, Jing; Li, Jiuqiang; Zhai, Maolin

    2016-08-01

    A novel aminated cellulose microsphere adsorbent (CVN) was successfully prepared by radiation-induced graft polymerization of vinylbenzyl chloride (VBC) onto cellulose microsphere (CMS), followed by amination. Micro-FTIR, XPS and SEM confirmed the structure of CVN. The adsorption behavior of Cr(VI) onto CVN from solution was well fitted by the pseudo-second order kinetic model. The isothermal adsorption of Cr(VI) was observed at pH 4.68 with adsorption capacity of 129 mg/g in accordance with Langmuir thermal model, and the removal of Cr(VI) from solution could be 91% at a low amount (20 mg) of adsorbent. The best pH for adsorption of Cr(VI) was nearly 3.08, and with the increasing of temperature, the adsorption capacity of Cr(VI) increased. XPS analysis confirmed the adsorption mechanism of Cr(VI) was ion-exchange mechanism, while common co-ions such as Na+, Mg2+, Cu2+, Ca2+, Zn2+, Ni2+, Cl-, NO3- has no significant effect on the adsorption capacity of Cr(VI), and the Cr(VI) removal of 80% still could be obtained compared with that of fresh CVN adsorbent. Finally, spent CVN could be regenerated under 2 mol/L NaCl. The work indicated that aminated cellulose adsorbent could be prepared successfully by radiation-induced grafting and amination and CVN is a promising bio-adsorbent in the removing Cr(VI) from waste water.

  3. Ozone stress modulates amine oxidase and lipoxygenase expression in lentil (Lens culinaris) seedlings

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Maccarrone, M.; Veldink, G.A.; Finazzi Agrò, A.

    1997-01-01

    The effect of ozone stress on polyamine metabolism and membrane lipid peroxidation in lentil seedlings through the amine oxidase and lipoxygenase activity and expression has been investigated. Ozone is shown to control the expression of these enzymes at the transcriptional level, down-regulating the

  4. NaBH4/C: A Convenient System for Reductive Amination of Aldehydes

    Directory of Open Access Journals (Sweden)

    Sajjad Taie Hasanloie

    2014-03-01

    Full Text Available In this context, NaBH4 in the presence of activated charcoal has been used for thereductive aminationofa varietyof aldehydes withanilines. The reductive amination reactions have been performed within 60-100 min in THFunder reflux conditionsin high to excellent yields of products (85-90%.

  5. A wet electrostatic precipitator (WESP) as countermeasure to mist formation in amine based carbon capture

    NARCIS (Netherlands)

    Mertens, J.; Anderlohr, C.; Rogiers, P.; Brachert, L.; Khakharia, P.M.; Goetheer, E.L.V.; Schaber, K.

    2014-01-01

    This study is to our knowledge the first to evaluate the potential of a wet electrostatic precipitator (WESP) to prevent aerosol formation issues inside amine based carbon capture installations. A WESP is a suitable option since this study proves that it is very efficient for the removal of the mist

  6. The Use of Amine Reclaimer Wastes as a NOx Reduction Agent

    DEFF Research Database (Denmark)

    Botheju, Deshai; Glarborg, Peter; Tokheim, Lars-Andre

    2013-01-01

    Amine reclaimer wastes (ARW) generated in carbon capture and sequestration (CCS) is categorized as a hazardous waste which needs proper disposal. The proposal described in this paper can bring about a multi-effective solution to the problem of CCS waste handling. Both the pilot scale and the full...

  7. Focal Adhesion of Osteoblastic Cells on Titanium Surface with Amine Functionalities Formed by Plasma Polymerization

    Science.gov (United States)

    Song, Heesang; Jung, Sang Chul; Kim, Byung Hoon

    2012-08-01

    To enhance the focal adhesion of osteoblastic cells on a titanium surface, plasma polymerized allyl amine (AAm) thin films were deposited by plasma polymerization. This plasma polymer functionalization of titanium is advantageous for osteoblastic focal adhesion formation. Such Ti surfaces are useful for the fabrication of titanium-based dental implants for enhancement of osseointegration.

  8. New amidines from intramolecular cyclization in triflic acid of nitroketene aminals with a tethered phenyl ring

    Indian Academy of Sciences (India)

    Soro Yaya; Bamba Fanté; Siaka Sorho; Coustard Jean-Marie; Adima A Augustin

    2007-05-01

    Nitroketene aminals with a tethered phenyl group underwent an intramolecular cyclization in trifluoromethanesulfonic acid to afford the corresponding N-(3-ethyl-hydrohydroxyiminobenzocycloalkenylidene) methylamine trifluoromethanesulfonate. The yields were fair to good excepted for the starting compound 1-[N-ethyl-N-(2-phenylethyl)amino]-1-methylamino-2-nitroethene.

  9. Palladium-Catalyzed Carbonylation of Primary Amines in Supercritical Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    李金恒; 江焕峰; 陈鸣才

    2001-01-01

    The chemoselectity of the palladimm-catalyzed carbonylation of amines was affected by the addition of MeOH in supercritical carbon dioxide. The results show different selectivity in supercritical carbon dioxide CO2(sc) from that in alcohol.Methyl carbamate and its derivatives were obtained in high yields in CO2(sc).

  10. Cancer risk assessment of azo dyes and aromatic amines from garment and footwear

    NARCIS (Netherlands)

    Zeilmaker MJ; Kroese ED; Haperen P van; Veen MP van; Bremmer HJ; Kranen HJ van; Wouters MFA; Janus J; LBM

    1999-01-01

    A quantitative assessment was performed to estimate the cancer risk to individuals wearing garment and footwear coloured with azo dyes. Basically, the risk assessment consists of both a comparison of the (estimated) level of aromatic amines which, during the wearing of garment and footwear, enters

  11. Polyvinylchloride/clay nanocomposites based on the alkyl-amine intercalates with different length of chain

    Czech Academy of Sciences Publication Activity Database

    Kalendová, A.; Pospíšil, M.; Kovářová, L.; Měřínská, D.; Šimoník, J.; Čapková, P.; Valášková, M.; Vlková, Helena

    Akron : Polymer Processing Society , 2004. s. 248. [Polymer Processing Society Annual Meeting. 20.06.2004-24.06.2004, Akron] R&D Projects: GA AV ČR KSK4050111 Keywords : polyvinylchloride/clay * alkyl-amine intercalates * polymer nanotechnology Subject RIV: CD - Macromolecular Chemistry

  12. Characterization of route specific impurities found in methamphetamine synthesized by the Leuckart and reductive amination methods.

    Science.gov (United States)

    Kunalan, Vanitha; Nic Daéid, Niamh; Kerr, William J; Buchanan, Hilary A S; McPherson, Allan R

    2009-09-01

    Impurity profiling of seized methamphetamine can provide very useful information in criminal investigations and, specifically, on drug trafficking routes, sources of supply, and relationships between seizures. Particularly important is the identification of "route specific" impurities or those which indicate the synthetic method used for manufacture in illicit laboratories. Previous researchers have suggested impurities which are characteristic of the Leuckart and reductive amination (Al/Hg) methods of preparation. However, to date and importantly, these two synthetic methods have not been compared in a single study utilizing methamphetamine hydrochloride synthesized in-house and, therefore, of known synthetic origin. Using the same starting material, 1-phenyl-2-propanone (P2P), 40 batches of methamphetamine hydrochloride were synthesized by the Leuckart and reductive amination methods (20 batches per method). Both basic and acidic impurities were extracted separately and analyzed by GC/MS. From this controlled study, two route specific impurities for the Leuckart method and one route specific impurity for the reductive amination method are reported. The intra- and inter-batch variation of these route specific impurities was assessed. Also, the variation of the "target impurities" recently recommended for methamphetamine profiling is discussed in relation to their variation within and between production batches synthesized using the Leuckart and reductive amination routes. PMID:19637924

  13. Asymmetric Imine Isomerisation in the Enantioselective Synthesis of Chiral Amines from Prochiral Ketones

    NARCIS (Netherlands)

    Willems, Johannes G.H.; Vries, Johannes G. de; Nolte, Roeland J.M.; Zwanenburg, Binne

    1995-01-01

    An asymmetric catalytic synthesis of chiral amines using a chiral base catalysed [1,3]-proton shift reaction of imines is described. The isomerisation reaction of N-benzylimines derived from prochiral ketones (benzylacetone, acetophenone) and p-substituted benzylamines, is catalysed by chiral alcoho

  14. Electrical detection of amine ligation to a metalloporphyrin via a hybrid SOI-MOSFET.

    Science.gov (United States)

    Takulapalli, Bharath R; Laws, Gez M; Liddell, Paul A; Andréasson, Joakim; Erno, Zach; Gust, Devens; Thornton, Trevor J

    2008-02-20

    A close-packed monolayer of zinc 5,10,15,20-tetrakis(3-carboxyphenyl)porphyrin has been prepared and deposited on the thin native oxide covering the surface of an SOI-MOSFET (silicon-on-insulator metal-oxide-semiconductor field effect transistor) using Langmuir-Blodgett techniques. When the device is exposed to amine vapors in a nitrogen atmosphere, the amine coordinates to the zinc atom. The resulting change in electron distribution within the porphyrin leads to a large change in the drain current of the transistor, biased via a back gate. This change is sensitive to both the amount of amine present and the base strength of the amine. Only very small changes in drain current were observed with a monolayer of free base porphyrin or palmitic acid. After exposure to high pyridine concentrations, the device response saturates, but partially recovers after overnight exposure to flowing nitrogen gas. Interestingly, the device response is instantaneously reset by exposure to visible light, suggesting that photode-ligation occurs. An electrical model for the hybrid device that describes its response to ligand binding in terms of a change in the work function of the porphyrin monolayer has been developed. A transistor response to a few hundred attomoles of bound pyridine can be readily detected. This extreme sensitivity, coupled with the ability to reset the device using light, suggests that such systems might be useful as sensors. PMID:18225896

  15. Properties of epoxy-amine networks containing nanostructured ether-crosslinked domains

    International Nuclear Information System (INIS)

    Highlights: ► The epoxy-amine networks with nanostructured ether-crosslinked domains (NECDs) was obtained. ► The morphology of the networks dispersed with 10–30-nm-sized NECDs was investigated by AFM. ► The molecular-level cavity in the matrix was inferred by a molecular-size simulation. ► The fracture toughness of the networks were reinforced up to 1.35 times that of neat epoxy. ► The networks were more thermostable than the neat epoxy because of higher cross-linking. - Abstract: Epoxy-amine networks with a nanodomain toughener—soft nanostructured ether-crosslinked domains (NECDs), which could increase the fracture and tensile toughness of the networks, were simply obtained when a mixture of diglycidyl ether bisphenol A (DGEBA) epoxy resin and 4,4′-methylene dianiline (MDA) hardener was heat-cured in the presence of varying amounts of the imidazole derivatives (called imidazoles)—1-methylimidazole (1-MI) or 2-methylimidazole (2-MI). Under these conditions, the epoxide groups in DGEBA underwent not only polyaddition with the aromatic amine of the MDA to form a hard epoxy-amine networked matrix but also anionic ring-opening polymerization by itself to build soft NECDs connected to the epoxy-amine matrix. The curing chemistry of the DGEBA/MDA mixture, both with and without the imidazoles, was studied using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The morphology of the networks dispersed with 5–30-nm-sized NECDs was investigated by atomic force microscopy (AFM). When the optimum amount (∼0.15–0.30 wt%) of imidazoles was added, the NECDs were effective in significantly increasing the tensile and fracture toughness and the thermal stability of the epoxy-amine networks without markedly sacrificing the glass transition temperature (Tg). The novel toughening mechanism and thermal behavior of the epoxy-amine networks were discussed.

  16. Properties of epoxy-amine networks containing nanostructured ether-crosslinked domains

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Ying-Gev, E-mail: yhsu@mail.ntust.edu.tw [Department of Material Science and Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); Lin, Kuan-Hung; Lin, Tse-Yu; Fang, Yi-Lung [Department of Material Science and Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); Chen, Su-Chen; Sung, Yi-Ching [Department of Raw Materials and Yarns, Taiwan Textile Research Institute, New Taipei, Taiwan (China)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer The epoxy-amine networks with nanostructured ether-crosslinked domains (NECDs) was obtained. Black-Right-Pointing-Pointer The morphology of the networks dispersed with 10-30-nm-sized NECDs was investigated by AFM. Black-Right-Pointing-Pointer The molecular-level cavity in the matrix was inferred by a molecular-size simulation. Black-Right-Pointing-Pointer The fracture toughness of the networks were reinforced up to 1.35 times that of neat epoxy. Black-Right-Pointing-Pointer The networks were more thermostable than the neat epoxy because of higher cross-linking. - Abstract: Epoxy-amine networks with a nanodomain toughener-soft nanostructured ether-crosslinked domains (NECDs), which could increase the fracture and tensile toughness of the networks, were simply obtained when a mixture of diglycidyl ether bisphenol A (DGEBA) epoxy resin and 4,4 Prime -methylene dianiline (MDA) hardener was heat-cured in the presence of varying amounts of the imidazole derivatives (called imidazoles)-1-methylimidazole (1-MI) or 2-methylimidazole (2-MI). Under these conditions, the epoxide groups in DGEBA underwent not only polyaddition with the aromatic amine of the MDA to form a hard epoxy-amine networked matrix but also anionic ring-opening polymerization by itself to build soft NECDs connected to the epoxy-amine matrix. The curing chemistry of the DGEBA/MDA mixture, both with and without the imidazoles, was studied using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The morphology of the networks dispersed with 5-30-nm-sized NECDs was investigated by atomic force microscopy (AFM). When the optimum amount ({approx}0.15-0.30 wt%) of imidazoles was added, the NECDs were effective in significantly increasing the tensile and fracture toughness and the thermal stability of the epoxy-amine networks without markedly sacrificing the glass transition temperature (T{sub g}). The novel toughening mechanism and

  17. Bioactive amines in Brazilian wines: types, levels and correlation with physico-chemical parameters

    Directory of Open Access Journals (Sweden)

    Solange C. Souza

    2005-01-01

    Full Text Available The levels of ten bioactive amines and the physico-chemical characteristics of Cabernet Sauvignon, Cabernet Franc and Merlot wines from Bento Gonçalves, RS, Brazil, vintage of 1999 were investigated. The physico-chemical characteristics varied significantly: pH from 3.80 to 4.07, total acidity from 67.7 to 85.3 meq/L, alcohol content from 11.45 to 12.46 mL/100 mL and total SO2 from 9.6 to 102 mg/L. Six amines were detected in every sample - spermidine, putrescine, histamine, tyramine, serotonine and phenylethylamine. Total amine levels ranged from 2.03 to 7.60 mg/L. Putrescine was the prevalent amine, contributing with 20 to 66% of total levels. The amine profile and total levels were affected to a greater extent by vinification practices compared to grape type. There was significant correlation between some amines and also between amines and the physico-chemical parameters. Histamine levels were well below limits recommended by several countries.Os teores de aminas bioativas e as características físico-químicas de Cabernet Sauvignon, Cabernet Franc e Merlot da região de Bento Gonçalves, RS, safra de 1999, foram analisados. As características físico-químicas variaram significativamente: pH de 3,80 a 4,07; acidez total de 67,7 a 85,3 meq/L, teor alcoólico de 11,45 a 12,46 mL/100 mL e SO2 total de 9,6 a 102 mg/L. Seis aminas estavam presentes em todas as amostras - espermidina, putrescina, histamina, tiramina, serotonina e feniletilamina. Os teores totais de aminas variaram de 2,03 a 7,60 mg/L. Putrescina foi a amina predominante, contribuindo com 20 a 66% do total. O perfil de aminas foi mais afetado pela vinícola do que pelo tipo de uva. Houve correlação significativa entre aminas e também entre aminas e parâmetros físico-químicos. Os teores de histamina detectados são inferiores aos limites máximos estipulados para o vinho em outros países.

  18. Plant and Soil Emissions of Amines and Amino Acids: A Source of Secondary Aerosol Precursors

    Science.gov (United States)

    Jackson, M. L.; Doskey, P. V.; Pypker, T. G.

    2011-12-01

    Ammonia (NH3) is the most abundant alkaline gas in the atmosphere and forms secondary aerosol by neutralizing sulfuric and nitric acids that are released during combustion of fossil fuels. Ammonia is primarily emitted by cropping and livestock operations. However, C2 and C3 amines (pKb 3.3-3.4), which are stronger bases than NH3 (pKb 4.7) have been observed in nuclei mode aerosol that is the precursor to secondary aerosol. Mixtures of amines and amino acids have been identified in diverse environments in aerosol, fog water, cloud water, the soluble fraction of precipitation, and in dew. Glycine (pKb 4.2), serine (pKb 4.8) and alanine (pKb 3.7 and 4.1 for the D and L forms, respectively) are typically the most abundant species. The only reported values of gas-phase glycine, serine and alanine were in marine air and ranged from 6-14 pptv. The origin of atmospheric amines and amino acids has not been fully identified, although sources are likely similar to NH3. Nitrate assimilation in plants forms glycine, serine, and L-alanine, while D-alanine is present in bacterial cell walls. Glycine is converted to serine during C3 plant photorespiration, producing CO2 and NH3. Bacteria metabolize glycine and alanine to methylamine and ethylamine via decarboxylation. Likely sources of amino acids are plants and bacteria, thus concentrations near continental sources are likely greater than those measured in marine air. The overall goal of the research is to examine seasonal variations and relationships between the exchange of CO2, NH3, amines, and amino acids with a corn/soybean rotation in the Midwest Corn Belt. The study presents gaseous profiles of organic amine compounds from various species of vegetation using a mist chamber trapping technique and analysis of the derivatized species by high pressure liquid chromatography with fluorescence detection. Amino acid and amine profiles were obtained for red oak (Quercus rubra), sugar maple (Acer saccharinum), white pine (Pinus

  19. Emission of Trimethylamine from Chenopodium vulvaria - first results from quantifiying plant emissions of amines

    Science.gov (United States)

    Sun, Shang; Neftel, Albrecht; Jörg, Sintermann; Derstroff, Bettina; Sauvage, Carina; Bohley, Katharina; Kadereit, Gudrun; Williams, Jonathan; Pöhlker, Christopher; Kesselmeier, Jürgen; Sörgel, Matthias

    2016-04-01

    Amines comprise a wide range of nitrogenous organic compounds such as aliphatic methylamines MA. TMA is the most common amine species emitted by various sources and the most abundant amine in the atmosphere (Ge et al., 2011a). Additionally, TMA has been found to be the dominant amine species in the gas-phase compared to MMA and DMA at agriculture sites (Schade and Crutzen, 1995). On the global scale, the knowledge about the fluxes of most amines is limited (Ge et al., 2011a). Furthermore, terrestrial vegetation is also assumed to be a potential source for amines (Schade and Crutzen, 1995). There are a few studies from the end of the 19th century until 1975, which described high amount of MA-emission from certain plant species, which was associated with their plant tissues or with blossoms during flowering (Smith, 1971). Despite the low atmospheric concentration of amines (DMA = 0.5 ppb (Okita, 1970), TMA = 0.6 -1.6 ppb (Fujii and Kitai, 1987)), previous studies have already shown that amines play an important role in the New aerosol Particle Formation (NPF) (Almeida et al., 2013, and summarized in Sintermann and Neftel, 2015). In the atmosphere, NPF occurs frequently from gas-phase precursors. High uncertainty exists in the estimation of the global secondary aerosols budget, which was cause to the uncertain contribution of the gas-phase precursors to the NPF (Spracklen et al., 2011). It becomes more clearly that instead of binary systems of sulfuric acid and water, ternary system of sulfuric acid, water and a neutralizing compound as NH3 or amines is a key system in NPF (Almeida et al., 2013, Kurten et al., 2014). Despite their low atmospheric concentrations amines may play, at least locally, a crucial role in aerosol formation. In this study, we focus on the plant species chenopodium vulvaria, which is well known as a strong TMA-emitter (Dessaignes, 1856). But TMA emission rates from that plant species was not determined systematically up to now. In this study, we

  20. Structure, Function, and Evolution of Biogenic Amine-binding Proteins in Soft Ticks

    Energy Technology Data Exchange (ETDEWEB)

    Mans, Ben J.; Ribeiro, Jose M.C.; Andersen, John F. (NIH)

    2008-08-19

    Two highly abundant lipocalins, monomine and monotonin, have been isolated from the salivary gland of the soft tick Argas monolakensis and shown to bind histamine and 5-hydroxytryptamine (5-HT), respectively. The crystal structures of monomine and a paralog of monotonin were determined in the presence of ligands to compare the determinants of ligand binding. Both the structures and binding measurements indicate that the proteins have a single binding site rather than the two sites previously described for the female-specific histamine-binding protein (FS-HBP), the histamine-binding lipocalin of the tick Rhipicephalus appendiculatus. The binding sites of monomine and monotonin are similar to the lower, low affinity site of FS-HBP. The interaction of the protein with the aliphatic amine group of the ligand is very similar for the all of the proteins, whereas specificity is determined by interactions with the aromatic portion of the ligand. Interestingly, protein interaction with the imidazole ring of histamine differs significantly between the low affinity binding site of FS-HBP and monomine, suggesting that histamine binding has evolved independently in the two lineages. From the conserved features of these proteins, a tick lipocalin biogenic amine-binding motif could be derived that was used to predict biogenic amine-binding function in other tick lipocalins. Heterologous expression of genes from salivary gland libraries led to the discovery of biogenic amine-binding proteins in soft (Ornithodoros) and hard (Ixodes) tick genera. The data generated were used to reconstruct the most probable evolutionary pathway for the evolution of biogenic amine-binding in tick lipocalins.

  1. CO2 adsorption properties of char produced from brown coal impregnated with alcohol amine solutions.

    Science.gov (United States)

    Baran, Paweł; Zarębska, Katarzyna; Czuma, Natalia

    2016-07-01

    Carbon dioxide (CO2) emission reduction is critical to mitigating climate change. Power plants for heating and industry are significant sources of CO2 emissions. There is a need for identifying and developing new, efficient methods to reduce CO2 emissions. One of the methods used is flue gas purification by CO2 capture through adsorption. This study aimed to develop CO2 adsorbent out of modified brown coal impregnated with solutions of first-, second-, and third-order amines. Low-temperature nitrogen adsorption isotherms and CO2 isotherms were measured for the prepared samples. The results of experiments unexpectedly revealed that CO2 sorption capacity decreased after impregnation. Due to lack of strait trends in CO2 sorption capacity decrease, the results were closely analyzed to find the reason for the inconsistencies. It was revealed that different amines represent different affinities for CO2 and that the size and structure of impregnating factor has influence on the CO2 sorption capacity of impregnated material. The character of a support was also noticeable as well for impregnation results as for the affinity to CO2. The influence of amine concentration used was investigated along with the comparison on how the theoretical percentage of the impregnation on the support influenced the results. The reaction mechanism of tertiary amine was taken into consideration in connection to no presence of water vapor during the experiments. Key findings were described in the work and provide a strong basis for further studies on CO2 adsorption on amine-impregnated support. PMID:27317051

  2. Occurrence of selected aliphatic amines in source water of major cities in China

    Institute of Scientific and Technical Information of China (English)

    Haifeng Zhang; Shuoyi Ren; Jianwei Yu; Min Yang

    2012-01-01

    The formation of toxic nitrogenous disinfection byproducts (N-DBPs),such as nitrosamines,halonitromethanes and haloacetonitriles,from reactions between chlorine/chloramine and dissolved organic nitrogen in drinking water has caused great concern with regarding public health.This study revealed the occurrence of 17 aliphatic amines,some of which have been confirmed to be the precursors of N-DBPs,in source water across China.A sensitive method based on benzenesulfonyl chloride derivatization and liquid-liquid extraction followed by GC-MS analysis was established for the simultaneous analysis of the selected amines in aqueous samples.In total,37 source water samples from the capital cities of 20 provinces were collected for the survey.Among the 17 amines,14 were detected with an average frequency of detection of 36%.The most relevant amines in terms of frequency and maximum concentrations detected were dimethylamine (100%,24.82 μg/L),methylamine (78%,0.92 μg/L),N-methylethylamine (70%,8.84 μg/L),propylamine (59%,10.69 μg/L),diethylamine (54%,3.76 μg/L),N-methylbutylamine (35%,3.07 μg/L),N-ethylpropylamine (35%,0.52 μg/L),and piperidine (32%,2.35 μg/L).This is the first large scale survey of the aliphatic amines occurrence in source water in the world.The wide presence of nitrosamine precursors like dimethylamine,N-methylethylamine and diethylamine,and the precursors of haloacetonitriles and halonitromethanes like methylamine and propylamine suggests that better source water management is required to ensure the safety of drinking water.

  3. Uncertainties in assessing the environmental impact of amine emissions from a CO2 capture plant

    Directory of Open Access Journals (Sweden)

    M. Karl

    2014-08-01

    Full Text Available In this study, a new model framework that couples the atmospheric chemistry transport model system Weather Research and Forecasting–European Monitoring and Evaluation Programme (WRF-EMEP and the multimedia fugacity level III model was used to assess the environmental impact of in-air amine emissions from post-combustion carbon dioxide capture. The modelling framework was applied to a typical carbon capture plant artificially placed at Mongstad, on the west coast of Norway. The study region is characterized by high precipitation amounts, relatively few sunshine hours, predominantly westerly winds from the North Atlantic and complex topography. Mongstad can be considered as moderately polluted due to refinery activities. WRF-EMEP enables a detailed treatment of amine chemistry in addition to atmospheric transport and deposition. Deposition fluxes of WRF-EMEP simulations were used as input to the fugacity model in order to derive concentrations of nitramines and nitrosamine in lake water. Predicted concentrations of nitramines and nitrosamines in ground-level air and drinking water were found to be highly sensitive to the description of amine chemistry, especially of the night-time chemistry with the nitrate (NO3 radical. Sensitivity analysis of the fugacity model indicates that catchment characteristics and chemical degradation rates in soil and water are among the important factors controlling the fate of these compounds in lake water. The study shows that realistic emission of commonly used amines result in levels of the sum of nitrosamines and nitramines in ground-level air (0.6–10 pg m−3 and drinking water (0.04–0.25 ng L−1 below the current safety guideline for human health that is enforced by the Norwegian Environment Agency. The modelling framework developed in this study can be used to evaluate possible environmental impacts of emissions of amines from post-combustion capture in other regions of the world.

  4. Reactions of Methanesulfonic Acid with Amines and Ammonia as a Source of New Particles in Air.

    Science.gov (United States)

    Chen, Haihan; Varner, Mychel E; Gerber, R Benny; Finlayson-Pitts, Barbara J

    2016-03-01

    New particle formation (NPF) from gaseous precursors as a significant source of aerosol needs to be better understood to accurately predict the impacts on visibility, climate change, and human health. While ternary nucleation of sulfuric acid, amines/NH3, and water is recognized as a significant driver for NPF, increasing evidence suggests a contribution from methanesulfonic acid (MSA) and amines under certain conditions. Here we report the formation of particles 2.5-10 nm in diameter from the reactions of MSA with methylamine (MA), dimethylamine (DMA), and NH3 at reaction times of 2.3-7.8 s in a flow reactor and compare these particles with those previously reported to be formed from reaction with trimethylamine (TMA). The effects of water vapor and concentrations of gaseous precursors on the particle number concentration and particle size were studied. The presence of water significantly enhances particle formation and growth. Under similar experimental conditions, particle number concentrations decrease in the order MA ≫ TMA ≈ DMA ≫ NH3, where NH3 is 2-3 orders of magnitude less efficient than DMA. Quantum chemical calculations of likely intermediate clusters were carried out to provide insights into the role of water and the different capacities of amines/NH3 in particle formation. Both gas-phase basicity and hydrogen-bonding capacity of amines/NH3 contribute to the potential for particles to form and grow. Our results indicate that, although amines typically have concentrations 1-3 orders of magnitude lower than that of NH3 in the atmosphere, they still play an important role in driving NPF. PMID:26379061

  5. Kinetics and mechanism of bimolecular electron transfer reaction in quinone-amine systems in micellar solution

    International Nuclear Information System (INIS)

    Photoinduced electron transfer (ET) reactions between anthraquinone derivatives and aromatic amines have been investigated in sodium dodecyl sulphate (SDS) micellar solutions. Significant static quenching of the quinone fluorescence due to high amine concentration in the micellar phase has been observed in steady-state measurements. The bimolecular rate constants for the dynamic quenching in the present systems kqTR, as estimated from the time-resolved measurements, have been correlated with the free energy changes ΔG0 for the ET reactions. Interestingly it is seen that the kqTR vs ΔG0 plot displays an inversion behavior with maximum kqTR at around 0.7 eV, a trend similar to that predicted in Marcus ET theory. Like the present results, Marcus inversion in the kqTR values was also observed earlier in coumarin-amine systems in SDS and TX-100 micellar solutions, with maximum kqTR at around the same exergonicity. These results thus suggest that Marcus inversion in bimolecular ET reaction is a general phenomenon in micellar media. Present observations have been rationalized on the basis of the two-dimensional ET (2DET) theory, which seems to be more suitable for micellar ET reactions than the conventional ET theory. For the quinone-amine systems, it is interestingly seen that kqTR vs ΔG0 plot is somewhat wider in comparison to that of the coumarin-amine systems, even though the maxima in the kqTR vs ΔG0 plots appear at almost similar exergonicity for both the acceptor-donor systems. These observations have been rationalized on the basis of the differences in the reaction windows along the solvation axis, as envisaged within the framework of the 2DET theory, and arise due to the differences in the locations of the quinones and coumarin dyes in the micellar phase

  6. Development of efficient amine-modified mesoporous silica SBA-15 for CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaoyun; Qin, Hongyan; Zheng, Xiuxin; Wu, Wei, E-mail: wuweiupc@upc.edu.cn

    2013-10-15

    Graphical abstract: - Highlights: • A secondary amine AN-TEPA is used to modify the SBA-15. • CO{sub 2} adsorption capacity (180.1 mg g{sup −1}-adsorbent for 70% amine loading) is high. • The sorbent exhibits a high stability after 12 cycling runs. • The modified SBA-15 achieves complete desorption at low temperature (100 °C). - Abstract: A novel CO{sub 2} sorbent was prepared by impregnating mesoporous silica, SBA-15, with acrylonitrile (AN)-modified tetraethylenepentamine (TEPA) in order to increase CO{sub 2} adsorption capacity and improve cycling stability. The mesoporous silica with pre- and post-surface modification was investigated by X-ray diffraction characterization (XRD), N{sub 2} adsorption–desorption test (N{sub 2}-BET), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). The adsorption/desorption performance of S-TN (TN: AN modified TEPA) and S-TEPA was studied by dynamic adsorption. Test results showed that the solid base-impregnated SBA-15 demonstrated high CO{sub 2} adsorption capacity (180.1 mg g{sup −1}-adsorbent for 70% amine loading level). Compared to S-TEPA (24.1% decrease of initial capacity), S-TN with 50% amine loading exhibited improved cycling stability, 99.9% activity reserved (from initial 153.0 mg g{sup −1} to 151.3 mg g{sup −1}) after 12 cycles of adsorption/desorption at 100 °C. A mechanism of molecular structure of the loaded amine was attributed to the improved performance.

  7. Amine functionalized radiation-induced grafted water hyacinth fibers for Pb2+, Cu2+ and Cr3+ uptake

    Science.gov (United States)

    Madrid, Jordan F.; Nuesca, Guillermo M.; Abad, Lucille V.

    2014-04-01

    An amine group containing fibrous adsorbent was prepared by reaction of grafted water hyacinth fibers with ethylenediamine. Glycidyl methacrylate (GMA) was grafted onto water hyacinth fibers using gamma radiation induced graft polymerization through simultaneous grafting technique and this was used as base material for producing the amine type adsorbents. The conversion of the epoxy group from GMA into amine group was investigated. The concentration of ethylenediamine solution that gave the highest amine functional group density was 50% by volume in 2-propanol. The amine functionalized water hyacinth fibers were characterized using Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscopy (ATR-FTIR), Thermogravimetric Analysis (TGA), and Energy Dispersive X-ray Spectroscopy (EDX). Information derived from these analyses confirms the successful conversion of the epoxy group. The amine-type adsorbent was evaluated for its uptake of Pb2+, Cu2+ and Cr3+ from aqueous solutions. The initial concentration of the metal ions and pH of the solutions were found to influence the amount of metal ions adsorbed by the amine-type adsorbent. The kinetics of adsorption was observed to follow Lagergren's first order equation. Results of ion sorption studies indicate that gamma radiation-induced grafting and subsequent chemical modification improved the ion sorption behaviour of water hyacinth fibers.

  8. Impact of biogenic amine molecular weight and structure on surfactant adsorption at the air-water interface.

    Science.gov (United States)

    Penfold, Jeffrey; Thomas, Robert K; Li, Peixun

    2016-02-01

    The oligoamines, such as ethylenediamine to pentaethylenetetramine, and the aliphatic biogenic amines, such as putrescine, spermidine and spermine, strongly interact with anionic surfactants, such as sodium dodecylsulfate, SDS. It has been shown that this results in pronounced surfactant adsorption at the air-water interface and the transition from monolayer to multilayer adsorption which depends upon solution pH and oligoamine structure. In the neutron reflectivity, NR, and surface tension, ST, results presented here the role of the oligoamine structure on the adsorption of SDS is investigated more fully using a range of different biogenic amines. The effect of the extent of the intra-molecular spacing between amine groups on the adsorption has been extended by comparing results for cadavarine with putrescine and ethylenediamine. The impact of more complex biogenic amine structures on the adsorption has been investigated with the aromatic phenethylamine, and the heterocyclic amines histamine and melamine. The results provide an important insight into how surfactant adsorption at interfaces can be manipulated by the addition of biogenic amines, and into the role of solution pH and oligoamine structure in modifying the interaction between the surfactant and oligoamine. The results impact greatly upon potential applications and in understanding some of the important biological functions of biogenic amines. PMID:26524255

  9. Amine functionalized radiation-induced grafted water hyacinth fibers for Pb2+, Cu2+ and Cr3+ uptake

    International Nuclear Information System (INIS)

    An amine group containing fibrous adsorbent was prepared by reaction of grafted water hyacinth fibers with ethylenediamine. Glycidyl methacrylate (GMA) was grafted onto water hyacinth fibers using gamma radiation induced graft polymerization through simultaneous grafting technique and this was used as base material for producing the amine type adsorbents. The conversion of the epoxy group from GMA into amine group was investigated. The concentration of ethylenediamine solution that gave the highest amine functional group density was 50% by volume in 2-propanol. The amine functionalized water hyacinth fibers were characterized using Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscopy (ATR-FTIR), Thermogravimetric Analysis (TGA), and Energy Dispersive X-ray Spectroscopy(EDX). Information derived from these analyses confirms the successful conversion of the epoxy group. The amine type adsorbent was evaluated for its uptake of Pb2+, Cu2+ and Cr3+ from aqueous solutions. The initial concentration of the metal ions and pH of the solutions were found to influence the amount of metal ions adsorbed by the amine-type adsorbent. The kinetics of adsorption was observed to follow Lagergen's first order equation. Results of ion sorption studies indicate that gamma radiation-induced grafting and subsequent chemical modification improved the ion sorption behaviour of water hyacinth fibers. (Author)

  10. Degradation of aromatic amines in textile-dyeing sludge by combining the ultrasound technique with potassium permanganate treatment.

    Science.gov (United States)

    Liang, Jieying; Ning, Xun-An; An, Taicheng; Sun, Jian; Zhang, Yaping; Wang, Yujie

    2016-08-15

    This paper reports, for the first time, a combined technique of ultrasound (US) with KMnO4 degradation of aromatic amines in a textile-dyeing sludge. The reaction mechanisms and the degradation kinetics of aromatic amines at various operating parameters (KMnO4 dosage, US power density and pH) were systematically examined by the combined system of US-KMnO4. The results indicated that there was a synergistic effect between US and KMnO4, as US greatly enhanced KMnO4 in the degradation of aromatic amines and exhibited apparent sludge disintegration and separated pollutants from the sludge. In addition to accelerating the Mn(VII) reaction with pollutants in the filtrate, US also caused Mn(VII) to enter the porous sludge and sufficiently facilitated the reaction of the strongly absorbed aromatic amines. The combined treatment of US-KMnO4 was effective in the degradation of aromatic amines in textile-dyeing sludge. On average, 58.7% of monocyclic anilines, 88.3% of other forms of aromatic amines, and 24.0% of TOC were removed under the optimal operating conditions of a KMnO4 dosage of 12mM, an US power density of 1.80W/cm(3) and pH 5. The present study proposed US-KMnO4 treatment as a practical method for the disposal of aromatic amines in textile-dyeing sludge. PMID:27107230

  11. Neighboring Hetero-Atom Assistance of Sacrificial Amines to Hydrogen Evolution Using Pt-Loaded TiO2-Photocatalyst

    OpenAIRE

    Masahide Yasuda; Takayuki Tomo; Shoichi Hirata; Tsutomu Shiragami; Tomoko Matsumoto

    2014-01-01

    Photocatalytic H2 evolution was examined using Pt-loaded TiO2-photocatalyst in the presence of amines as sacrificial agents. In the case of amines with all of the carbon attached to the hetero-atom such as 2-aminoethanol, 1,2-diamonoethane, 2-amino-1,3-propanediol, and 3-amino-1,2-propanediol, they were completely decomposed into CO2 and water to quantitatively evolve H2. On the other hand, the amines with both hetero-atoms and one methyl group at the β-positions (neighboring carbons) of ami...

  12. Structures, Metal Ion Affinities, and Fluorescence Properties of Soluble Derivatives of Tris((6-phenyl-2-pyridyl)methyl)amine

    OpenAIRE

    Liang, Jian; Zhang, Jing; Zhu, Lei; Duarandin, Alexander; Young, Victor G.; Geacintov, Nicholas; Canary, James W.

    2009-01-01

    Metal complexes of tris((6-phenyl-2-pyridyl)methyl)amine (2) have hydrophobic cavities that potentially accommodate small molecules. However, the utility of this attractive motif has been hampered by the poor solubility of such complexes in many common solvents. In this study, two tripodal ligands (3, tris-[6-(3,4,5-trimethoxy-phenyl)-pyridin-2-ylmethyl]-amine, and 4, tris((6-(3,4,5-tris(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)phenyl)pyridin-2-yl)methyl)amine) derived from 2 were prepared with en...

  13. Effect of pH and modifier-concentration on the solvent extraction of molybdenum with an alkyl amine

    International Nuclear Information System (INIS)

    The results of the extraction behaviour of molybdenum in aqueous sulfuric acid solutions of an alkyl amine (amberlite LA-2) in kerosene under various pH and in the presence of various percentage of 1-octanol has been reported. The concentration of molybdenum employed was high enough to precipitate it partially during extraction as an amine-molybdenum complex. The maximum extraction coefficient was found to lie between pH 1.5-2.5. Presence of 1-octanol increased the extraction coefficient of molybdenum by increasing the solubility of the amine-molybdenum complex in the organic phase without changing the pH at the maximum extraction. (Auth.)

  14. Carbohydrate-interactive pDNA and siRNA gene vectors based on boronic acid functionalized poly(amido amine)s.

    Science.gov (United States)

    Piest, Martin; Ankoné, Marc; Engbersen, Johan F J

    2013-08-10

    In order to evaluate the influence of incorporation of boronic acid groups on the properties of poly(amido amine)s as gene vectors, a novel poly(amido amine) copolymer p(CBA-ABOL/2AMPBA) containing ortho-aminomethylphenylboronic acid (2AMPBA) moieties was prepared by Michael-type polyaddition of a mixture of 1,4-aminobutanol (ABOL) and 2-((4-aminobutylamino)methyl)phenyl boronic acid to N,N'-cystamine bisacrylamide (CBA). It appeared that the presence of the boronic acid moieties as side groups along the polymer chain strongly enhances the stability of the self-assembled nanoparticles and nanosized polyplexes formed from this polymer; no aggregation was observed after storage for 6days at 37°C. This strong stabilization can be attributed to intermolecular Lewis acid-base interactions between the 2AMPBA groups and the alcohol and amine groups present in the polymer, leading to dynamical (reversible) crosslinking in the nanoparticles. Moreover, since the boronic acids can reversibly form boronic esters with vicinal diol groups, the presence of the 2AMPBA groups add carbohydrate-interactive properties to these polymers that strongly influence their behavior as gene delivery vectors. DNA transfection with p(CBA-ABOL/2AMPBA) polyplexes gave transfection efficiencies that were approximately similar to commercial PEI in different cell lines (COS-7, HUH-6 and H1299-Fluc), but lower than those obtained with reference polyplexes from p(CBA-ABOL). It is hypothesized that the uptake of the boronated polyplexes is suppressed by binding to the glycocalyx of the cells. This is supported by the observation that addition of sorbitol or dextran to the transfection medium significantly enhances the transfection efficiency, which can be attributed to increased cellular uptake of the polyplexes due to boronic ester formation with these agents. AFM, SEM and confocal microscopy showed that polyplexes of p(CBA-ABOL/2AMPBA) become decorated with a dextran layer in the presence of 0.9% (w

  15. Production of amines in equine cecal contents in an in vitro model of carbohydrate overload.

    Science.gov (United States)

    Bailey, S R; Rycroft, A; Elliott, J

    2002-10-01

    Acute laminitis can be induced experimentally in horses by the administration of carbohydrate, resulting in fermentation within the cecum and ischemia-reperfusion of the digits. The products of fermentation that trigger acute laminitis are as yet unknown; however, compounds such as amines might play a role due to their potential vasoactive properties. The objectives of this study were to quantify the amines present in equine cecal contents and to use a model of carbohydrate overload in vitro to test the hypothesis that carbohydrate fermentation is associated with increased amine production. Cecal contents from each horse were divided into aliquots and incubated anaerobically with either cornstarch or inulin (a form of fructan carbohydrate; both 1 g/100 mL). The pH was measured and samples were taken at the same time for amine measurement by HPLC at 2-h intervals over a 24-h period. In a second set of experiments, the effects of the antibiotic virginiamycin (1 mg/100 mL), calcium (CaPO4; 0.3 g/100 mL), and plant steroidal saponin (Yucca schidigera extract; 0.1 g/100 mL) were examined on pH and amine concentrations in cecal contents incubated with starch or inulin. Both starch and inulin caused significant time-dependent falls in pH, from 6.7 +/- 0.1 at 0 h to 5.2 +/- 0.1 (starch) and 5.0 +/- 0.1 (inulin) at 24 h. Fermentation of carbohydrate was also associated with increased production of phenylethylamine and isoamylamine (two- to threefold increases) as well as putrescine and cadaverine (1.5- to twofold increases). Virginiamycin inhibited the fall in pH and increases in production of phenylethylamine and isoamylamine, while calcium phosphate moderated the changes in pH only. Yucca schidigera extract was without effect. These data show that fermentation of carbohydrate by equine cecal microbiota may lead to increased production of amines. PMID:12413088

  16. Reactions of hypochlorous acid with biological substrates are activated catalytically by tertiary amines.

    Science.gov (United States)

    Prütz, W A

    1998-09-15

    The activation of reactions of HOCl with a variety of model substrates by tertiary amines was investigated spectroscopically by tandem-mix and stopped-flow techniques. HOCl-induced chlorination of salicylate can be sped up by several orders of magnitude by catalytic amounts of trimethylamine (TMN). The effect is obviously due to the fast generation of reactive quarternary chloramonium ions, TMN+ Cl, which act as chain carrier in a catalytic reaction cycle. Of various catalysts tested, quinine shows the highest activity; this is attributable to the quinuclidine (QN) substituent, a bicyclic tertiary amine, forming a particularly reactive chloro derivative, QN+ Cl, which does not decompose autocatalytically. The rate of catalytic salicylate chlorination as a function of pH (around pH 7) depends not at least on the basicity of the tertiary amine; the rate increases with pH in the cases of TMN and quinuclidine (high basicity), but decreases with pH in the case of MES (low basicity). Tertiary amines also catalyze the interaction between HOCl and alkenes, as shown using sorbate as model. Reaction of HOCl with the nucleotides GMP and CMP is sped up remarkably by catalytic amounts of tertiary amines. In the case of GMP the same product spectrum is produced by HOCl in absence and presence of catalyst, but a change in the product spectra is obtained when AMP and CMP are reacted with HOCl in presence of catalyst. Using poly(dA-dT).poly(dA-dT) as DNA model, it is shown that HOCl primarily induces an absorbance increase at 263 nm, which indicates unfolding of the double strand due to fast chlorination of thymidine; a subsequent secondary absorbance decrease can be explained by slow chlorination of adenosine. Both the primary and secondary processes are activated by catalytic amounts of quinine. No evidence was found for a radical pathway in TMN-mediated oxidation of formate by HOCl. The present results suggest that low concentrations of certain tertiary amines have the potential

  17. Chemical reactivity of graphene oxide towards amines elucidated by solid-state NMR

    Science.gov (United States)

    Vacchi, Isabella A.; Spinato, Cinzia; Raya, Jésus; Bianco, Alberto; Ménard-Moyon, Cécilia

    2016-07-01

    Graphene oxide (GO) is an attractive nanomaterial for many applications. Controlling the functionalization of GO is essential for the design of graphene-based conjugates with novel properties. But, the chemical composition of GO has not been fully elucidated yet. Due to the high reactivity of the oxygenated moieties, mainly epoxy, hydroxyl and carboxyl groups, several derivatization reactions may occur concomitantly. The reactivity of GO with amine derivatives has been exploited in the literature to design graphene-based conjugates, mainly through amidation. However, in this study we undoubtedly demonstrate using magic angle spinning (MAS) solid-state NMR that the reaction between GO and amine functions occurs via ring opening of the epoxides, and not by amidation. We also prove that there is a negligible amount of carboxylic acid groups in two GO samples obtained by a different synthesis process, hence eliminating the possibility of amidation reactions with amine derivatives. This work brings additional insights into the chemical reactivity of GO, which is fundamental to control its functionalization, and highlights the major role of MAS NMR spectroscopy for a comprehensive characterization of derivatized GO.Graphene oxide (GO) is an attractive nanomaterial for many applications. Controlling the functionalization of GO is essential for the design of graphene-based conjugates with novel properties. But, the chemical composition of GO has not been fully elucidated yet. Due to the high reactivity of the oxygenated moieties, mainly epoxy, hydroxyl and carboxyl groups, several derivatization reactions may occur concomitantly. The reactivity of GO with amine derivatives has been exploited in the literature to design graphene-based conjugates, mainly through amidation. However, in this study we undoubtedly demonstrate using magic angle spinning (MAS) solid-state NMR that the reaction between GO and amine functions occurs via ring opening of the epoxides, and not by

  18. Novel hot-melting hyperbranched poly(ester-amine) bearing self-complementary quadruple hydrogen bonding units

    Institute of Scientific and Technical Information of China (English)

    Yi Peng Qiu; Li Ming Tang; Yu Wang; Shi You Guan

    2008-01-01

    Hyperbranched poly(amine-ester)s bearing serf-complementary quadruple hydrogen bonding units display excellent mechanical and temperature-dependent melt rheological properties,which make them suitable as novel hot-melting materials.

  19. A direct approach to amines with remote stereocentres by enantioselective CuH-catalysed reductive relay hydroamination

    Science.gov (United States)

    Zhu, Shaolin; Niljianskul, Nootaree; Buchwald, Stephen L.

    2016-02-01

    Amines with remote stereocentres (stereocentres that are three or more bonds away from the C-N bond) are important structural elements in many pharmaceutical agents and natural products. However, previously reported methods to prepare these compounds in an enantioselective manner are indirect and require multistep synthesis. Here, we report a copper-hydride-catalysed, enantioselective synthesis of γ- or δ-chiral amines from readily available allylic alcohols, esters and ethers using a reductive relay hydroamination strategy (a net reductive process in which an amino group is installed at a site remote from the original carbon-carbon double bond). The protocol was suitable for substrates containing a wide range of functional groups and provided remote chiral amine products with high levels of regio- and enantioselectivity. Sequential amination of substrates containing several carbon-carbon double bonds could be achieved, demonstrating the high chemoselectivity of this process.

  20. Synthesis and Structure of Zinc Complex of N, N-bis ( benzimidazol-2-yl-methyl ) amine

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Zinc complex of N, N-bis (benzimidazol-2-yl-methyl)amine has been synthesized and its crystal structure determined by X-ray diffraction method. The structure features of the complex are described.