WorldWideScience

Sample records for cyclamates

  1. Oxidation of hydrogen peroxide by [Ni III (cyclam)

    Indian Academy of Sciences (India)

    The kinetics of oxidation of H2O2 by [NiIII(cyclam)]3+, [NiIIIL1], was studied in aqueous acidic media at 25°C and I = 0.5M (NaClO4). The [NiIIIL1] to [NiIIL1] reduction was found to be fast in the presence of Cu(II) ion than the oxidation of the cyclam ligand by ·OH. The rate constant showed an inverse acid dependence on H+ ...

  2. 21 CFR 189.135 - Cyclamate and its derivatives.

    Science.gov (United States)

    2010-04-01

    ... Analytical Chemists,” 13th Ed. (1980), which is incorporated by reference. Copies may be obtained from the AOAC INTERNATIONAL, 481 North Frederick Ave., suite 500, Gaithersburg, MD 20877, or may be examined at... Register of October 21, 1969 (34 FR 17063). (c) The analytical methods used for detecting cyclamate in food...

  3. Determination of Cyclam as Impurity in 99mTc-CTMP Using Radio electrophoresis Method

    International Nuclear Information System (INIS)

    Isti Daruwati; Misyetti; Maula Eka Sriyani; Teguh Hafiz AW

    2009-01-01

    Labelled compound of CTMP that are used for bone seeking radiopharmaceuticals must have to fulfill the standard requirements, such as have high radiochemical purity. CTMP compounds was in house synthesized from cyclam and formaldehyde in an acidic condition (conc. HCl) using Mannich methods. Impurities in CTMP product are the residue of cyclam, phosphoric acid, formaldehyde and hydrochloric acid. Formaldehyde and hydrochloride acid in the aqueous form is easily removed through the rinse process in the synthesis, while cyclam in the solid phase could be mix with CTMP. Therefore the impurities of cyclam in 99m Tc-CTMP must be determined. With nuclear technique, the determination of cyclam could be assessed simultaneously with labelled of CTMP with technetium-99m. Separation of 99m Tc-CTMP and 99m Tc-cyclam in solution was conducted with radio-electrophoresis method simultaneously. The radiochemical purity for both radiolabelled compound was determined by paper chromatography. The purity of radiolabelled 99m Tc-CTMP from cyclam was determined using electrophoresis method. The result show that the amount of cyclam in CTMP can be determined simultaneously using nuclear techniques with the labeling of 99m Tc-CTMP. Electrophoresis method can separated 99m Tc-cyclam, 99m Tc-CTMP, 99m TcO4 and 99m Tc-reduced with limit quantitation of cyclam until 0,4% w/w. (author)

  4. Manganese (III) cyclam complexes with aqua, iodo, nitrito, perchlorato and acetic acid/acetato axial ligands

    DEFF Research Database (Denmark)

    Mossin, Susanne; Sørensen, Henning Osholm; Weihe, Høgni

    2005-01-01

    of the complexes as high-spin d(4) systems. trans-[Mn(cyclam)(OH2)(2)](CF3SO3)(3)center dot H2O is shown to be a convenient starting material for the syntheses of trans cyclam complexes. [Mn(cyclam)(CH3COO)(CH3COOH)](ClO4)(2) exhibits extremely short intermolecular hydrogen bonds resulting in a pseudo-chain...

  5. Synthesis and bacterial metabolism of cis- and trans-2-alkyl analogues of sodium cyclamate.

    Science.gov (United States)

    Wiley, R A; Pearson, D A; Schmidt, V; Wesche, S B; Roxon, J J

    1983-07-01

    Sodium cyclamate is an effective artificial sweetner, which has been banned from the U.SD. market because of alleged carcinogenic properties. It appears that cyclohexylamine, liberated from cyclamate as a result of bacterial mtabolism, is the proximate carcinogen. In an effort to elucidate the extent to which analogues of cyclamate would enter into the bacterial metabolic pathway, as well as any stereochemical requirements which might exist, several 2-alkaly analogues of sodium cyclamate were prepared. It was found that trans-N-(2-methylcyclohexyl)sulfamate (trans-2a) and trans-N-(2-ethylcyclohexyl)sulfamate were hydrolyzed by freshly collected fecal suspensions from rats fed cyclamate, but not from control rats, at the same rate as cyclamate itself. trans-N-(2-Isopropylcyclohexyl)sulfamate (trans-2c) was not hydrolyzed at all. Surprisingly, two of the analogous cis compounds (cis-2a and cis-2c, respectively) were hydrolyzed by fecal suspensions from control, as well as from cyclamate-fed, rats. Moreover, cis-2a was hydrolyzed by incubating it in medium only. Thus, it is apparent that stereochemical influences on the chemical properties of these compounds are substantial. These results do not appear to point the way toward a safe, nonmetabolizable sweetening agent.

  6. Effect of Sodium Cyclamate on the Rat Fetal Exocrine Pancreas: a Karyometric and Stereological Study

    OpenAIRE

    MARTINS, Alex Tadeu; SANTOS, Fabiano de Sant`Ana dos; SCANNAVINO, Fabio Luiz Ferreira; PIRES, Juliana Rico; ZUZA, Elizangela Partata; PADOVANI JUNIOR, Joao Armando; AZOUBEL, Reinaldo; MATEO, Miguel Angel Sala Di; LOPES, Ruberval Armando

    2010-01-01

    The cyclamate, a sweetner substance derived from N-cyclo-hexyl-sulfamic acid, is largely utilized as a non-caloric artificial edulcorant in foods and beverages as well as in the pharmaceutical industry. The objective of this study was to evaluate karyometric and stereological alterations in the rat fetal pancreas resulting from the intraperitoneal administration of sodium cyclamate. The exocrine pancreas of ten fetuses of rats were evaluated, five treated and five controls chosen at random, i...

  7. On-cartridge derivatisation using matrix solid phase dispersion for the determination of cyclamate in foods

    International Nuclear Information System (INIS)

    Li, Jianjun; Liu, Yun; Liu, Qianping; Hui, Junfeng; Liu, Yangzi

    2017-01-01

    A novel method for determination of sodium cyclamate in foods was developed. In this method, a syringe was loaded with the homogeneous mixture of the sample, KMnO 4 powder and silica dispersant and used as a matrix solid phase dispersion (MSPD) reactor. As the reactor was infiltrated with small amounts of concentrated HCl, cyclamate was converted to 2-chlorocyclohexanone quickly and effectively within 5 min and determined by HPLC on a reversed-phase column using UV detection at a wavelength of 310 nm. Comparing with the traditional derivatisation in solution, the better clean-up was provided using on-cartridge derivatisation of MSPD, and much time, labor, and expense were saved. The results showed good linearity (r 2  = 0.9998) over the concentration range of 1–500 mg/L. The limit of detection (LOD) and limits of quantification (LOQ) of the cyclamate were 0.3 mg/L and 1 mg/L respectively. The recoveries ranged from 91.6% to 101.3% with the relative standard deviations (RSDs) in the range of 2.5%–4.3%. - Highlights: • A novel method was developed for the determination of cyclamate in foods. • On cartridge derivatisation, using matrix solid phase dispersion, was developed. • A new derivatisation reaction for cyclamate conversion to 2-chlorocyclohexanone was developed. • The method was rapid, simple, inexpensive, effective.

  8. On-cartridge derivatisation using matrix solid phase dispersion for the determination of cyclamate in foods

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jianjun, E-mail: bootan12@126.com [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, Northwest University, Xi' an 710069 (China); National Engineering Research Center for Miniaturized Detection Systems, Xi' an 710069 (China); Liu, Yun [College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi' an 710062 (China); Liu, Qianping [National Engineering Research Center for Miniaturized Detection Systems, Xi' an 710069 (China); Hui, Junfeng [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, Northwest University, Xi' an 710069 (China); Liu, Yangzi [National Engineering Research Center for Miniaturized Detection Systems, Xi' an 710069 (China)

    2017-06-15

    A novel method for determination of sodium cyclamate in foods was developed. In this method, a syringe was loaded with the homogeneous mixture of the sample, KMnO{sub 4} powder and silica dispersant and used as a matrix solid phase dispersion (MSPD) reactor. As the reactor was infiltrated with small amounts of concentrated HCl, cyclamate was converted to 2-chlorocyclohexanone quickly and effectively within 5 min and determined by HPLC on a reversed-phase column using UV detection at a wavelength of 310 nm. Comparing with the traditional derivatisation in solution, the better clean-up was provided using on-cartridge derivatisation of MSPD, and much time, labor, and expense were saved. The results showed good linearity (r{sup 2} = 0.9998) over the concentration range of 1–500 mg/L. The limit of detection (LOD) and limits of quantification (LOQ) of the cyclamate were 0.3 mg/L and 1 mg/L respectively. The recoveries ranged from 91.6% to 101.3% with the relative standard deviations (RSDs) in the range of 2.5%–4.3%. - Highlights: • A novel method was developed for the determination of cyclamate in foods. • On cartridge derivatisation, using matrix solid phase dispersion, was developed. • A new derivatisation reaction for cyclamate conversion to 2-chlorocyclohexanone was developed. • The method was rapid, simple, inexpensive, effective.

  9. Ciclamato de sódio e rim fetal Sodium cyclamate and fetal kidney

    Directory of Open Access Journals (Sweden)

    José Germano Ferraz de Arruda

    2003-06-01

    Full Text Available O ciclamato é usado como adoçante artificial não calórico em diversos alimentos e bebidas, sendo 30 vezes mais doce que a sacarose sem o sabor amargo da sacarina. Aparece na composição dos produtos como ciclamato de sódio, ciclamato de cálcio e ácido ciclâmico. O ciclamato e a ciclohexilamina, seu principal metabólito, atravessam a barreira placentária em humanos e desse modo podem ser expostos ao feto. O rim de ratos pode ser afetado por elevadas doses de ciclamato de sódio. Estudos sobre efeitos do ciclamato de sódio na espécie humana são necessários, pois, além de poder substituir a sacarose - prejudicial em casos de diabetes ou quando o controle e a redução do peso corporal são essenciais para a saúde dos pacientes - não propicia desenvolvimento de cárie dentária.Cyclamate is used as an artificial non-caloric sweetener in a variety of foods and beverages, being 30 times as sweet as sugar without the bitter after-taste of saccharin. It is present in the formula of products such as sodium and calcium cyclamates and cyclamic acid. Cyclamate and cyclohexylamine, its principal metabolite, can cross the human placenta exposing the fetus. It has been demonstrated in rats that the kidney may be adversely affected by high doses of cyclamate. Studies on the effects of sodium cyclamate in the human species are necessary, because in addition to replacing saccharose - harmful in individuals with diabetes or patients in whom weight reduction and control are essential for health - it does not cause dental caries.

  10. Simultaneous square-wave voltammetric determination of aspartame and cyclamate using a boron-doped diamond electrode.

    Science.gov (United States)

    Medeiros, Roberta Antigo; de Carvalho, Adriana Evaristo; Rocha-Filho, Romeu C; Fatibello-Filho, Orlando

    2008-07-30

    A simple and highly selective electrochemical method was developed for the simultaneous determination of aspartame and cyclamate in dietary products at a boron-doped diamond (BDD) electrode. In square-wave voltammetric (SWV) measurements, the BDD electrode was able to separate the oxidation peak potentials of aspartame and cyclamate present in binary mixtures by about 400 mV. The detection limit for aspartame in the presence of 3.0x10(-4) mol L(-1) cyclamate was 4.7x10(-7) mol L(-1), and the detection limit for cyclamate in the presence of 1.0x10(-4) mol L(-1) aspartame was 4.2x10(-6) mol L(-1). When simultaneously changing the concentration of both aspartame and cyclamate in a 0.5 mol L(-1) sulfuric acid solution, the corresponding detection limits were 3.5x10(-7) and 4.5x10(-6) mol L(-1), respectively. The relative standard deviation (R.S.D.) obtained was 1.3% for the 1.0x10(-4) mol L(-1) aspartame solution (n=5) and 1.1% for the 3.0x10(-3) mol L(-1) cyclamate solution. The proposed method was successfully applied in the determination of aspartame in several dietary products with results similar to those obtained using an HPLC method at 95% confidence level.

  11. αVβ3 Integrin-Targeted Radionuclide Therapy with 64Cu-cyclam-RAFT-c(-RGDfK-)4.

    Science.gov (United States)

    Jin, Zhao-Hui; Furukawa, Takako; Degardin, Mélissa; Sugyo, Aya; Tsuji, Atsushi B; Yamasaki, Tomoteru; Kawamura, Kazunori; Fujibayashi, Yasuhisa; Zhang, Ming-Rong; Boturyn, Didier; Dumy, Pascal; Saga, Tsuneo

    2016-09-01

    The transmembrane cell adhesion receptor αVβ3 integrin (αVβ3) has been identified as an important molecular target for cancer imaging and therapy. We have developed a tetrameric cyclic RGD (Arg-Gly-Asp) peptide-based radiotracer (64)Cu-cyclam-RAFT-c(-RGDfK-)4, which successfully captured αVβ3-positive tumors and angiogenesis by PET. Here, we subsequently evaluated its therapeutic potential and side effects using an established αVβ3-positive tumor mouse model. Mice with subcutaneous U87MG glioblastoma xenografts received single administrations of 37 and 74 MBq of (64)Cu-cyclam-RAFT-c(-RGDfK-)4 (37 MBq/nmol), peptide control, or vehicle solution and underwent tumor growth evaluation. Side effects were assessed in tumor-bearing and tumor-free mice in terms of body weight, routine hematology, and hepatorenal functions. Biodistribution of (64)Cu-cyclam-RAFT-c(-RGDfK-)4 with ascending peptide doses (0.25-10 nmol) and with the therapeutic dose of 2 nmol were determined at 3 hours and at various time points (2 minutes-24 hours) postinjection, respectively, based on which radiation-absorbed doses were estimated. The results revealed that (64)Cu-cyclam-RAFT-c(-RGDfK-)4 dose dependently slowed down the tumor growth. The mean tumor doses were 1.28 and 1.81 Gy from 37 and 74 MBq of (64)Cu-cyclam-RAFT-c(-RGDfK-)4, respectively. Peptide dose study showed that the tumor uptake of (64)Cu-cyclam-RAFT-c(-RGDfK-)4 dose dependently decreased at doses ≥1 nmol, indicating a saturation of αVβ3 with the administered therapeutic doses (1 and 2 nmol). Combined analysis of the data from tumor-bearing and tumor-free mice revealed no significant toxicity caused by 37-74 MBq of (64)Cu-cyclam-RAFT-c(-RGDfK-)4 Our study demonstrates the therapeutic efficacy and safety of (64)Cu-cyclam-RAFT-c(-RGDfK-)4 for αVβ3-targeted radionuclide therapy. (64)Cu-cyclam-RAFT-c(-RGDfK-)4 would be a promising theranostic drug for cancer imaging and therapy. Mol Cancer Ther; 15(9); 2076-85. ©2016 AACR

  12. Rapid analysis of cyclamate in foods and beverages by gas chromatography-electron capture detector (GC-ECD).

    Science.gov (United States)

    Yu, Shengbing; Zhu, Binghui; Lv, Fen; Li, Shaoxiao; Huang, Weixiong

    2012-10-15

    A rapid method for determination of sodium cyclamate in foods and beverages was developed. Sodium cyclamate was converted to N,N-dichloridecyclohexylamine by reaction with sodium hypochlorite under acid condition. N,N-dichloridecyclohexylamine was subsequently extracted by n-hexane and determined by gas chromatography. Conditions such as derivatization time, the concentration of sodium hypochlorite and sulphuric acid were optimised. Amino acids, aliphatic amines, and food additives such as preservatives, dyes and sweeteners showed no interference for quantification of cyclamate. The correlation coefficient of calibration curve was 0.9993 in the range of 5.0-250mg/L. The limits of detection (LOD) and limits of quantification (LOQ) were calculated as three or ten times the signal-to-noise ratio (S/N), respectively. The LOD and LOQ for yellow wine and fruit juice were 0.05 and 0.2mg/L, respectively. The LOD and LOQ for cake and preserved fruit were 0.25 and 0.8mg/kg, respectively. The intra-day and inter-day RSD were 0.28% and 1.1% (n=5), respectively. The method was successfully applied for determination of cyclamate in yellow wine, cake, fruit juice and preserved fruit. This method was simple, fast, and sensitive. It was suitable for the determination of cyclamate in foods and beverages for safety and quality control inspections. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. A cyclam core dendrimer containing dansyl and oligoethylene glycol chains in the branches: protonation and metal coordination.

    Science.gov (United States)

    Branchi, Barbara; Ceroni, Paola; Bergamini, Giacomo; Balzani, Vincenzo; Maestri, Mauro; van Heyst, Jeroen; Lee, Sang-Kyu; Luppertz, Friedhelm; Vögtle, Fritz

    2006-12-04

    We have synthesized a dendrimer (1) consisting of a 1,4,8,11-tetraazacyclotetradecane (cyclam) core, appended with four benzyl substituents that carry, in the 3- and 5-positions, a dansyl amide derivative (of type 2), in which the amide hydrogen is replaced by a benzyl unit that carries an oligoethylene glycol chain in the 3- and 5-positions. All together, the dendrimer contains 16 potentially luminescent moieties (eight dansyl- and eight dimethoxybenzene-type units) and three distinct types of multivalent sites that, in principle, can be protonated or coordinated to metal ions (the cyclam nitrogen atoms, the amine moieties of the eight dansyl units, and the 16 oligoethylene glycol chains). We have studied the absorption and luminescence properties of 1, 2, and 3 in acetonitrile and the changes taking place upon titration with acid and a variety of divalent (Co2+, Ni2+, Cu2+, Zn2+), and trivalent (Nd3+, Eu3+, Gd3+) metal ions as triflate and/or nitrate salts. The results obtained show that: 1) double protonation of the cyclam ring takes place before protonation of the dansyl units; 2) the oligoethylene glycol chains do not interfere with protonation of the cyclam core and the dansyl units in the ground state, but affect the luminescence of the protonated dansyl units; 3) the first equivalent of metal ion is coordinated by the cyclam core; 4) the interaction of the resulting cyclam complex with the appended dansyl units depends on the nature of the metal ion; 5) coordination of metal ions by the dansyl units follows at high metal-ion concentrations; 6) the effect of the metal ion depends on the nature of the counterion. This example demonstrates that dendrimers may exhibit complete functionality resulting from the integration of the specific properties of their component units.

  14. Straightforward grafting approach for cyclam-functionalized screen-printed electrodes for selective Cu(II) determination

    International Nuclear Information System (INIS)

    Jasmin, Jean-Philippe; Ouhenia-Ouadahi, Karima; Miserque, Frédéric; Dumas, Eddy; Cannizzo, Caroline; Chaussé, Annie

    2016-01-01

    We report in this paper an original way to covalently bind the macrocyclic ligand, 1,4,8,11-tetraazacyclotetradecane (cyclam), through diazonium salt chemistry, on the surface of carbon screen-printed electrodes (SPEs). The in situ synthesis of the diazonium salt obtained from the amine precursor derived from the cyclam and its electrografting are described. X-ray Photoelectron Spectroscopy was used to characterize this functionalized surface. Owing to the strong cyclam–Cu(II) affinity, the so called SPE-cyclam can be used as electrochemical sensors for Cu(II) determination at trace levels. The influence of electroanalysis parameters such as the accumulation time and the pH of the medium were investigated. An interference study was carried out with numerous metallic cations and few interference was found for Cu(II) quantification. The described method provided a limit of detection and a limit of quantification of 1.3 × 10"−"8 M and 4.0 × 10"−"8 M, respectively. Interference study and performances show that SPE-cyclam could be considered as efficient sensors for environmental analysis.

  15. Spectrophotometric determination of cyclamate in soft drinks and desserts: complementary collaborative study.

    Science.gov (United States)

    Sjöberg, A M

    1988-01-01

    Fifteen official food control laboratories participated in a collaborative study of a spectrophotometric method to determine cyclamate in a soft drink and a dessert at concentrations of 90-311 mg/L and 202-526 mg/kg, respectively, with blind duplicates and a blank. Average recovery from the soft drink was 97.5%, and from the dessert, 98.6%. Reproducibility relative standard deviations were 4.7-6.5% and 6.9-8.5%, respectively. The outlier percentage was 5.5%. This study complements an earlier work by leading Nordic food laboratories and was designed according to the latest recommendations. The results of this study were compared with those of the earlier collaborative study and with general collaborative results obtained by AOAC.

  16. CYCLAM - Recycling by a Laser-driven Drop Jet from Waste that Feeds AM

    Science.gov (United States)

    Kaplan, Alexander F. H.; Samarjy, Ramiz S. M.

    Additive manufacturing of metal parts is supplied by powder or wire. Manufacturing of this raw material causes additional costs and environmental impact. A new technique is proposed where the feeding directly originates from a metal sheet, which can even be waste. When cutting is done by laser-induced boiling, melt is continuously ejected downwards underneath the sheet. The ejected melt is deposited as a track on a substrate, enabling additive manufacturing by substrate movement along a desired path. The melt first flows downwards as a column and after a few millimeters separates into drops, here about 500 micrometer in diameter, as observed by high speed imaging. The drops incorporate sequentially and calmly into a long melt pool on the substrate. While steel drops formed regular tracks on steel and aluminium substrates, on copper substrate periodic drops solidified instead. For this new technique, called CYCLAM, the laser beam acts indirectly while the drop jet becomes the main tool. From imaging, properties like the width or fluctuations of the drop jet can be statistically evaluated. Despite oscillation of the liquid column, the divergence of the drop jet remained small, improving the precision and robustness. The melt leaves the cut sheet as a liquid column, 1 to 4 mm in length, which periodically separates drops that are transferred as a liquid jet to the substrate. For very short distance of 2 to 3 mm between the two sheets this liquid column can transfer the melt continuously as a liquid bridge. This phenomenon was observed, as a variant of the technique, but the duration of the bridge was limited by fluid mechanic instabilities.

  17. A New Class of Metal-Cyclam-Based Zirconium Metal–Organic Frameworks for CO 2 Adsorption and Chemical Fixation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jie [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry; Usov, Pavel M. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry; Xu, Wenqian [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS) and X-ray Science Division; Celis-Salazar, Paula J. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry; Lin, Shaoyang [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry; Kessinger, Matthew C. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry; Landaverde-Alvarado, Carlos [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemical Engineering and Macromolecules Innovation Inst.; Cai, Meng [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry; May, Ann M. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry; Slebodnick, Carla [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry; Zhu, Dunru [Nanjing Univ. of Technology (China). State Key Lab. of Materials-Oriented Chemical Engineering (MCE) and College of Chemical Engineering; Senanayake, Sanjaya D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Dept. of Chemistry; Morris, Amanda J. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States). Dept. of Chemistry and Macromolecules Innovation Inst.

    2017-12-22

    Metal-organic frameworks (MOFs) have shown great promise in catalysis, mainly due to their high content of active centers, large internal surface areas, tunable pore size, and versatile chemical functionalities. However, it is a challenge to rationally design and construct MOFs that can serve as highly stable and reusable heterogeneous catalysts. Here two new robust 3D porous metal-cyclam-based zirconium MOFs, denoted VPI-100 (Cu) and VPI-100 (Ni), have been prepared by a modulated synthetic strategy. The frameworks are assembled by eight-connected Zr-6 clusters and metallocyclams as organic linkers. Importantly, the cyclam core has accessible axial coordination sites for guest interactions and maintains the electronic properties exhibited by the parent cyclam ring. The VPI-100 MOFs exhibit excellent chemical stability in various organic and aqueous solvents over a wide pH range and show high CO2 uptake capacity (up to similar to 9.83 wt% adsorption at 273 K under 1 atm). Moreover, VPI-100 MOFs demonstrate some of the highest reported catalytic activity values (turnover frequency and conversion efficiency) among Zr-based MOFs for the chemical fixation of CO2 with epoxides, including sterically hindered epoxides. The MOFs, which bear dual catalytic sites (Zr and Cu/Ni), enable chemistry not possible with the cyclam ligand under the same conditions and can be used as recoverable stable heterogeneous catalysts without losing performance.

  18. Cyclam Derivatives with a Bis(phosphinate) or a Phosphinato-Phosphonate Pendant Arm: Ligands for Fast and Efficient Copper(II) Complexation for Nuclear Medical Applications

    Czech Academy of Sciences Publication Activity Database

    David, T.; Kubíček, V.; Gutten, Ondrej; Lubal, P.; Kotek, J.; Pietzsch, H.-J.; Rulíšek, Lubomír; Hermann, P.

    2015-01-01

    Roč. 54, č. 24 (2015), s. 11751-11766 ISSN 0020-1669 R&D Projects: GA ČR(CZ) GA14-31419S Grant - others:COST(XE) TD1004 Institutional support: RVO:61388963 Keywords : cyclam derivatives * radiolabelling * quantum chemical calculations * copper(II) chelation Subject RIV: CA - Inorganic Chemistry Impact factor: 4.820, year: 2015

  19. Homo- and heterodinuclear coordination polymers based on a tritopic cyclam bis-terpyridine unit: Structure and rheological properties

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Li; Fan, Jiangxia; Ren, Yong; Xiong, Kun [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); Yan, Minhao, E-mail: yanminhao@swust.edu.cn [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); Tuo, Xianguo, E-mail: tuoxg@swust.edu.cn [Laboratory of National Defense for Radioactive Waste and Environmental Security, Southwest University of Science and Technology, Mianyang 621010 (China); Terech, Pierre [SPrAM, UMR CEA/CNRS/UJF-Grenoble 1, INAC, Grenoble F-38054 (France); Royal, Guy [Université Joseph Fourier Grenoble I, Département de Chimie Moléculaire, UMR CNRS-5250, Institut de Chimie Moléculaire de Grenoble, FR CNRS-2607, BP 53, 38041 Grenoble Cedex 9 (France)

    2015-03-01

    An innovative coordination polymer based on a tritopic ligand having the bis-terpyridine cyclam (CHTT) unit is explored. Homo- or heteronuclear 1D coordination polymers can be formed with bivalent metal ions such as Co(II) and Ni(II) in solvent DMF. Creep-recovery curves of the (Co{sup II}){sub 2}CHTT gels formed from 1D coordination polymers were analyzed with the Burgers model and demonstrated an original self-healing property, unusual in the class of molecular gels. The influence of the metal type was studied through the structural features using small-angle neutron scattering (SANS) experiments. In gels, the corresponding network involves genuine fibers (R ≈ 35 Å), bundles of these fibers and also a fraction of finite size aggregates (rods with aspect ratio f ≈ 3–5). We found that the distribution of these latter structural components is sensitive to the metal ions type. Such tritopic 1D coordination polymers exhibit a range of original structural features and a facile control of the developed structures in solutions and gels by tuning their thermodynamic parameters. The versatility associated to the intrinsic dynamic ability of the systems should pave the way to original properties for molecular devices. - Graphical abstract: A tritopic ligand with a bis-terpyridine cyclam (CHTT) unit can form homo- and heterobinuclear coordination polymers with bivalent metal ions in DMF. Gels exhibit a remarkable self-healing property while structures of solutions and gels are studied by small-angle neutron scattering. - Highlights: • Homo- and heteronuclear coordination polymers based on innovative tritopic ligand. • The gels formed from the coordination polymers demonstrated self-healing property. • Influence of the metal type was studied through the structural properties by SANS. • Versatility of the singular system present original properties for molecular device.

  20. Synthesis and characterization of monomeric and polymeric Cu(II) complexes of 3,4-ethylenedioxythiophene-functionalized with cyclam ligand

    International Nuclear Information System (INIS)

    Velauthamurty, Kuhamoorthy; Higgins, Simon J.; Rajapakse, R.M. Gamini; Bandara, H.M.N.; Shimomura, Masaru

    2010-01-01

    A functionalized EDOT derivative with 1,4,8,11-tetraazacyclotetradecane (cyclam) ligand pendant to the ethylene bridge (4) and its complexes [M(4)(BF 4 ) 2 ], where M(II) = Cu(II), was prepared and characterized. Their electrochemical copolymerization with EDOT was studied. The electro-co-polymerized films were characterized by electrochemical methods, X-ray photoelectron spectroscopy and by X-ray fluorescence spectroscopy. The co-polymerization method was found to afford a good control of the metal concentration in the polymer matrix and represents a good technique for preparing electronically conductive polymers containing redox-active metal complexes.

  1. Chemical and photochemical properties of a ruthenium nitrosyl complex with the N-monosubstituted cyclam 1-(3-Propylammonium)-1,4,8,11-tetraazacyclotetradecane

    International Nuclear Information System (INIS)

    Ferreira, Kleber Q.; Tfouni, Elia

    2010-01-01

    The amine-functionalized trans-[Ru(NO)Cl(1-pramcyH)](PF 6 ) 3 complex (1-pramcyH = 1-(3-propylammonium)-1,4,8,11-tetraazacyclotetradecane) was synthesized from trans-[Ru Cl(tfms) (1-pramcyH)](tfms) 2 (tfms trifluoromethanesulfonate) in acidic aqueous solution in the presence of nitric oxide (NO). The complex was characterized by elemental, spectroscopic (UV-Vis, IR, 1 H and 13 C NMR) and electrochemical analyses. Two pKa values (7.0 and 8.2) were estimated for trans-[Ru(NO)Cl(1-pramcyH)](PF 6 ) 3 and were assigned to one of the cyclam nitrogen protons and to the protonated aminopropyl group. Reduction of trans-[Ru(NO)Cl(1-pramcyH)] 3+ results in rapid loss of chloride followed by slower loss of NO, while irradiation of the complex in aqueous deaerated conditions suggests photochemical labilization of NO. The quantum yields for NO photoaquation decrease as the irradiation wavelength increases, being noticeable only at λ irr 3+ , which contains an aminopropyl substituted cyclam, parallels that reported for the analogous complex with the unsubstituted ligand, but differs from that described for the complex in which carboxypropyl is the substituent. (author)

  2. Chemical and photochemical properties of a ruthenium nitrosyl complex with the N-monosubstituted cyclam 1-(3-Propylammonium)-1,4,8,11-tetraazacyclotetradecane

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Kleber Q.; Tfouni, Elia, E-mail: eltfouni@usp.b [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Quimica

    2010-07-01

    The amine-functionalized trans-[Ru(NO)Cl(1-pramcyH)](PF{sub 6}){sub 3} complex (1-pramcyH = 1-(3-propylammonium)-1,4,8,11-tetraazacyclotetradecane) was synthesized from trans-[Ru Cl(tfms) (1-pramcyH)](tfms){sub 2} (tfms trifluoromethanesulfonate) in acidic aqueous solution in the presence of nitric oxide (NO). The complex was characterized by elemental, spectroscopic (UV-Vis, IR, {sup 1}H and {sup 13}C NMR) and electrochemical analyses. Two pKa values (7.0 and 8.2) were estimated for trans-[Ru(NO)Cl(1-pramcyH)](PF{sub 6}){sub 3} and were assigned to one of the cyclam nitrogen protons and to the protonated aminopropyl group. Reduction of trans-[Ru(NO)Cl(1-pramcyH)]{sup 3+} results in rapid loss of chloride followed by slower loss of NO, while irradiation of the complex in aqueous deaerated conditions suggests photochemical labilization of NO. The quantum yields for NO photoaquation decrease as the irradiation wavelength increases, being noticeable only at lambda{sub irr} < 370 nm, and increase as pH increases. The behavior of trans-[Ru(NO)Cl(1-pramcyH)]{sup 3+}, which contains an aminopropyl substituted cyclam, parallels that reported for the analogous complex with the unsubstituted ligand, but differs from that described for the complex in which carboxypropyl is the substituent. (author)

  3. PET imaging and biodistribution analysis of the effects of succinylated gelatin combined with L-lysine on renal uptake and retention of ⁶⁴Cu-cyclam-RAFT-c(-RGDfK-)₄ in vivo.

    Science.gov (United States)

    Jin, Zhao-Hui; Furukawa, Takako; Sogawa, Chizuru; Claron, Michael; Aung, Winn; Tsuji, Atsushi B; Wakizaka, Hidekatsu; Zhang, Ming-Rong; Boturyn, Didier; Dumy, Pascal; Fujibayashi, Yasuhisa; Saga, Tsuneo

    2014-04-01

    (64)Cu-cyclam-RAFT-c(-RGDfK-)4, an αVβ3 integrin-targeting tetrameric cyclic RGD peptide probe, is a potential theranostic compound for positron emission tomography (PET) of tumor angiogenesis and for internal radiotherapy owing to the multiple decay modes of (64)Cu. Since kidneys are dose-limiting organs in internal radiotherapy, we aimed to reduce the renal accumulation of (64)Cu-cyclam-RAFT-c(-RGDfK-)4 by co-injection with Gelofusine (GF), a succinylated gelatin solution, and/or L-lysine (Lys), and to explore, for the first time, the related mechanisms using the noninvasive and quantitative PET imaging technology. Biodistribution assays, dynamic and static PET scans, and metabolism studies with radio-thin-layer chromatography (radio-TLC) were performed in healthy or αVβ3-positive tumor-bearing mice. In the results, co-injection with GF markedly reduced the renal uptake and slightly increased the tumor uptake of (64)Cu-cyclam-RAFT-c(-RGDfK-)4. L-Lysine alone had no effect on the probe biodistribution, but the combined use of Lys and GF tended to enhance the effect of GF. Dynamic PET and metabolite analysis by radio-TLC highly revealed that GF blocks the renal reabsorption of (64)Cu-cyclam-RAFT-c(-RGDfK-)4, but does not interfere with its metabolism and excretion. In conclusion, administration of GF and Lys is a useful strategy for kidney protection in (64)Cu-cyclam-RAFT-c(-RGDfK-)4-based internal radiotherapy. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  4. Noninvasive visualization and quantification of tumor {alpha}{sub V{beta}3} integrin expression using a novel positron emission tomography probe, {sup 64}Cu-cyclam-RAFT-c(-RGDfK-){sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Zhao-Hui [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Furukawa, Takako, E-mail: tfuru@nirs.go.j [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Biomedical Imaging Research Center, University of Fukui, Fukui 910-1193 (Japan); Galibert, Mathieu; Boturyn, Didier [Departement de Chimie Moleculaire, UMR 5250, CNRS-Universite Joseph Fourier, 38041 Grenoble Cedex 9 (France); Coll, Jean-Luc [INSERM U823, Institut Albert Bonniot and Universite Joseph Fourier, 38706 La Tronche Cedex, Grenoble (France); Fukumura, Toshimitsu; Saga, Tsuneo [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Dumy, Pascal [Departement de Chimie Moleculaire, UMR 5250, CNRS-Universite Joseph Fourier, 38041 Grenoble Cedex 9 (France); Fujibayashi, Yasuhisa [Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Biomedical Imaging Research Center, University of Fukui, Fukui 910-1193 (Japan)

    2011-05-15

    Introduction: The {alpha}{sub V{beta}3} integrin is a well-known transmembrane receptor involved in tumor invasion, angiogenesis and metastasis. Our aim was to evaluate a novel positron emission tomography (PET) probe, {sup 64}Cu-cyclam-RAFT-c(-RGDfK-){sub 4}, for noninvasive visualization and quantification of {alpha}{sub V{beta}3} integrin expression. Methods: RAFT-c(-RGDfK-){sub 4}, a tetrameric cyclic Arg-Gly-Asp (RGD)-based peptide, was conjugated with a bifunctional chelator, 1,4,8,11-tetraazacyclotetradecane (cyclam), radiolabeled with the positron emitter {sup 64}Cu and evaluated in vitro by cell binding and competitive inhibition assays and in vivo by biodistribution and receptor blocking studies, and PET imaging. The following cell lines, human embryonic kidney HEK293({beta}{sub 1}) [{alpha}{sub V{beta}3}-negative] and HEK293({beta}{sub 3}) [{alpha}{sub V{beta}3}-overexpressing] and human glioblastoma U87MG [naturally expressing {alpha}{sub V{beta}3}], together with their subcutaneous xenografts in athymic nude mice, were used for the present study. The expression levels of {alpha}{sub V{beta}3} on these cell lines and tumor xenografts were analyzed by flow cytometry and sodium dodecyl sulfate-polyacrylamide gel electrophoresis/autoradiography, respectively. Results: {sup 64}Cu-cyclam-RAFT-c(-RGDfK-){sub 4} demonstrated the in vitro and in vivo specificity for the {alpha}{sub V{beta}3} integrin and displayed rapid blood clearance, predominantly renal excretion and low uptake in nontumor tissues. Tumor uptake of {sup 64}Cu-cyclam-RAFT-c(-RGDfK-){sub 4} (3 h postinjection) in HEK293({beta}{sub 3}) (high levels of {alpha}{sub V{beta}3}), U87MG (moderate levels of {alpha}{sub V{beta}3}) and HEK293({beta}{sub 1}) (undetectable levels of {alpha}{sub V{beta}3}) tumors was 9.35%{+-}1.19%, 3.46%{+-}0.45% and 1.18%{+-}0.30% injected dose per gram, respectively, with a strong and positive correlation with the tumor {alpha}{sub V{beta}3} expression levels

  5. Sub-minute method for simultaneous determination of aspartame, cyclamate, acesulfame-K and saccharin in food and pharmaceutical samples by capillary zone electrophoresis.

    Science.gov (United States)

    Vistuba, Jacqueline Pereira; Dolzan, Maressa Danielli; Vitali, Luciano; de Oliveira, Marcone Augusto Leal; Micke, Gustavo Amadeu

    2015-05-29

    This paper reports the development of a sub-minute separation method by capillary zone electrophoresis for the determination of aspartame, cyclamate, acesulfame-K and saccharin in food products and pharmaceutical samples. Separations were performed in a fused uncoated silica capillary with UV detection at 220nm. Samples and standards were injected hydrodynamically using the short-end injection procedure. The electrophoretic system was operated under constant voltage of -30kV. The background electrolyte was composed of 45mmolL(-1) 2-amino-2-(hydroxymethyl)-1,3-propanediol and 15mmolL(-1) benzoic acid at pH 8.4. The separation time for all analytes was less than 1min. Evaluation of analytical parameters of the method showed good linearity (r(2)>0.9972), limit of detection of 3.3-6.4mgL(-1), intermediate precision better than 9.75% (peak area of sample) and recovery in the range of 91-117%. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Radiolabeling of HTE1PA: A new monopicolinate cyclam derivative for Cu-64 phenotypic imaging. In vitro and in vivo stability studies in mice

    International Nuclear Information System (INIS)

    Frindel, Mathieu; Camus, Nathalie; Rauscher, Aurore; Bourgeois, Mickaël; Alliot, Cyrille; Barré, Louisa; Gestin, Jean-François; Tripier, Raphaël; Faivre-Chauvet, Alain

    2014-01-01

    Introduction: HTE1PA, a monopicolinate-N-alkylated cyclam-based ligand has previously demonstrated fast complexation process, high kinetic inertness and important thermodynamic and electrochemical stability with respect to natural copper. In this work we first developed a new synthetic route to obtain HTE1PA in good yields. Then, we investigated HTE1PA chelation properties towards copper-64 and assessed in vitro and in vivo stability of the resulting compound. Methods: Radiolabeling of HTE1PA with copper-64 was tested at different ligand concentrations in ammonium acetate medium. In vitro stability study was carried out by incubating [ 64 Cu]TE1PA complex in human serum at both 37 °C and 4 °C; chromatographic controls were performed over 24 h. Biodistribution, pharmacokinetic and hepatic metabolism of [ 64 Cu]TE1PA were conducted in BALC/c mice in comparison with [ 64 Cu]acetate and [ 64 Cu]DOTA, used as a reference ligand. Results: The promising results obtained for natural copper complexation were confirmed. HTE1PA was quantitatively radiolabeled in 15 min at room temperature. The resulting complex showed high serum stability. [ 64 Cu]TE1PA induced a significant uptake in the liver and kidneys at early biodistribution time point. Nevertheless, a high speed wash out was observed at 24 h leading to significantly lower uptake into the liver compared to [ 64 Cu]DOTA. The metabolism study was consistent with a high resistance to transchelation as the initial uptake into liver matches with the intact form of [ 64 Cu]TE1PA. Conclusion: Despite the partial elimination of HTE1PA – as copper-64 complex – through the hepatic route, its high selectivity for copper and its resistance to transchelation make it a promising ligand for antibody radiolabeling with either copper-64 or copper-67

  7. Micro-positron emission tomography/contrast-enhanced computed tomography imaging of orthotopic pancreatic tumor-bearing mice using the αvβ₃ integrin tracer ⁶⁴Cu-labeled cyclam-RAFT-c(-RGDfK-)₄.

    Science.gov (United States)

    Aung, Winn; Jin, Zhao-Hui; Furukawa, Takako; Claron, Michael; Boturyn, Didier; Sogawa, Chizuru; Tsuji, Atsushi B; Wakizaka, Hidekatsu; Fukumura, Toshimitsu; Fujibayashi, Yasuhisa; Dumy, Pascal; Saga, Tsuneo

    2013-09-01

    The purpose of this study was to develop a clinically relevant orthotopic xenotransplantation model of pancreatic cancer and to perform a preclinical evaluation of a new positron emission tomography (PET) imaging probe, ⁶⁴Cu-labeled cyclam-RAFT-c(-RGDfK-)₄ peptide (⁶⁴Cu-RAFT-RGD), using this model. Varying degrees of αvβ₃ integrin expression in several human pancreatic cancer cell lines were examined by flow cytometry and Western blotting. The cell line BxPC-3, which is stably transfected with a red fluorescence protein (RFP), was used for surgical orthotopic implantation. Orthotopic xenograft was established in the pancreas of recipient nude mice. An in vivo probe biodistribution and receptor blocking study, preclinical PET imaging coregistered with contrast-enhanced computed tomography (CECT) comparing ⁶⁴Cu-RAFT-RGD and ¹⁸F-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) accumulation in tumor, postimaging autoradiography, and histologic and immunohistochemical examinations were done. Biodistribution evaluation with a blocking study confirmed that efficient binding of probe to tumor is highly αvβ₃ integrin specific. ⁶⁴Cu-RAFT-RGD PET combined with CECT provided for precise and easy detection of cancer lesions. Autoradiography, histologic, and immunohistochemical examinations confirmed the accumulation of ⁶⁴Cu-RAFT-RGD in tumor versus nontumor tissues. In comparative PET studies, ⁶⁴Cu-RAFT-RGD accumulation provided better tumor contrast to background than ¹⁸F-FDG. Our results suggest that ⁶⁴Cu-RAFT-RGD PET imaging is potentially applicable for the diagnosis of αvβ₃ integrin-expressing pancreatic tumors.

  8. Micro–Positron Emission Tomography/Contrast-Enhanced Computed Tomography Imaging of Orthotopic Pancreatic Tumor–Bearing Mice Using the αvβ3 Integrin Tracer 64Cu-Labeled Cyclam-RAFT-c(-RGDfK-4

    Directory of Open Access Journals (Sweden)

    Winn Aung

    2013-09-01

    Full Text Available The purpose of this study was to develop a clinically relevant orthotopic xenotransplantation model of pancreatic cancer and to perform a preclinical evaluation of a new positron emission tomography (PET imaging probe, 64Cu-labeled cyclam-RAFT-c(-RGDfK-4 peptide (64Cu-RAFT-RGD, using this model. Varying degrees of αvβ3 integrin expression in several human pancreatic cancer cell lines were examined by flow cytometry and Western blotting. The cell line BxPC-3, which is stably transfected with a red fluorescence protein (RFP, was used for surgical orthotopic implantation. Orthotopic xenograft was established in the pancreas of recipient nude mice. An in vivo probe biodistribution and receptor blocking study, preclinical PET imaging coregistered with contrast-enhanced computed tomography (CECT comparing 64Cu-RAFT-RGD and 18F-fluoro-2-deoxy-D-glucose (18F-FDG accumulation in tumor, postimaging autoradiography, and histologic and immunohistochemical examinations were done. Biodistribution evaluation with a blocking study confirmed that efficient binding of probe to tumor is highly αvβ3 integrin specific. 64Cu-RAFT-RGD PET combined with CECT provided for precise and easy detection of cancer lesions. Autoradiography, histologic, and immunohistochemical examinations confirmed the accumulation of 64Cu-RAFT-RGD in tumor versus nontumor tissues. In comparative PET studies, 64Cu-RAFT-RGD accumulation provided better tumor contrast to background than 18F-FDG. Our results suggest that 64Cu-RAFT-RGD PET imaging is potentially applicable for the diagnosis of αvβ3 integrin–expressing pancreatic tumors.

  9. Synthesis and structural characterization of two new layered inorganic-organic hybrid zinc phosphites templated by cyclam: Zn(HPO.sub.3./sub.).sub.2./sub. . 0.5(C.sub.10./sub.H.sub.28./sub.N.sub.4./sub.) and Zn.sub.2./sub.(HPO.sub.3./sub.).sub.3./sub. . 0.5(C.sub.10./sub.H.sub.28./sub.N.sub.4./sub.)

    Czech Academy of Sciences Publication Activity Database

    Halime, I.; Bezgour, A.; Fahim, M.; Dušek, Michal; Fejfarová, Karla; Lachkar, M.; El Bali, B.

    2011-01-01

    Roč. 41, č. 2 (2011), s. 223-229 ISSN 1074-1542 Grant - others:AV ČR(CZ) AP0701 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : hybrid phosphates * cyclam * wet chemistry * single crystal structure * IR spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.566, year: 2011

  10. Oxidation of hydrogen peroxide by [Ni (cyclam)] in aqueous acidic ...

    Indian Academy of Sciences (India)

    Oxidation of hydrogen peroxide by tris(2,2 -bipyridine) and tris(4,4 -dimethyl-2,2 - bipyridine) complexes of osmium(III), iron(III), ruthenium(III), and nickel(III) studied in acidic and neutral aqueous media, show an inverse acid depen- dence over the pH the range 6.0–8.5.12 Kinetic mea- surements with an excess of H2O2 ...

  11. Bifunctional cyclam-based ligands with phosphorus acid pendant moieties for radiocopper separation: thermodynamic and kinetic studies

    Czech Academy of Sciences Publication Activity Database

    Paúrová, M.; Havlíčková, J.; Pospíšilová, Aneta; Vetrík, Miroslav; Císařová, I.; Stephan, H.; Pietzsch, H.-J.; Hrubý, Martin; Hermann, P.; Kotek, J.

    2015-01-01

    Roč. 21, č. 12 (2015), s. 4671-4687 ISSN 0947-6539 R&D Projects: GA ČR GAP304/12/0950 Institutional support: RVO:61389013 Keywords : copper * ion-selective resins * kinetics Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 5.771, year: 2015

  12. Paramagnetic F-19 Relaxation Enhancement in Nickel(II) Complexes of N-Trifluoroethyl Cyclam Derivatives and Cell Labeling for F-19 MRI

    Czech Academy of Sciences Publication Activity Database

    Blahut, J.; Bernášek, K.; Gálisová, A.; Herynek, V.; Císařová, I.; Kotek, J.; Lang, J.; Matějková, Stanislava; Hermann, P.

    2017-01-01

    Roč. 56, č. 21 (2017), s. 13337-13348 ISSN 0020-1669 Institutional support: RVO:61388963 Keywords : magnetic resonance * clinical applications * macrocyclic ligands Subject RIV: CA - Inorganic Chemistry OBOR OECD: Inorganic and nuclear chemistry Impact factor: 4.857, year: 2016

  13. Zn(II)-cyclam based chromogenic sensors for recognition of ATP in aqueous solution under physiological conditions and their application as viable staining agents for microorganism.

    Science.gov (United States)

    Mahato, Prasenjit; Ghosh, Amrita; Mishra, Sanjiv K; Shrivastav, Anupama; Mishra, Sandhya; Das, Amitava

    2011-05-02

    Two chromogenic complexes, L.Zn (where L is (E)-4-((4-(1,4,8,11-tetraazacyclotetradecan-1-ylsulfonyl)phenyl)diazenyl)-N,N-dimethylaniline) and its [2]pseudorotaxane form (α-CD.L.Zn), were found to bind preferentially to adenosine triphosphate (ATP), among all other common anions and biologically important phosphate (AMP, ADP, pyrophosphate, and phosphate) ions in aqueous HEPES buffer medium of pH 7.2. Studies with live cell cultures of prokaryotic microbes revealed that binding of these two reagents to intercellular ATP, produced in situ, could be used in delineating the gram-positive and the gram-negative bacteria. More importantly, these dyes were found to be nontoxic to living microbes (eukaryotes and prokaryotes) and could be used for studying the cell growth dynamics. Binding to these two viable staining agents to intercellular ATP was also confirmed by spectroscopic studies on cell growth in the presence of different respiratory inhibitors that influence the intercellular ATP generation. © 2011 American Chemical Society

  14. Estimated intake of intense sweeteners from non-alcoholic beverages in Denmark, 2005

    DEFF Research Database (Denmark)

    Leth, Torben; Jensen, U.; Fagt, Sisse

    2008-01-01

    In 2005, 76 out of 177 analysed samples of non-alcoholic beverages were found to contain the intense sweeteners cyclamate, acesulfame-K, aspartame, and saccharin. The content of cyclamate did not exceed the now permitted maximum level in the European Union of 250 mg l(-1) in soft drinks. The esti......In 2005, 76 out of 177 analysed samples of non-alcoholic beverages were found to contain the intense sweeteners cyclamate, acesulfame-K, aspartame, and saccharin. The content of cyclamate did not exceed the now permitted maximum level in the European Union of 250 mg l(-1) in soft drinks...

  15. PENETAPAN KADAR SIKLAMAT DALAM SIRUP MERAH YANG DIJUAL DI BANJARMASIN UTARA

    Directory of Open Access Journals (Sweden)

    Siska Musiam

    2016-03-01

    Full Text Available Food additives are ingredients that added to food to affect the nature or form of food. One of the food additives is sweetener. Synthetic sweetener that commonly used in food and beverage industry is cyclamate. Cyclamate excessive consumption will cause tumors and cancer. The Codex Alimentarius Commission (CAC established that the maximum levels of cyclamate that could be consumed by the body is 500 – 3000 mg/kg body weight. Therefore, this study aims to determine levels of cyclamate in red syrup that sold in Banjarmasin Utara. Identification of cyclamate used precipitation method with HCl 10%, BaCl2 10% and NaNO2 10% as reagents, and determination of cyclamate levels performed by gravimetric method. The results showed that 6 samples from 15 samples of red syrup which sold in Banjarmasin Utara contained cyclamate sweetener. Cyclamate contents were found in positive samples examined by gravimetric method and the results respectively were 46,21 mg/kg; 71,26 mg/kg; 97,86 mg/kg; 74,82 mg/kg; 84,46 mg/kg; and 105,24 mg/kg body weight. The results did not exceess the threshold if compare to the maximum levels that set by CAC, that were 500 – 3000 mg/kg body weight.

  16. Estimated intake of intense sweeteners from non-alcoholic beverages in Denmark

    DEFF Research Database (Denmark)

    Leth, Torben; Fabricius, N.; Fagt, Sisse

    2007-01-01

    In 1999, 116 samples of non-alcoholic beverages were analysed for the intense sweeteners cyclamate, acesulfame-K, aspartame and saccharin. High contents of cyclamate close to the maximum permitted level in 1999 of 400 mgl(-1) were found in many soft drinks. The estimated intake of the sweeteners...

  17. Incorporation of μ3-CO3 into an MnIII/MnIV Mn12 cluster: {[(cyclam)MnIV(μ-O)2MnIII(H2O)(μ-OH)]6(μ3-CO3)2}Cl8·24H2O

    Science.gov (United States)

    Levaton, Ben B.; Olmstead, Marilyn M.

    2010-01-01

    The centrosymmetric title cluster, hexa­aquadi-μ3-carbonato-hexa­cyclamhexa-μ2-hydroxido-dodeca-μ2-oxido-hexa­mang­an­ese(IV)hexa­manganese(III) octa­chloride tetra­cosa­hydrate, [Mn12(CO3)2O12(OH)6(C10H24N4)6(H2O)6]Cl8·24H2O, has two μ3-CO3 groups that not only bridge octahedrally coordinated MnIII ions but also act as acceptors to two different kinds of hydrogen bonds. The carbonate anion is planar within experimental error and has an average C—O distance of 1.294 (4) Å. The crystal packing is stabilized by O—H⋯Cl, O—H⋯O, N—H⋯Cl and N—H⋯O hydrogen bonds. Two of the four independent chloride ions are disordered over five positions, and eight of the 12 independent water mol­ecules are disordered over 21 positions. PMID:21587382

  18. Kinetics and mechanisms of the reactions of alkyl radicals with oxygen and with complexes of Co(III), Ru(III), and Ni(III)

    International Nuclear Information System (INIS)

    Kelley, D.

    1990-01-01

    The kinetics of the reactions of C 2 H 5 radical with Co(NH 3 ) 5 X 2+ , Ru(NH 3 ) 5 X 2+ , and Co(dmgH) 2 (X) (Y) (X = Br, Cl, N 3 , SCN; Y = H 2 O, CH 3 CN) complexes were studied using laser flash photolysis of ethylcobalt complexes. The kinetics were obtained by the kinetic probe method. Some relative rate constants were also determined by a competition method based on ethyl halide product ratios. The kinetics of colligation reactions of a series of alkyl radicals with β-Ni(cyclam) 2+ were studied using flaser flash photolysis of alkylcobalt complexes. Again, the kinetics were obtained by employing the kinetic probe competition method. The kinetics of the unimolecular homolysis of a series of RNi(cyclam)H 2 O 2+ were studied. Activation parameters were obtained for the unimolecular homolysis of C 2 H 5 Ni(cyclam)H 2 O 2+ . Kinetic and thermodynamic data obtained from these reactions were compared with those for the σ-bonded organometallic complexes. The kinetics of the unimolecular homolysis of a series of RNi(cyclam)H 2 O 2+ complexes were studied by monitoring the formation of the oxygen insertion product RO 2 Ni(cyclam)H 2 O 2+ . The higher rate constants for the reactions of alkyl radicals with oxygen in solution, as compared with those measured in the gas phase, were discussed. 30 refs

  19. Low-calorie sweeteners in food and food supplements on the Italian market.

    Science.gov (United States)

    Janvier, Steven; Goscinny, Séverine; Le Donne, Cinzia; Van Loco, Joris

    2015-01-01

    This study determines the occurrence and concentration levels of artificial low-calorie sweeteners (LCSs) in food and food supplements on the Italian market. The analysed sample set (290 samples) was representative of the Italian market and comprised of beverages, jams, ketchups, confectionery, dairy products, table-top sweeteners and food supplements. All samples were analysed via UPLC-MS/MS. The method was in-house validated for the analysis of seven LCSs (aspartame, acesulfame-K, saccharin, sucralose, cyclamate, neotame and neohesperidin dihydrochalcone) in food and for five LCSs (aspartame, acesulfame-K, saccharin, cyclamate and sucralose) in food supplements. Except for cyclamate in one beverage which exceeded the maximum level (ML) with 13%, all concentrations measured in food were around or below the ML. In food supplements, 40 of the 52 samples (77%) were found to be above the ML, with exceedances of up to 200% of the ML.

  20. The effect of sweeteners and milk type on the rheological properties ...

    African Journals Online (AJOL)

    The aim of the study was, to determine effects of sweeteners and milk type on the rheological and sensorial properties of reduced calorie salep drink. In addition to sugar, three different sweeteners; aspartame, saccharine and cyclamate as well as three different milk types; full-fat, low-fat and non-fat; were used for sample ...

  1. Hamid et al (21)

    African Journals Online (AJOL)

    DELL

    sweeteners. It is a forest under-storey herb in the. Marantaceae native to equatorial Africa, where its leaves are locally used to wrap food and as material for roofing and woven ... The banning of the artificial sweetener, sodium cyclamate in the USA in ... properties of non-volatile extracts of T. denielli leaves. MATERIALS ...

  2. Intrinsic viscosity of guar gum in sweeteners solutions | Samavati ...

    African Journals Online (AJOL)

    Rheological methods were applied to study the effect of sweeteners on the rheological behavior of guar gum in dilute solutions. The concentration of the sweeteners were 0.1, 0.2%w/v for aspartame, acesulfame-k and cyclamate, and 0.001, 0.002%w/v for neotame. Gum was evaluated for intrinsic viscosity by various ...

  3. Antiferromagnetic coupling in a six-coordinate high spin cobalt(II)-semiquinonato complex.

    Science.gov (United States)

    Caneschi, Andrea; Dei, Andrea; Gatteschi, Dante; Tangoulis, Vassilis

    2002-07-01

    The 3,5-di-tert-butyl-catecholato and 9,10-phenanthrenecatecholato adducts of the cobalt-tetraazamacrocycle complex Co(Me(4)cyclam)(2+) (Me(4)cyclam = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane) were synthesized and oxidized. The oxidation reaction products were isolated in the solid state as hexafluorophosphate derivatives. Both these complexes can be formulated as 1:1 cobalt(II)-semiquinonato complexes, that is, Co(Me(4)cyclam)(DBSQ)PF(6) (1) and Co(Me(4)cyclam)(PhSQ)PF(6) (2), in the temperature range 4-300 K, in striking contrast with the charge distribution found in similar adducts formed by related tetraazamacrocycles. The synthesis strategy and the structural, spectroscopic, and magnetic properties are reported and discussed. The crystallographic data for 2 are as follows: monoclinic, space group P2(1)/a, nomicron. 14, a = 14.087(4) A, b = 15.873(4) A, c = 14.263 (7) A, alpha = 89.91(3) degrees, beta = 107.34(2) degrees, gamma = 90.08(2) degrees, Z = 4. Both these complexes are characterized by triplet electronic ground states arising from the antiferromagnetic coupling between the high-spin d(7) metal ion and the radical ligand.

  4. Artificial Sweeteners as Food Additives (Turkish with English Abstract

    Directory of Open Access Journals (Sweden)

    2015-02-01

    Full Text Available In this review some artificial sweeteners (saccharin, cyclamate and aspartame as food additives are looked over for their usage purposes and the effects on health. The problems of public health caused by some artificial sweeteners are assessed according the recent scientific publication on the subject.

  5. Synthesis of several tetraaza macrocyclic amine ligands and the biodistribution of their Tc-complexes

    International Nuclear Information System (INIS)

    Ketring, A.R.

    1982-01-01

    Several macrocyclic tetraaza ligands were synthesized and their /sup 99m/Tc-complexes prepared. The biological distribution of these complexes was examined to determine their possible utility as radiodiagnostic agents. The simplest of the macrocyclic tetraaza ligands studied, cyclam, forms a very stable cationic complex with Tc when pertechnetate is reduced with stannous ion in an aqueous solution of the ligand. When injected intravenously into mice Tc-cyclam was excreted predominantly by the urinary system. Derivatives of cyclam which were synthesized contained aromatic or aliphatic substituents and formed more lipophilic complexes with Tc. The complexes were formed in high yield as determined by paper chromatography, thin layer chromatography, electrophoresis and/or high performance liquid chromatography. Relative lipophilicities were determined for the complexes by octanol-to-water extractions. Animal studies using mice indicated there was an inverse relationship between the octanol-to-water extraction ratio and urinary excretion. Two of the complexes having relatively high octanol-to-water extraction ratios were significantly excreted by the hepatobiliary system with localization in the gall bladder. The complex having the highest octanol-to-water ratio was not excreted significantly by the hepatobiliary system, but cleared very slowly from the blood and localized in the liver, lungs, spleen and to some extent the heart. Derivatization of cyclam can be performed without greatly reducing its ability to complex Tc but greatly influencing the biological distribution of its Tc complex. This indicates that there is a potential for preparing radiodiagnostic agents using macrocyclic tetraaza ligands

  6. Rational design of azide-bridged bimetallic complexes. Crystal structure and magnetic properties of Fe(III)MFe(III) (M = Ni(II) and Cu(II)) trinuclear species.

    Science.gov (United States)

    Colacio, Enrique; Costes, Jean-Pierre; Domínguez-Vera, José M; Maimoun, Ikram Ben; Suárez-Varela, José

    2005-01-28

    The first examples of azide-bridged bimetallic trinuclear complexes ([M(cyclam)][FeL(N3)(mu1,5-N3)]2) (H2L = 4,5-dichloro-1,2-bis(pyridine-2-carboxamido) benzene) have been structurally and magnetically characterized.

  7. A serials of sandwich-like trinuclear and one-dimensional chain cyanide-bridged iron(III)-copper(II) complexes: Syntheses, crystal structures and magnetic properties

    Science.gov (United States)

    Shi, Jingwen; Lan, Wenlong; Ren, Yanjie; Liu, Qingyun; Liu, Hui; Dong, Yunhui; Zhang, Daopeng

    2018-04-01

    Four pyridinecarboxamide trans-dicyanideiron(III) building blocks and one macrocyclic copper(II) compound have been employed to assemble cyanide-bridged heterometallic complexes, resulting in a serials of cyanide-bridged FeIII-CuII complexes with different structure types. The series of complexes can be formulated as: {[Cu(Cyclam)][Fe(bpb)(CN)2]2}·4H2O (1), {{[Cu(Cyclam)][Fe(bpb)(CN)2]}ClO4}n·nH2O (2), and {[Cu(Cyclam)][Fe(bpmb)(CN)2]2}·4H2O (3), {[Cu(Cyclam)][Fe(bpClb)(CN)2]2}·4H2O (4) and {{[Cu(Cyclam)][Fe(bpdmb)(CN)2]}ClO4}n·2nCH3OH (5) (bpb2- = 1,2-bis(pyridine-2-carboxamido)benzenate, bpmb2- = 1,2-bis(pyridine-2-carboxamido)-4-methyl-benzenate, bpClb2- = 1,2-bis(pyridine-2-carboxamido)-4-chloro-benzenate, bpdmb2- = 1,2-bis(pyridine-2-carboxamido)-4,5-dimethyl-benzenate, Cyclam = 1,4,8,11-tetraazacyclotetradecane). All the complexes have been characterized by elemental analysis, IR spectra and structural determination. Single X-ray diffraction analysis shows the similar neutral sandwich-like structures for complexes 1, 3 and 4, in which the two cyano precursors acting as monodentate ligand through one of their two cyanide groups were coordinated face to face to central Cu(II) ion. The complexes 2 and 5 can be structurally characterized as one-dimensional cationic single chain consisting of alternating units of [Cu(Cyclam)]2+ and [Fe(bpb/bpdmb)(CN)2]- with free ClO4- as balanced anion. Investigation over magnetic properties of the whole serials of complexes reveals the antiferromagnetic magnetic coupling between the neighboring cyanide-bridged Fe(III) and Cu(II) ions in complexes 3 and 4 and the ferromagnetic interaction in complexes 1, 2 and 5, respectively.

  8. Heterobimetallic coordination polymers involving 3d metal complexes and heavier transition metals cyanometallates

    Energy Technology Data Exchange (ETDEWEB)

    Peresypkina, Eugenia V. [Nikolaev Institute of Inorganic Chemistry, SB RAS, Novosibirsk 630090 (Russian Federation); Samsonenko, Denis G. [Nikolaev Institute of Inorganic Chemistry, SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Vostrikova, Kira E., E-mail: vosk@niic.nsc.ru [Nikolaev Institute of Inorganic Chemistry, SB RAS, Novosibirsk 630090 (Russian Federation); LMI, Université Claude Bernard Lyon 1, 69622 Villeurbanne Cedex (France)

    2015-04-15

    The results of the first steps in the design of coordination polymers based on penta- and heptacyanometallates of heavier d transitions metals are presented. The 2D structure of the coordination polymers: [(Mn(acacen)){sub 2}Ru(NO)(CN){sub 5}]{sub n} and two complexes composed of different cyanorhenates, [Ni(cyclam)]{sub 2}[ReO(OH)(CN){sub 4}](ClO{sub 4}){sub 2}(H{sub 2}O){sub 1.25} and [Cu(cyclam)]{sub 2}[Re(CN){sub 7}](H{sub 2}O){sub 12}, was confirmed by single crystal XRD study, the rhenium oxidation state having been proved by the magnetic measurements. An amorphism of [M(cyclam)]{sub 3}[Re(CN){sub 7}]{sub 2} (M=Ni, Cu) polymers does not allow to define strictly their dimensionality and to model anisotropic magnetic behavior of the compounds. However, with high probability a honey-comb like layer structure could be expected for [M(cyclam)]{sub 3}[Re(CN){sub 7}]{sub 2} complexes, studied in this work, because such an arrangement is the most common among the bimetallic assemblies of hexa- and octacyanometallates with a ratio [M(cyclam)]/[M(CN){sub n}]=3/2. For the first time was prepared and fully characterized a precursor (n-Bu{sub 4}N){sub 2}[Ru(NO)(CN){sub 5}], soluble in organic media. - Graphical abstract: The very first results in the design of 2D coordination polymers based on penta- and heptacyanometallates of 4d and5d transitions metals are presented. - Highlights: • Design of coordination polymers based on penta- and heptacyanometallates. • New Ru and Re cyanide based heterobimetallic coordination complexes. • Hydrolysis and ox/red processes involving [Re(CN){sub 7}]{sup 3+} during crystallization. • High magnetic anisotropy of [M(cyclam)]{sub 3}[Re(CN){sub 7}]{sub 2}(H{sub 2}O){sub n}, M=Cu, Ni, complexes.

  9. Recent results in muonium solution kinetics

    International Nuclear Information System (INIS)

    Jean, Y.C.; Ito, Y.; Stadlbauer, J.M.; Ng, B.W.; Walker, D.C.

    1983-06-01

    Using muonium spin rotation (MSR) techniques the aqueous solution kinetics of several muonium addition reactions and spin conversion interactions have been studied. The addition reactions show both diffusion and activation-controlled reaction rates with isotope effects between 1 and 3 for diffusion-control and between 7 and 31 for activation-control reactions. Barrier energies are typically approximately 15 kJ/mole and approximately 30 kJ/mole, respectively, for these processes in water. Spin-conversion interactions involving Ni +2 (aq) and Ni(cyclam) +2 complexes showed that spin-conversion of 'triplet' Mu by a paramagnetic solute occurs at or near the diffusion-controlled limit while the chemical reaction with the diamagnetic configuration of Ni(cyclam) +2 occurred some 100 times slower at ksub(M) 18 M -1 s -1

  10. Sensory profile and acceptability for pitanga (Eugenia uniflora L.) nectar with different sweeteners.

    Science.gov (United States)

    Freitas, Mírian Luisa Faria; Dutra, Mariana Borges de Lima; Bolini, Helena Maria André

    2016-12-01

    The objective of this study was to evaluate the sensory properties and acceptability of pitanga nectar samples prepared with sucrose and different sweeteners (sucralose, aspartame, stevia with 40% rebaudioside A, stevia with 95% rebaudioside A, neotame, and a 2:1 cyclamate/saccharin blend). A total of 13 assessors participated in a quantitative descriptive analysis and evaluated the samples in relation to the descriptor terms. The acceptability test was carried out by 120 fruit juice consumers. The results of the quantitative descriptive analysis of pitanga nectar showed that samples prepared with sucralose, aspartame, and the 2:1 cyclamate/saccharin blend had sensory profiles similar to that of the sample prepared with sucrose. Consumers' most accepted samples were prepared with sucrose, sucralose, aspartame, and neotame. The sweeteners that have the greatest potential to replace sucrose in pitanga nectar are sucralose and aspartame. © The Author(s) 2016.

  11. Risque dû à la consommation des boissons rafraichissantes sans ...

    African Journals Online (AJOL)

    Les résultats obtenus montrent que 36.66% des échantillons sont non conformes à la réglementation Algérienne. 23.33% sont ... 23.33% are concerning a chemical quality (the exceed of the doses of saccharin for 20% of samples and presence of a Sweetener no permit, the cyclamate in one sample) and 13.33% related to ...

  12. Olfactory sensitivity in CD-1 mice for the sperm-attractant odorant bourgeonal and some of its structural analogues

    OpenAIRE

    Larsson, Linda

    2010-01-01

    Using a conditioning paradigm and an automated olfactometer, I investigated the olfactory sensitivity of five CD-1 mice for seven aromatic aldehydes. With two of the stimuli (3-phenylpropanal and canthoxal), the animals discriminated concentrations as low as 10 ppb (parts per billion) from the odorless solvent and with four of the stimuli (helional, cyclamal, lilial and lyral) they discriminated concentrations as low as 1 ppb, with single individuals even scoring better. All five animals yiel...

  13. Micro‑cantilevers for optical sensing of biogenic amines

    DEFF Research Database (Denmark)

    Wang, Ying; Bravo Costa, Carlos André; Sobolewska, Elżbieta Karolina

    2017-01-01

    molecules in the gas phase. Different functionalization conditions were investigated by immersing gold coated AFM cantilevers in cyclam solutions at different concentrations, for different functionalization times, and for different post-annealing treatments. The optimum morphology for high capture...... micro-cantilever based mass detection. We demonstrate that besides conventional AFM systems a MEMS cantilever in combination with an optical read out is a powerful analytic system which is highly attractive for widespread use in diagnostic applications, with optimized functionalization conditions...

  14. Synthesis and antimalarial activity of metal complexes of cross-bridged tetraazamacrocyclic ligands.

    Science.gov (United States)

    Hubin, Timothy J; Amoyaw, Prince N-A; Roewe, Kimberly D; Simpson, Natalie C; Maples, Randall D; Carder Freeman, TaRynn N; Cain, Amy N; Le, Justin G; Archibald, Stephen J; Khan, Shabana I; Tekwani, Babu L; Khan, M O Faruk

    2014-07-01

    Using transition metals such as manganese(II), iron(II), cobalt(II), nickel(II), copper(II), and zinc(II), several new metal complexes of cross-bridged tetraazamacrocyclic chelators namely, cyclen- and cyclam-analogs with benzyl groups, were synthesized and screened for in vitro antimalarial activity against chloroquine-resistant (W2) and chloroquine-sensitive (D6) strains of Plasmodium falciparum. The metal-free chelators tested showed little or no antimalarial activity. All the metal complexes of the dibenzyl cross-bridged cyclam ligand exhibited potent antimalarial activity. The Mn(2+) complex of this ligand was the most potent with IC50s of 0.127 and 0.157μM against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) P. falciparum strains, respectively. In general, the dibenzyl hydrophobic ligands showed better anti-malarial activity compared to the activity of monobenzyl ligands, potentially because of their higher lipophilicity and thus better cell penetration ability. The higher antimalarial activity displayed by the manganese complex for the cyclam ligand in comparison to that of the cyclen, correlates with the larger pocket of cyclam compared to that of cyclen which produces a more stable complex with the Mn(2+). Few of the Cu(2+) and Fe(2+) complexes also showed improvement in activity but Ni(2+), Co(2+) and Zn(2+) complexes did not show any improvement in activity upon the metal-free ligands for anti-malarial development. Published by Elsevier Ltd.

  15. Suitability of artificial sweeteners as indicators of raw wastewater contamination in surface water and groundwater.

    Science.gov (United States)

    Tran, Ngoc Han; Hu, Jiangyong; Li, Jinhua; Ong, Say Leong

    2014-01-01

    There is no quantitative data on the occurrence of artificial sweeteners in the aquatic environment in Southeast Asian countries, particularly no information on their suitability as indicators of raw wastewater contamination on surface water and groundwater. This study provided the first quantitative information on the occurrence of artificial sweeteners in raw wastewater, surface water and groundwater in the urban catchment area in Singapore. Acesulfame, cyclamate, saccharin, and sucralose were ubiquitous in raw wastewater samples at concentrations in the range of ng/L-μg/L, while other sweeteners were not found or found only in a few of the raw wastewater samples. Residential and commercial effluents were demonstrated to be the two main sources of artificial sweeteners entering the municipal sewer systems. Relatively higher concentrations of the detected sweeteners were frequently found in surface waters at the sampling sites located in the residential/commercial areas. No significant difference in the concentrations of the detected sweeteners in surface water or groundwater was noted between wet and dry weather conditions (unpaired T-test, p> 0.05). Relatively higher concentrations and detection frequencies of acesulfame, cyclamate and saccharin in surface water samples were observed at the potentially impacted sampling sites, while these sweeteners were absent in most of the background surface water samples. Similarly, acesulfame, cyclamate, and saccharin were found in most groundwater samples at the monitoring well (GW6), which is located close to known leaking sewer segment; whereas these were absent in the background monitoring well, which is located in the catchment with no known wastewater sources. Taken together, the results suggest that acesulfame, cyclamate, and saccharin can be used as potential indicators of raw wastewater contamination in surface water and groundwater. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. The influence of ligand field effects on the magnetic exchange of high-spin Co(II)-semiquinonate complexes.

    Science.gov (United States)

    Bencini, Alessandro; Beni, Alessandra; Costantino, Ferdinando; Dei, Andrea; Gatteschi, Dante; Sorace, Lorenzo

    2006-02-07

    [Co(Me(4)cyclam)(tropolonate)](PF(6)) was synthesised and structurally characterised. Its electronic and W-band EPR spectra have been analysed by means of the angular overlap calculation of the Spin Hamiltonian parameters that provided also a satisfactory reproduction of the temperature dependence of the magnetic susceptibility. The present results can be interpreted assuming a pseudo-octahedral character for the Co(II) center. This prompted us to reconsider the model formerly used for the analysis of the magnetic coupling between hs-Co(II) and the paramagnetic o-semiquinonate ligand in the corresponding derivatives [Co(Me(4)cyclam)(PhenSQ)](PF(6)) and [Co(Me(4)cyclam)(DTBSQ)](PF(6)). These results indicate that the effect of the magnetic coupling is active only below 50 K and that a more refined model of exchange coupling between Co(II) and semiquinonato ligands is needed to quantitatively analyze the magnetic behaviour of this class of systems.

  17. Application of Liquid Chromatography-Tandem Mass Spectrometry To Determine Urinary Concentrations of Five Commonly Used Low-Calorie Sweeteners: A Novel Biomarker Approach for Assessing Recent Intakes?

    Science.gov (United States)

    Logue, Caomhan; Dowey, Le Roy C; Strain, J J; Verhagen, Hans; McClean, Stephen; Gallagher, Alison M

    2017-06-07

    Although the use of low-calorie sweeteners (LCSs) is widespread, methods of assessing consumption within free-living populations have inherent limitations. Five commonly consumed LCSs, namely, acesulfame-K, saccharin, sucralose, cyclamate, and steviol glycosides, are excreted via the urine, and therefore a urinary biomarker approach may provide more objective LCS intake data. A LC-ESI-MS/MS method of simultaneously determining acesulfame-K, saccharin, sucralose, cyclamate, and the excretory metabolite of steviol glycosides, steviol glucuronide, in human urine was developed and validated. Linearity was observed over a concentration range of 10-1000 ng/mL with coefficients of determination ranging from 0.9969 to 0.9997. Accuracy ranged from 92 to 104%, and intrabatch and interday precisions were within acceptable limits with %CV below 8% for all compounds. A double-blind, randomized crossover dose-response study was conducted to assess the usefulness of urinary LCS excretions (from both fasting spot and a full 24-h urine collection) for investigating recent intakes. Both modes of sampling were useful for distinguishing between the three short-term intakes of acesulfame-K, saccharin, cyclamates, and steviol glycosides (p biomarker approach may be useful for assessing intakes of five commonly consumed LCSs.

  18. Technetium complexation by macrocyclic compounds

    International Nuclear Information System (INIS)

    Li Fan Yu.

    1983-01-01

    Research in nuclear medicine are directed towards the labelling of biological molecules, however, sup(99m)Tc does not show sufficient affinity for these molecules. The aim of this study was to evaluate the ability of macrocyclic compounds to bind strongly technetium in order to be used as complexation intermediate. The reducing agents used were a stannous complex and sodium dithionite. Cryptates and polyesters are not good complexing agents. They form two complexes: a 2:1 sandwich complex or 3:2 and a 1:1 complex. Cyclams are good complexing agents for technetium their complexations strength was determined by competition with pyrophosphate, gluconate and DTPA. Using the method of ligand exchange, the oxidation state of technetium in the Tc-cyclam complex was IV or V. They are 1:1 cationic complexes, the complex charge is +1. The biodistribution in rats of labelling solutions containing (cyclam 14 ane N 4 ) C 12 H 25 shows a good urinary excretion without intoxication risks [fr

  19. Selected Micropollutants as Indicators in a Karst Catchment

    Science.gov (United States)

    Zirlewagen, Johannes; Schiperski, Ferry; Hillebrand, Olav; Nödler, Karsten; Licha, Tobias; Scheytt, Traugott

    2015-04-01

    High flow dynamics and variations in water quality are typical for karst springs and reflect the complex interaction of different flow and storage components within a karst system. Event-based monitoring of mobile micropollutants in spring water combined with information on their input is used (1) to quantify the impact of certain contamination scenarios on spring water quality and (2) to gain additional information on the intrinsic characteristics of a karst system. We employ the artificial sweeteners acesulfame and cyclamate as source specific indicators for sewage along with the herbicides atrazine and isoproturon for agriculture. The study site is the 45 km² rural catchment of the perennial karst spring Gallusquelle in SW-Germany (mean discharge: 0.5 m³/s). Overflow events of a stormwater detention basin (SDB, combined sewer system) are known to impact water quality. Most of the sewer system is situated in the SW of the catchment. Most agricultural land is found in the NE. Neither atrazine nor significant amounts of isoproturon were detected in wastewater. Concentrations and mass fluxes of acesulfame and cyclamate in wastewater were determined. The combined evaluation of the persistent compound acesulfame with the rather degradable cyclamate allows for the distinction of long and short transit times and thus slow and fast flow components. The same applies for atrazine (persistent) and isoproturon (degradable). In Germany, acesulfame was licensed in 1990, atrazine was banned shortly after, in 1991. During low flow conditions only atrazine (max. 4 ng/L) and acesulfame (max. 20 ng/L) were detected in spring water. After a recharge event without SDB overflow concentrations as well as mass fluxes of both compounds decreased, reflecting an increasing portion of event water in spring discharge. A breakthrough of isoproturon (max. 9 ng/L) indicated the arrival of water from croplands. After a recharge event accompanied by a SDB overflow cyclamate was detected at max

  20. Coordination functionalization of graphene oxide with tetraazamacrocyclic complexes of nickel(II): Generation of paramagnetic centers

    Energy Technology Data Exchange (ETDEWEB)

    Basiuk, Vladimir A., E-mail: basiuk@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Circuito Exterior C.U., 04510 México D.F. (Mexico); Department of Chemistry,Tufts University, 62 Talbot Avenue, Medford, MA 02155 (United States); Alzate-Carvajal, Natalia [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Circuito Exterior C.U., 04510 México D.F. (Mexico); Henao-Holguín, Laura V. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Circuito Exterior C.U., 04510 México D.F. (Mexico); Rybak-Akimova, Elena V. [Department of Chemistry,Tufts University, 62 Talbot Avenue, Medford, MA 02155 (United States); Basiuk, Elena V., E-mail: elbg1111@gmail.com [Department of Chemistry,Tufts University, 62 Talbot Avenue, Medford, MA 02155 (United States); Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Circuito Exterior C.U., 04510 México D.F. (Mexico)

    2016-05-15

    Highlights: • [Ni(cyclam)]{sup 2+} and [Ni(tet b)]{sup 2+} cations coordinate to carboxylic groups of GO. • The coordination takes place under basic conditions in aqueous-based medium. • The coordination results in the conversion from low-spin to high-spin Ni(II). • Functionalized GO samples were characterized by various instrumental techniques. - Abstract: We describe a novel approach to functionalization of graphene oxide (GO) which allows for a facile generation of paramagnetic centers from two diamagnetic components. Coordination attachment of [Ni(cyclam)]{sup 2+} or [Ni(tet b)]{sup 2+} tetraazamacrocyclic cations to carboxylic groups of GO takes place under basic conditions in aqueous-based reaction medium. The procedure is very straightforward and does not require high temperatures or other harsh conditions. Changing the coordination geometry of Ni(II) from square-planar tetracoordinated to pseudooctahedral hexacoordinated brings about the conversion from low-spin to high-spin state of the metal centers. Even though the content of tetraazamacrocyclic complexes in functionalized GO samples was found to be relatively low (nickel content of ca. 1 wt%, as determined by thermogravimetric analysis, elemental analysis and energy dispersive X-ray spectroscopy), room temperature magnetic susceptibility measurements easily detected the appearance of paramagnetic properties in GO + [Ni(cyclam)] and GO + [Ni(tet b)] nanohybrids, with effective magnetic moments of 1.95 BM and 2.2 BM for, respectively. According to density functional theory calculations, the main spin density is localized at the macrocyclic complexes, without considerable extension to graphene sheet, which suggests insignificant ferromagnetic coupling in the nanohybrids, in agreement with the results of magnetic susceptibility measurements. The coordination attachment of Ni(II) tetraazamacrocycles to GO results in considerable changes in Fourier-transform infrared and X-ray photoelectron spectra

  1. The binding site for neohesperidin dihydrochalcone at the human sweet taste receptor

    Directory of Open Access Journals (Sweden)

    Kratochwil Nicole A

    2007-10-01

    Full Text Available Abstract Background Differences in sweet taste perception among species depend on structural variations of the sweet taste receptor. The commercially used isovanillyl sweetener neohesperidin dihydrochalcone activates the human but not the rat sweet receptor TAS1R2+TAS1R3. Analysis of interspecies combinations and chimeras of rat and human TAS1R2+TAS1R3 suggested that the heptahelical domain of human TAS1R3 is crucial for the activation of the sweet receptor by neohesperidin dihydrochalcone. Results By mutational analysis combined with functional studies and molecular modeling we identified a set of different amino acid residues within the heptahelical domain of human TAS1R3 that forms the neohesperidin dihydrochalcone binding pocket. Sixteen amino acid residues in the transmembrane domains 2 to 7 and one in the extracellular loop 2 of hTAS1R3 influenced the receptor's response to neohesperidin dihydrochalcone. Some of these seventeen residues are also part of the binding sites for the sweetener cyclamate or the sweet taste inhibitor lactisole. In line with this observation, lactisole inhibited activation of the sweet receptor by neohesperidin dihydrochalcone and cyclamate competitively, whereas receptor activation by aspartame, a sweetener known to bind to the N-terminal domain of TAS1R2, was allosterically inhibited. Seven of the amino acid positions crucial for activation of hTAS1R2+hTAS1R3 by neohesperidin dihydrochalcone are thought to play a role in the binding of allosteric modulators of other class C GPCRs, further supporting our model of the neohesperidin dihydrochalcone pharmacophore. Conclusion From our data we conclude that we identified the neohesperidin dihydrochalcone binding site at the human sweet taste receptor, which overlaps with those for the sweetener cyclamate and the sweet taste inhibitor lactisole. This readily delivers a molecular explanation of our finding that lactisole is a competitive inhibitor of the receptor

  2. A high-throughput headspace gas chromatographic technique for the determination of nitrite content in water samples.

    Science.gov (United States)

    Zhang, Shu-Xin; Peng, Rong; Jiang, Ran; Chai, Xin-Sheng; Barnes, Donald G

    2018-02-23

    This paper reports on a high-throughput headspace gas chromatographic method (HS-GC) for the determination of nitrite content in water sample, based on GC measurement of cyclohexene produced from the reaction between nitrite and cyclamate in a closed vial. The method has a relative standard deviation of water samples. In short, the present HS-GC method is simple, accurate, and sensitive, and it is very suitable to be used in the batch sample testing. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. A study of the complexation of [99mTcO2+] by 2,4-dioxo-1,5,8,12-tetraazacyclotetradecane, 2-oxo-1,5,8,12-tetraazacyclotetradecane and their methylated derivatives in position 3

    International Nuclear Information System (INIS)

    Riche, F.; Vidal, M.; Pasqualini, R.; Duatti, A.

    1992-01-01

    The kinetics of complexation of TcO 2 + by 2,4-dioxo-1,5,8,12-tetraazacyclotetradecane, 2-oxo-1,5,8,12-tetraazacyclotetradecane and their methylated derivatives were studied by reducing 99m TcO 4 - with stannous tartrate. The charges of the complexes obtained were studied by electrophoresis; equilibration studies of the complexes with cyclam and a comparative study of the complexation kinetics have served to demonstrate the remarkable kinetic stability of [1,4,8,11-tetraazacyclotetradecane-TcO 2 + ] and [2-oxo-1,5,8,12-tetraazacyclotetradecane-TcO 2 + ]. (author)

  4. LDRD final report on "Pumping up CO2 and conversion into useful molecules" (LDRD 105932).

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, Richard Alan; Stewart, Constantine A.; Dickie, Diane A. (University of New Mexico, Albuquerque, NM)

    2009-11-01

    Group 12 metal cyclam complexes and their derivatives as well as (octyl){sub 2}Sn(OMe){sub 2} were examined as potential catalysts for the production of dimethyl carbonate (DMC) using CO{sub 2} and methanol. The zinc cyclams will readily take up carbon dioxide and methanol at room temperature and atmospheric pressure to give the metal methyl carbonate. The tin exhibited an improvement in DMC yields. Studies involving the reaction of bis-phosphino- and (phosphino)(silyl)-amido group 2 and 12 complexes with CO{sub 2} and CS{sub 2} were performed. Notable results include formation of phosphino-substituted isocyanates, fixation of three moles of CO{sub 2} in an unprecedented [N(CO{sub 2}){sub 3}]{sup 3-} anion, and rapid splitting of CS{sub 2} by main group elements under extremely mild conditions. Similar investigations of divalent group 14 silyl amides led to room temperature splitting of CO{sub 2} into CO and metal oxide clusters, and the formation of isocyanates and carbodiimides.

  5. Time-intensity profile of pitanga nectar (Eugenia uniflora L.) with different sweeteners: Sweetness and bitterness.

    Science.gov (United States)

    Freitas, Mírian Luisa Faria; de Lima Dutra, Mariana Borges; Bolini, Helena Maria André

    2016-01-01

    Pitanga has been used by the Brazilian food industry mainly for juice production. This fruit shows good economic potential due to its high concentration of vitamins and minerals. The aim of the present work was to characterize the time-intensity profile of pitanga nectar sweetened with different sweeteners to verify differences on the perception of sweet and bitter tastes. The sweeteners used to replace sucrose were sucralose, aspartame, stevia 40% rebaudioside A, stevia 95% rebaudioside A, neotame, and 2:1 cyclamate/saccharin blend. Fifteen assessors were selected according to their discriminating capability and trained to participate in the time-intensity analysis for sweetness and bitterness. The samples prepared with sucralose and 2:1 cyclamate/saccharin blend presented a similar sweetness profile to the sample prepared with sucrose, and the samples prepared with sucralose and aspartame presented a similar bitterness profile to the sample prepared with sucrose. Thus, sucralose would be the most suitable sweetener to replace sucrose in pitanga nectar. © The Author(s) 2015.

  6. The in vivo behavior of copper-64-labeled azamacrocyclic complexes

    International Nuclear Information System (INIS)

    Jones-Wilson, Teresa M.; Deal, Kim A.; Anderson, Carolyn J.; McCarthy, Deborah W.; Kovacs, Zoltan; Motekaitis, Ramunas J.; Sherry, A. Dean; Martell, Arthur E.; Welch, Michael J.

    1998-01-01

    The use of copper radioisotopes in imaging and therapy applications has created a greater need for bifunctional chelates (BFCs) for complexing copper radioisotopes to biomolecules. It has been demonstrated that the charge and lipophilicity of the Cu-BFC complex has a significant effect on the in vivo behavior of the radiolabeled Cu-BFC-biomolecule conjugate. To evaluate the effects of charge, stability, and macrocyclic backbone size on the biological behavior of 64 Cu complexes, a series of macrocyclic 64 Cu complexes have been prepared, and the biodistributions of these agents were evaluated in normal Sprague-Dawley rats. Two macrocyclic backbones, dodecane and tetradecane, were evaluated; cyclen, DOTA, and DO2A were dodecane backbone derivatives, and cyclam, TETA, and et-cyclam were tetradecane backbone derivatives. The biodistributions of the 64 Cu-labeled complexes correlated with differences in the size of the macrocycle backbone and the formal charge of the complex. All compounds showed uptake and clearance through the liver and kidneys; however, the positively charged 64 Cu complexes showed significantly higher uptake in both of these organs than did the negatively charged or neutral complexes. 64 Cu-TETA, a negatively charged complex with the tetradecane backbone, had the most efficient clearance by 24 hours' postinjection. These data suggest that negatively charged complexes may have more favorable clearance properties when used as BFCs

  7. The effect of heterocyclic S,S’-ligands on the electrochemical properties of some cobalt(III complexes in acid

    Directory of Open Access Journals (Sweden)

    V. M. JOVANOVIC

    2005-02-01

    Full Text Available Eight mixed-ligand cobalt(III complexes with the macrocyclic amine 1,4,8,11-tetraazacyclotetradecane (cyclam and a heterocyclic dithiocarbamate (Rdtc- i.e., morpholine- (Morphdtc, thiomorpholine- (Timdtc, piperazine- (Pzdtc, N-methylpiperazine-(Mepzdtc, piperidine- (Pipdtc, 2-, 3- or 4-methylpiperidine- (2-, 3- and 4-Mepipdtc carbodithionato-S,S ions, of the general formula [Co(cyclamRdtc](ClO42, were investigated in deoxygenated 0.1MHClO4 solutions. Cyclic voltammetry data at a glassy carbon (GC electrode demonstrate a redox reaction of cobalt(III from the complexes at potentials strongly influenced by the presence of different heterocyclic Rdtc- ligands. In this respect, the complexes were separated into two groups: the first, with a heteroatom O, S or N in the heterocyclic ring, and the second, with a methyl group on the piperidine ring of the Rdtc- ligand. Anodic polarization of an Fe electrode in the presence of the complexes shows their influence not only on the dissolution of iron but also on the hydrogen evolution reactions and on this basis complexes the complexes could be divided into the same two groups. It was found that the weaker the inhibiting effect of the free heterocyclic amines is, the significantly higher is the efficiency of the corresponding complexes.

  8. 1,4,8,11-Tetra[2-aryl-1-diazenyl]-1,4,8,11-tetraazacyclotetradecanes - synthesis, characterization, and x-ray crystallography of the first tetrakistriazenes to be reported

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, J.D.; Vaughan, K. [Dept. of Chemistry, Saint Mary' s Univ., Halifax, Nova Scotia (Canada)], E-mail: keith.vaughan@smu.ca; Bertolasi, V. [Dipartimento di Chimica and Centro di Strutturistica Diffrattometrica, Universita' di Ferrara, Ferrara (Italy)

    2006-10-15

    The reactions of a series of arene diazonium salts with 1,4,8,11-tetraazacyclotetradecane (cyclam) afford the novel compounds, the 1,4,8,11-tetra[2-aryl-1-diazenyl]-1,4,8,11-tetraazacyclotetradecanes (1a-1f), which are the first examples of tetrakistriazenes to be reported. The tetrakistriazenes were characterized by IR spectroscopy, proton and carbon NMR, elemental analysis, high resolution electrospray mass spectrometry, and X-ray crystallography. The analogous reaction of a diazonium salt with 1,4,7-triazacyclononane or 1,5,9-triazacyclododecane yields the tristriazenes 2, 3a, and 3b. The structures of compounds 1c and 1e were solved by X-ray crystallography at low temperature (150 K). Both molecules display a conformation where the four phenyltriazenyl groups point alternately upwards and downwards with respect to the mean macrocyclic plane. (author)

  9. 1,4,8,11-Tetra[2-aryl-1-diazenyl]-1,4,8,11-tetraazacyclotetradecanes - synthesis, characterization, and x-ray crystallography of the first tetrakistriazenes to be reported

    International Nuclear Information System (INIS)

    Clarke, J.D.; Vaughan, K.; Bertolasi, V.

    2006-01-01

    The reactions of a series of arene diazonium salts with 1,4,8,11-tetraazacyclotetradecane (cyclam) afford the novel compounds, the 1,4,8,11-tetra[2-aryl-1-diazenyl]-1,4,8,11-tetraazacyclotetradecanes (1a-1f), which are the first examples of tetrakistriazenes to be reported. The tetrakistriazenes were characterized by IR spectroscopy, proton and carbon NMR, elemental analysis, high resolution electrospray mass spectrometry, and X-ray crystallography. The analogous reaction of a diazonium salt with 1,4,7-triazacyclononane or 1,5,9-triazacyclododecane yields the tristriazenes 2, 3a, and 3b. The structures of compounds 1c and 1e were solved by X-ray crystallography at low temperature (150 K). Both molecules display a conformation where the four phenyltriazenyl groups point alternately upwards and downwards with respect to the mean macrocyclic plane. (author)

  10. Passion fruit juice with different sweeteners: sensory profile by descriptive analysis and acceptance.

    Science.gov (United States)

    Rocha, Izabela Furtado de Oliveira; Bolini, Helena Maria André

    2015-03-01

    This study evaluated the effect of different sweeteners on the sensory profile, acceptance, and drivers of preference of passion fruit juice samples sweetened with sucrose, aspartame, sucralose, stevia, cyclamate/saccharin blend 2:1, and neotame. Sensory profiling was performed by 12 trained assessors using quantitative descriptive analysis (QDA). Acceptance tests (appearance, aroma, flavor, texture and overall impression) were performed with 124 consumers of tropical fruit juice. Samples with sucrose, aspartame and sucralose showed similar sensory profile (P Passion fruit flavor affected positively and sweet aftertaste affected negatively the acceptance of the samples. Samples sweetened with aspartame, sucralose, and sucrose presented higher acceptance scores for the attributes flavor, texture, and overall impression, with no significant (P passion fruit juice.

  11. Avaliação sensorial, microbiologia e físico-química de suco artificial de laranja adicionado de diferentes agentes adoçantes

    Directory of Open Access Journals (Sweden)

    Iago Felipe da Silva Leite

    2016-11-01

    Full Text Available Diante do aumento do consumo de adoçantes por vários fatores e a procura por uma dieta mais saudável,  para a redução dos riscos de doenças como, diabetes, obesidade, entre outras, este trabalho teve como objetivo avaliar a diferença da doçura e aceitação dos diferentes agentes adoçantes em sucos artificiais. Foram formulados sucos em pó sabor laranja e adicionado os diferentes agentes adoçantes (sacarose, demerara, stevia pura, sacarina sódica + ciclamato de sódio e sacarina sódica + ciclamato de sódio + stevia. Realizou-se analises de pH e de sólidos solúveis totais (ºBrix para as diferentes formulações, ocorrendo variações, além das análises microbiológicas para coliformes totais e Salmonella sp/25g, resultando em ausência para ambos Os resultados apontam que as amostras estão próprias para consumo segundo a legislação virgente. A análise foi aplicada no laboratório de análise sensorial da Universidade Federal de Campina Grande e avaliada por 93 provadores. Aplicou-se uma ficha sensorial levando em consideração a aceitação dos agentes adoçantes. Conclui-se que a sacarina sódica + ciclamato de sódio e sacarina sódica + ciclamato de sódio + stevia foi a formulação com maior índice de aprovação.SensoSensory, microbiological and physico-chemical evaluation of artificial orange juice added with different sweetening agents Abstract: The increase in the consumption of sweeteners by several factors. And the demand for a healthier diet with reduced risk of diseases such as, diabetes, obesity, among others, this study aimed to assess the degree of sweetness of difference and acceptance of different sweetening agents. Were formulated artificial juices powdered orange flavor and added different sweeteners (sucrose, demerara, pure stevia, saccharin + sodium cyclamate and sodium saccharin + sodium cyclamate + stevia. We conducted analysis of pH and total soluble solids (° Brix for the different

  12. Physical-chemical, caloric and sensory characterization of light jambolan (Syzygium cumini Lamarck jelly

    Directory of Open Access Journals (Sweden)

    Ellen Silva Lago-Vanzela

    2011-09-01

    Full Text Available In Brazil, several little economically explored fruits have good potential as raw material for the agro-industry. This study aimed to produce and determine the physical-chemical and sensory characteristics of light jambolan jelly. This fruit has intense purple color, which gave the jellies - both standard and light - a quite attractive visual aspect. The light jellies exhibited similar physical-chemical characteristics to the ones developed through the conventional method and; with the proportion of sweeteners used, the caloric values of the formulations were reduced to the range of 41 to 53%, attending the requirements of the Brazilian legislation for this type of product. The sensory profile obtained for the 4 light formulations developed, clearly showed the tasters' preference for the jelly elaborated with the association of cyclamate and saccharin. Thus, the results revealed good perspectives for the application of this fruit in the food industry.

  13. Molecular mechanism of AMD3100 antagonism in the CXCR4 receptor: transfer of binding site to the CXCR3 receptor

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; Gerlach, Lars-Ole; Jakobsen, Janus S

    2004-01-01

    , respectively. Metal ion binding in the cyclam rings of AMD3100 increased its dependence on Asp(262) and provided a tighter molecular map of the binding site, where borderline mutational hits became clear hits for the Zn(II)-loaded analog. The proposed binding site for AMD3100 was confirmed by a gradual build......-up in the rather distinct CXCR3 receptor, for which the compound normally had no effect. Introduction of only a Glu at position VII:06 and the removal of a neutralizing Lys residue at position VII:02 resulted in a 1000-fold increase in affinity of AMD3100 to within 10-fold of its affinity in CXCR4. We conclude...

  14. Artificial sweeteners in a large Canadian river reflect human consumption in the watershed.

    Directory of Open Access Journals (Sweden)

    John Spoelstra

    Full Text Available Artificial sweeteners have been widely incorporated in human food products for aid in weight loss regimes, dental health protection and dietary control of diabetes. Some of these widely used compounds can pass non-degraded through wastewater treatment systems and are subsequently discharged to groundwater and surface waters. Measurements of artificial sweeteners in rivers used for drinking water production are scarce. In order to determine the riverine concentrations of artificial sweeteners and their usefulness as a tracer of wastewater at the scale of an entire watershed, we analyzed samples from 23 sites along the entire length of the Grand River, a large river in Southern Ontario, Canada, that is impacted by agricultural activities and urban centres. Municipal water from household taps was also sampled from several cities within the Grand River Watershed. Cyclamate, saccharin, sucralose, and acesulfame were found in elevated concentrations despite high rates of biological activity, large daily cycles in dissolved oxygen and shallow river depth. The maximum concentrations that we measured for sucralose (21 µg/L, cyclamate (2.4 µg/L [corrected], and saccharin (7.2 µg/L are the highest reported concentrations of these compounds in surface waters to date anywhere in the world. Acesulfame persists at concentrations that are up to several orders of magnitude above the detection limit over a distance of 300 km and it behaves conservatively in the river, recording the wastewater contribution from the cumulative population in the basin. Acesulfame is a reliable wastewater effluent tracer in rivers. Furthermore, it can be used to assess rates of nutrient assimilation, track wastewater plume dilution, separate human and animal waste contributions and determine the relative persistence of emerging contaminants in impacted watersheds where multiple sources confound the usefulness of other tracers. The effects of artificial sweeteners on aquatic biota

  15. Pharmaceuticals and personal care products (PPCPs) and artificial sweeteners (ASs) in surface and ground waters and their application as indication of wastewater contamination.

    Science.gov (United States)

    Yang, Yuan-Yuan; Zhao, Jian-Liang; Liu, You-Sheng; Liu, Wang-Rong; Zhang, Qian-Qian; Yao, Li; Hu, Li-Xin; Zhang, Jin-Na; Jiang, Yu-Xia; Ying, Guang-Guo

    2018-03-01

    We systematically investigated the occurrence and distribution of 93 pharmaceuticals and personal care products (PPCPs) and 5 artificial sweeteners (ASs) in surface water and groundwater of Dongjiang River basin in south China. In surface water, 52 compounds were detected with median concentrations ranging from 0.06ng/L to 504ng/L, while in groundwater, 33 compounds were detected with concentrations up to 4580ng/L for acesulfame. PPCPs and ASs were widely detected in the surface water and groundwater samples, which indicated contamination by domestic wastewater in the surface water and groundwater of Dongjiang River basin. Temporal and spatial variations of the detected chemicals were observed in surface water. Acesulfame, sucralose and cyclamate can be used as wastewater indicators to imply contamination in groundwater caused by domestic wastewater due to their hydrophilicity, anthropogenic sources and ubiquity in groundwater. Moreover, the detection of the readily degradable ASs, cyclamate, was a strong indication of untreated wastewater in groundwater. Sucralose was found to be a suitable wastewater indicator to reflect domestic wastewater contamination in surface water and groundwater qualitatively and quantitatively, and it can be used to evaluate wastewater burden in surface water and groundwater of Dongjiang River basin. The wastewater burden data from this survey implied serious contamination in surface water and groundwater by domestic wastewater at Shima River, a tributary of the Dongjiang River. The findings from this study suggest that the selected labile and conservative chemicals can be used as indication of wastewater contamination for aquatic environments qualitatively and quantitatively. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. A survey on trace organic chemicals in a German water protection area and the proposal of relevant indicators for anthropogenic influences.

    Science.gov (United States)

    Seitz, Wolfram; Winzenbacher, Rudi

    2017-06-01

    A comprehensive monitoring programme of trace organic chemicals (TOrC) was conducted for a German water protection area in karstic ground. The aim of this survey was to detect the potential anthropogenic influences of point sources such as wastewater treatment plants and diffuse pollution such as runoff water from roads on the raw water used for drinking water treatment. The programme comprised seven sampling campaigns within 2 years each with up to 20 sampling sites. In total, the programme included 84 anthropogenic compounds from pharmaceuticals, iodinated X-ray contrast media, sweeteners, industrial chemicals (benzotriazoles, melamines and benzothiazoles) and pesticide metabolites. Cyclamate occurred with the highest median concentration of 44 μg l -1 in untreated wastewater and acesulfame occurred with a concentration of 20 μg l -1 in treated wastewater. In runoff water from roads, the most relevant compounds were tolyltriazole with 2.3 μg l -1 and the desphenyl-chloridazon with 1.2 μg l -1 . In the stream waters, the highest median concentrations were found for melamine and acesulfame both at 0.61 μg l -1 . High elimination during conventional wastewater treatment was observed for 5 out of 49 compounds. These are acetyl-sulfamethoxazole, aciclovir, cyclamate, ibuprofen and saccharin. Based on the survey results, we propose a set of nine compounds to be used as indicators for wastewater, untreated wastewater and runoff water from roads for an efficient surveillance. The indicators are intended to detect anthropogenic influences in surface, ground and drinking water.

  17. Avaliação sensorial de bebidas de goiaba adoçadas com diferentes agentes adoçantes Sensory evaluation of guava drinks sweetened with different sweetening agents

    Directory of Open Access Journals (Sweden)

    Aline Gurgel Fernandes

    2009-06-01

    Full Text Available Devido à crescente procura por bebidas à base de frutas tropicais e à expansão do segmento de produtos com valores calóricos reduzidos, este trabalho objetivou avaliar o grau de doçura, sabor, impressão global e a intenção de compra das bebidas de goiaba adoçadas com diferentes agentes adoçantes através de frequência de notas, teste de médias e Mapa de Preferência Interno (MPI. Utilizaram-se polpa de goiaba, água potável e diferentes agentes adoçantes (sacarose, mistura ciclamato/sacarina, aspartame, acesulfame-K, estévia e mistura sacarina/ciclamato sódico/acesulfame-K. A avaliação sensorial foi realizada com 100 provadores não treinados em teste laboratorial através do delineamento de blocos completos balanceados. Objetivando a avaliação das respostas individuais de cada provador, as respostas sensoriais foram avaliadas pela metodologia do MPI, empregando-se a técnica de Análise de Componentes Principais. As bebidas de goiaba adoçadas com sacarose e aspartame apresentaram avaliação sensorial semelhante por parte dos consumidores, apresentando os maiores valores médios no teste de aceitação, enquanto as adoçadas com estévia, com a mistura de três agentes adoçantes e a mistura ciclamato/sacarina apresentaram os valores mais baixos na avaliação sensorial. A utilização do MPI confirmou os resultados obtidos através de frequência de notas e teste de médias.Due to a constant search for tropical fruit drinks and calorie reduced products, this work aimed to evaluate the degree of sweetness, flavor, overall global impression, and purchase intention of guava drinks sweetened with different sweetening agents through the response rank frequency and average test, and internal preference mapping (IPM. Guava pulp, drinking water, and sweetening agents (sucrose, mixture cyclamate/saccharine, aspartame, acesulfame K, stevia and mixture saccharine/sodium cyclamate/acesulfame K were used. The sensory evaluation was

  18. Evaluating the environmental impact of artificial sweeteners: a study of their distributions, photodegradation and toxicities.

    Science.gov (United States)

    Sang, Ziye; Jiang, Yanan; Tsoi, Yeuk-Ki; Leung, Kelvin Sze-Yin

    2014-04-01

    While having a long tradition as safe food additives, artificial sweeteners are a newly recognized class of environmental contaminants due to their extreme persistence and ubiquitous occurrence in various aquatic ecosystems. Resistant to wastewater treatment processes, they are continuously introduced into the water environments. To date however, their environmental behavior, fate as well as long term ecotoxicological contributions in our water resources still remain largely unknown. As a first step in the comprehensive study of artificial sweeteners, this work elucidates the geographical/seasonal/hydrological interactions of acesulfame, cyclamate, saccharin and sucralose in an open coast system at an estuarine/marine junction. Higher occurrence of acesulfame (seasonal average: 0.22 μg L(-1)) and sucralose (0.05 μg L(-1)) was found in summer while saccharin (0.11  μg L(-1)) and cyclamate (0.10 μg L(-1)) were predominantly detected in winter. Seasonal observations of the four sweeteners suggest strong connections with the variable chemical resistance among different sweeteners. Our photodegradation investigation further projected the potential impact of persistent acesulfame and sucralose compounds under prolonged exposure to intensive solar irradiation. Real-time observation by UPLC-ESI/MS of the degradation profile in both sweeteners illustrated that formation of new photo by-products under prolonged UV irradiation is highly viable. Interestingly, two groups of kinetically behaved photodegradates were identified for acesulfame, one of which was at least six times more persistent than the parent compound. For the first time, acute toxicity for the degradates of both sweeteners were arbitrarily measured, revealing photo-enhancement factors of 575 and 17.1 for acesulfame and sucralose, respectively. Direct comparison of photodegradation results suggests that the phototoxicity of acesulfame degradation products may impact aquatic ecosystems. In an attempt

  19. PENGEMBANGAN METODE PENETAPAN KADAR SIKLAMAT BERBASIS KROMATOGRAFI CAIR KINERJA TINGGI GUNA DIIMPLEMENTASIKAN DALAM KAJIAN PAPARAN

    Directory of Open Access Journals (Sweden)

    Budi Wibowotomo

    2012-08-01

    Full Text Available The aim of this research was to develop a method for determining cycla­mate content in foods based on High Performance Liquid Chromatography for exposure assessment of cyclamate. The extraction procedure is conducted by de­creasing pH sample until less than 2, and mobile phase is executed by applying the ratio of phosphate buffer-methanol as 75:25, 80:20, 85:15. The results of experiments be obtained colom: ODS RP-18, 5 μm, 250 x 4,6 mm ID; mobile phase: phosphate buffer/KH2PO4 pH 4,6 and metanol in a ratio of 85:15; flow rate: 1 ml/min; injection volume: 20 μl; and detector: UV-Vis 200 nm. The indication of extraction showed by parameter distribution ratio D ≈ KD and the extraction efficiency of 83.04–94.92%. The exposure estimated of cyclamate based concentration analysis is about 28.41 mg/kg bw/day (258.27% ADI, where SNI 01-6993-2004 regulates 2.99 mg/kg bw/day (27.21% ADI. Tujuan penelitian adalah mengembangkan metode penetapan siklamat ber­basis kromatografi cair kinerja tinggi untuk pengukuran konsentrasi siklamat. Prose­dur  ekstraksi menggunakan  modifikasi  pH sampel hingga pH lebih kecil 2, dan fase gerak diterapkan perlakuan rasio bufer fosfat–metanol 75 : 25, 80 : 20, dan 85 : 15. Hasil eksperimen diperoleh kolom: ODS RP-18, 5 μm, 250 x 4,6 mm ID; fase gerak: bufer fosfat/KH2PO4 pH 4,6 dan metanol rasio 85 : 15; laju aliran: 1 ml/menit; volume injeksi: 20 μl; dan detektor: UV-Vis 200 nm. Indikasi keberhasilan ekstraksi ditunjukkan dengan parameter rasio distribusi D ≈ KD dan efisiensi ekstraksi 83,04–94,92%. Estimasi paparan berdasar konsentrasi analisis langsung sebesar 28,41 mg/kg bb/hari (258,27% ADI, sedang estimasi paparan berbasis SNI 01-6993-2004 sebesar 2,99 mg/kg bb/hari (27,21% ADI.

  20. [Compound preservative and cyclamat determinated by gas chromatography].

    Science.gov (United States)

    Xin, Ruozhu; Ding, Mei; Zheng, Xianguang; Li, Yajuan

    2008-07-01

    To establish a gas chromatography method for synchronous determination of six preservatives and cyclamat in cake and pastry. The pre-treatment of complicated compound was finished by dialysis cleaning technology. The interference of the complicated foundation body in the cake and pastry was removed by the best dialysis condition: 2 g/L NaOH of dialysis fluid was dialyzed at the temperature of 25 degrees C for 24h, and the six preservatives and cyclamat (sorbic acid, benzoic acid, dehydroacetic acid, ethylparabenum, propylparabenum, butylparabenun and sodium cyclamate) were synchronously seperated by 60-80 mesh Chromosorb WAW DMCS glass packing column of intercoated 5% DEGS + 1% H3 PO4. The seven components in the sample had a good lining relation at the concentration 100 -5000 mg/L when the external standard method was used, and their correlation coefficients were 0.9993-0.9998, and their average recovery rates were 87.5%-101.9%, and their relative standard deviations were 0.64%-3.3%, and detection limits were 1.1-8.8 mg/L. This method could be used to quickly analyse the compound preservatives of the large batch cake and pastry through the common gas chromatography and packed column and this method was simple, accurate and quick.

  1. The influence of synthetic food additives and surfactants on the body weight of larvae of Tenebrio molitor (Coleoptera, Tenebrionidae

    Directory of Open Access Journals (Sweden)

    V. O. Martynov

    2017-08-01

    Full Text Available The broad spectrum of negative effects of food additives and surfactants on living organisms and the environment in general indicate a necessity of a detailed study on this issue. The aim of this article is to evaluate the impact of food additives and surfactants in a concentration of 350 mg/kg of fodder on the body weight of third age Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae larvae. A significant change in the body weight of T. molitor larvae was observed when they consumed a diet containing 350 mg/kg of sodium glutamate, sodium cyclamate and sodium benzoate. We observed a tendency towards increase in body weight after addition of the food colouring Allura Red, saccharin, benzoic acid, betaine, emulsifying wax, AOS and SLES, and also we observed a decrease in body weight after addition of Tartrazine and Indigo Carmine in the same concentration. Out of the 18 tested food additives, 3 significantly stimulated an increase in the body weight of third age T. molitor larvae, and 3 manifested the same effect at the level of tendency (stimulated an increase in mass on average by 43–58% over the 14-day experiment, and 2 caused decrease in the body weight of larvae. Also, the 4 studied surfactants manifested a tendency towards increase in the body weight of T. molitor. This study on the impact of food additives and surfactants on organisms of insects is of great significance for protecting rare species of insects.

  2. Storage stability of standard and diet figs canned in syrup

    Directory of Open Access Journals (Sweden)

    Priscilla Kárim CAETANO

    Full Text Available Abstract The current study aimed to evaluate the physicochemical, microbiological and sensory quality of traditional and diet figs canned in syrup, as well as verify their storage stability. Therefore, it was used green figs from the cultivar Roxo de Valinhos. Two treatments were held: standard sucrose syrup and sweetener blends: sodium cyclamate, sucralose and sodium saccharin. The syrups were previously prepared; being 25 °Brix for sucrose syrup; and by dividing the quantity of sucrose potency (100 to the blend of sweeteners potency (125 for sweetener blends. The products were stored at room temperature for 180 days and evaluated once a month through pH, soluble solids, titratable acidity, texture, vacuum and sensory evaluation (i.e. affective test; except for the commercial sterility test that was conducted at 0 to 180 days. Both canned figs in syrup showed no significant difference for pH, titratable acidity, soluble solids, vacuum and texture; therefore, both were considered commercially sterile and kept their sensory characteristics throughout storage.

  3. Targeting CXCR4 in HIV Cell-Entry Inhibition

    DEFF Research Database (Denmark)

    Steen, Anne; Schwartz, T W; Rosenkilde, M M

    2010-01-01

    CXCR4 and CCR5 constitute the two major coreceptors for HIV-1 entry into host cells. In the course of an HIV-infection, a coreceptor switch takes place in approximately half of the patients - from R5 HIV-1 (CCR5 utilizing) strains to X4 HIV-1 (CXCR4 utilizing) strains. Treatment of HIV......-infected individuals with CXCR4 antagonists delays the onset of AIDS by preventing the CCR5 to CXCR4 coreceptor switch. In addition to the endogenous CXCR4 and CCR5 ligands, other chemokines, for example the human herpesvirus 8 encoded CC-chemokine, vCCL2, and modifications hereof, have proven efficient HIV-1 cell...... no oral bioavailability. The hunt for orally active small-molecule CXCR4 antagonists led to the development of monocyclam-based compounds, and recently to the non-cyclam antagonist AMD070, which is orally active and currently in Phase II clinical trial as anti-HIV treatment. Current review provides...

  4. Determination of essential elements in dietetic sample by neutron activation analysis; Determinacao de elementos essenciais em alimentos dieteticos pela tecnica de analise por ativacao com neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Siquelli, Murilo V.; Maihara, Vera A. Maihara [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Lab. de Analise por Ativacao Neutronica]. E-mail: murilo_siquelli@hotmail.com; vmaihara@ipen.br

    2005-07-01

    In the last years there has been an increase of the dietetic product consumption by people who suffer from diabetes, heart disease and by people concerned about having a healthy life as well. Despite the increase of dietetic product presents in the diet of the Brazilian population, the use of these products is still controversial. The analysis of the nutritional composition of these products is becoming important because a great number of people is changing their traditional food by dietetic products. In the literature, there is no information about the inorganic composition, mainly related to the essential elements, in the dietetic products: diet and light . In this study are presented preliminary results of the concentrations of Br, Ca, Cr, Fe, Na and Zn determined by Instrumental Neutron Activation Analysis in aspartame, saccharin and cyclamate sodium , and stevia based sweetener samples. Gelatin samples, diet and light, were also analyzed. Methodology validation was done analyzing NIST reference materials Tea Leaves (INCT-TL-1) and Mixed Polish Herbs (INCT-MPH-2). (author)

  5. BIOACTIVE COMPOUNDS IN CONVENTIONAL AND NO ADDED SUGARS RED STRAWBERRY GUAVA (Psidium cattleianum Sabine JELLIES

    Directory of Open Access Journals (Sweden)

    GABRIELA NIEMEYER REISSIG

    Full Text Available ABSTRACT This study aimed to prepare jellies of conventional type of red strawberry guava (with added sucrose and no added sugar and evaluate the physical and chemical composition and content of bioactive compounds in them. Four jellies formulations were prepared: conventional with addition of sucrose (F1, aspartame (F2, saccharin and cyclamate (F3, acesulfame and sucralose (F4. Physicochemical analysis of pH were carried out, as well as analysis of titratable acidity, total soluble solids, ashes, proteins, lipids, moisture, carbohydrates, calories, lightness, color tone, total phenols, anthocyanins, carotenoids, ascorbic acid and antioxidant activity, by the capture of DPPH and ABTS radicals. Conventional and no added sugars jellies did not differ for total phenols, total anthocyanins and ascorbic acid. However, processing exerted significant influence (p=0.05 on total carotenoids and antioxidant activity. It is feasible to use red strawberry guava for the preparation of conventional and no added sugar jellies. The products, however, show a significant difference in carotenoids content, with the highest content of these and higher antioxidant activity in processed jellies without sugars addition.

  6. Low-/No-Calorie Sweeteners: A Review of Global Intakes

    Directory of Open Access Journals (Sweden)

    Danika Martyn

    2018-03-01

    Full Text Available The current review examined published data on the intake of all major low-/no-calorie sweeteners—aspartame, acesulfame-K, saccharin, sucralose, cyclamate, thaumatin and steviol glycosides—globally over the last decade. The most detailed and complex exposure assessments were conducted in Europe, following a standardized approach. Japan and Korea similarly had up-to-date and regular intake data available. The data for other Asian countries, Latin America, Australia/New Zealand and global estimates, evaluated by the Joint FAO/WHO Expert Committee on Food Additives (JECFA, while available, were shown to be more limited in terms of design. Overall, the studies conducted since 2008 raised no concerns with respect to exceedance of individual sweetener acceptable daily intake (ADIs among the general population globally. The data identified do not suggest a shift in exposure over time, with several studies indicating a reduction in intake. However, some data suggest there may have been an increase in the numbers of consumers of low-/no-calorie-sweetened products. Future research should consider a more standardized approach to allow the monitoring of potential changes in exposure based upon events such as sugar reduction recommendations, to ensure there is no shift in intake, particularly for high-risk individuals, including diabetics and children with specific dietary requirements, and to ensure risk management decisions are based on quality intake analyses.

  7. Contaminants of emerging concern in surface waters in Barbados, West Indies.

    Science.gov (United States)

    Edwards, Quincy A; Kulikov, Sergei M; Garner-O'Neale, Leah D; Metcalfe, Chris D; Sultana, Tamanna

    2017-11-14

    Contaminants of emerging concern (CECs), including pharmaceuticals, artificial sweeteners, steroid hormones, and current-use pesticides have been detected in surface waters around the world, but to date, there have been no reports in the peer-reviewed literature on the levels of these classes of contaminants in freshwater resources in the Caribbean region. In the present study, multi-residue solid phase extraction (SPE) and liquid chromatography with tandem mass spectroscopy (LC-MS/MS) were used to analyze grab samples of surface waters collected from five different watersheds in Barbados, West Indies. The artificial sweeteners (AS), acesulfame, cyclamate, saccharin, and sucralose were widely detected in the watersheds, indicating contamination from domestic wastewater, and the concentrations of these chemical tracers in water were correlated with the concentrations of the non-prescription pharmaceutical, ibuprofen (R 2 values of 0.4-0.6). Surprisingly, the concentrations of another chemical tracer of domestic wastewater, caffeine were not correlated with ibuprofen or AS concentrations. Several other prescription pharmaceuticals and the steroid hormones, estrone and androstenedione, were detected in selected watersheds at low ng/L concentrations. The fungicide, chlorothalonil was widely detected in surface waters at low (contamination of water resources by pharmaceuticals.

  8. Analysis of a variety of inorganic and organic additives in food products by ion-pairing liquid chromatography coupled to high-resolution mass spectrometry.

    Science.gov (United States)

    Kaufmann, Anton; Widmer, Mirjam; Maden, Kathryn; Butcher, Patrick; Walker, Stephan

    2018-03-05

    A reversed-phase ion-pairing chromatographic method was developed for the detection and quantification of inorganic and organic anionic food additives. A single-stage high-resolution mass spectrometer (orbitrap ion trap, Orbitrap) was used to detect the accurate masses of the unfragmented analyte ions. The developed ion-pairing chromatography method was based on a dibutylamine/hexafluoro-2-propanol buffer. Dibutylamine can be charged to serve as a chromatographic ion-pairing agent. This ensures sufficient retention of inorganic and organic anions. Yet, unlike quaternary amines, it can be de-charged in the electrospray to prevent the formation of neutral analyte ion-pairing agent adducts. This process is significantly facilitated by the added hexafluoro-2-propanol. This approach permits the sensitive detection and quantification of additives like nitrate and mono-, di-, and triphosphate as well as citric acid, a number of artificial sweeteners like cyclamate and aspartame, flavor enhancers like glutamate, and preservatives like sorbic acid. This is a major advantage, since the currently used analytical methods as utilized in food safety laboratories are only capable in monitoring a few compounds or a particular category of food additives. Graphical abstract Deptotonation of ion pair agent in the electrospray interface.

  9. Metabolic acidosis mimicking diabetic ketoacidosis after use of calorie-free mineral water.

    Science.gov (United States)

    Dahl, Gry T; Woldseth, Berit; Lindemann, Rolf

    2012-09-01

    A previously healthy boy was admitted with fever, tachycardia, dyspnea, and was vomiting. A blood test showed a severe metabolic acidosis with pH 7.08 and an anion gap of 36 mmol/L. His urine had an odor of acetone. The serum glucose was 5.6 mmol/L, and no glucosuria was found. Diabetic ketoacidosis could therefore be eliminated. Lactate level was normal. Tests for the most common metabolic diseases were negative. Because of herpes stomatitis, the boy had lost appetite and only been drinking Diet Coke and water the last days. Diet Coke or Coca-Cola Light is sweetened with a blend containing cyclamates, aspartame, and acesulfame potassium, all free of calories. The etiology of the metabolic acidosis appeared to be a catabolic situation exaggerated by fasting with no intake of calories. The elevated anion gap was due to a severe starvation ketoacidosis, mimicking a diabetic ketoacidosis. Pediatricians should recommend carbohydrate/calorie-containing fluids for rehydration of children with acute fever, diarrhea, or illness.

  10. Probabilistic modelling of human exposure to intense sweeteners in Italian teenagers: validation and sensitivity analysis of a probabilistic model including indicators of market share and brand loyalty.

    Science.gov (United States)

    Arcella, D; Soggiu, M E; Leclercq, C

    2003-10-01

    For the assessment of exposure to food-borne chemicals, the most commonly used methods in the European Union follow a deterministic approach based on conservative assumptions. Over the past few years, to get a more realistic view of exposure to food chemicals, risk managers are getting more interested in the probabilistic approach. Within the EU-funded 'Monte Carlo' project, a stochastic model of exposure to chemical substances from the diet and a computer software program were developed. The aim of this paper was to validate the model with respect to the intake of saccharin from table-top sweeteners and cyclamate from soft drinks by Italian teenagers with the use of the software and to evaluate the impact of the inclusion/exclusion of indicators on market share and brand loyalty through a sensitivity analysis. Data on food consumption and the concentration of sweeteners were collected. A food frequency questionnaire aimed at identifying females who were high consumers of sugar-free soft drinks and/or of table top sweeteners was filled in by 3982 teenagers living in the District of Rome. Moreover, 362 subjects participated in a detailed food survey by recording, at brand level, all foods and beverages ingested over 12 days. Producers were asked to provide the intense sweeteners' concentration of sugar-free products. Results showed that consumer behaviour with respect to brands has an impact on exposure assessments. Only probabilistic models that took into account indicators of market share and brand loyalty met the validation criteria.

  11. The role of artificial and natural sweeteners in reducing the consumption of table sugar: A narrative review.

    Science.gov (United States)

    Mooradian, Arshag D; Smith, Meridith; Tokuda, Masaaki

    2017-04-01

    The rapid increase in the prevalence of obesity worldwide has been partially attributed to the overconsumption of added sugars. Recent guidelines call for limiting the consumption of simple sugars to less than 10% of daily caloric consumption. High intensity sweeteners are regulated as food additives and include aspartame, acesulfame-k, neotame, saccharin, sucralose, cyclamate and alitame. Steviol glycosides and Luo Han Guo fruit extracts are high intensity sweeteners that are designated as generally recognized as safe (GRAS). Commonly used non-caloric artificial sweeteners may have unfavorable effect on health including glucose intolerance and failure to cause weight reduction. The nutritive sweeteners include sugar alcohols such as sorbitol, xylitol, lactitol, mannitol, erythritol, trehalose and maltitol. Naturally occurring rare sugars have recently emerged as an alternative category of sweeteners. These monosaccharides and their derivatives are found in nature in small quantities and lack significant calories. This category includes d-allulose (d-psicose), d-tagatose, d-sorbose and d-allose. Limiting consumption of any sweetener may well be the best health advice. Identifying natural sweeteners that have favorable effects on body weight and metabolism may help achieving the current recommendations of restricting simple sugar consumption. Copyright © 2017 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

  12. Determination of essential elements in dietetic sample by neutron activation analysis

    International Nuclear Information System (INIS)

    Siquelli, Murilo V.; Maihara, Vera A. Maihara

    2005-01-01

    In the last years there has been an increase of the dietetic product consumption by people who suffer from diabetes, heart disease and by people concerned about having a healthy life as well. Despite the increase of dietetic product presents in the diet of the Brazilian population, the use of these products is still controversial. The analysis of the nutritional composition of these products is becoming important because a great number of people is changing their traditional food by dietetic products. In the literature, there is no information about the inorganic composition, mainly related to the essential elements, in the dietetic products: diet and light . In this study are presented preliminary results of the concentrations of Br, Ca, Cr, Fe, Na and Zn determined by Instrumental Neutron Activation Analysis in aspartame, saccharin and cyclamate sodium , and stevia based sweetener samples. Gelatin samples, diet and light, were also analyzed. Methodology validation was done analyzing NIST reference materials Tea Leaves (INCT-TL-1) and Mixed Polish Herbs (INCT-MPH-2). (author)

  13. Development of pitanga nectar with different sweeteners by sensory analysis: ideal pulp dilution, ideal sweetness, and sweetness equivalence

    Directory of Open Access Journals (Sweden)

    Mírian Luisa Faria Freitas

    2014-03-01

    Full Text Available The objective of this study was to develop pitanga nectar formulations in which sucrose was replaced with different sweeteners. Consumer tests were conducted with 50 fruit juice consumers, and a just-about-right scale was used to determine the ideal pulp dilution and ideal sweetness with sucrose. Furthermore, the adequate concentrations of six sweeteners were determined to obtain the equivalent sweetness of sucrose using relative to these concentrations the magnitude estimation model with 19 selected assessors. The ideal dilution test resulted in 25% pulp, and the ideal sweetness test, 10% sucrose. Sweetener concentrations to replace sucrose were 0.0160%, 0.0541%, 0.1000%, 0.0999%, 0.0017%, and 0.0360%, respectively, for sucralose, aspartame, stevia 40% rebaudioside A, stevia 95% rebaudioside A, neotame, and a 2:1 cyclamate/saccharin blend. These results can be used to prepare pitanga nectar with different sweeteners and obtain the same sweetness intensity in less caloric products than that of nectar prepared with sucrose.

  14. Stevia and Saccharin Preferences in Rats and Mice

    Science.gov (United States)

    Bahrani, Mahsa; Zukerman, Steven; Ackroff, Karen

    2010-01-01

    Use of natural noncaloric sweeteners in commercial foods and beverages has expanded recently to include compounds from the plant Stevia rebaudiana. Little is known about the responses of rodents, the animal models for many studies of taste systems and food intake, to stevia sweeteners. In the present experiments, preferences of female Sprague–Dawley rats and C57BL/6J mice for different stevia products were compared with those for the artificial sweetener saccharin. The stevia component rebaudioside A has the most sweetness and least off-tastes to human raters. In ascending concentration tests (48-h sweetener vs. water), rats and mice preferred a high-rebaudioside, low-stevioside extract as strongly as saccharin, but the extract stimulated less overdrinking and was much less preferred to saccharin in direct choice tests. Relative to the extract, mice drank more pure rebaudioside A and showed stronger preferences but still less than those for saccharin. Mice also preferred a commercial mixture of rebaudioside A and erythritol (Truvia). Similar tests of sweet receptor T1R3 knockout mice and brief-access licking tests with normal mice suggested that the preferences were based on sweet taste rather than post-oral effects. The preference response of rodents to stevia sweeteners is notable in view of their minimal response to some other noncaloric sweeteners (aspartame and cyclamate). PMID:20413452

  15. Application of dispersive solid-phase extraction and ultra-fast liquid chromatography-tandem quadrupole mass spectrometry in food additive residue analysis of red wine.

    Science.gov (United States)

    Chen, Xiao-Hong; Zhao, Yong-Gang; Shen, Hao-Yu; Jin, Mi-Cong

    2012-11-09

    A novel and effective dispersive solid-phase extraction (dSPE) procedure with rapid magnetic separation using ethylenediamine-functionalized magnetic polymer as an adsorbent was developed. The new procedure had excellent clean-up ability for the selective removal of the matrix in red wine. An accurate, simple, and rapid analytical method using ultra-fast liquid chromatography-tandem quadrupole mass spectrometry (UFLC-MS/MS) for the simultaneous determination of nine food additives (i.e., acesulfame, saccharin, sodium cyclamate, aspartame, benzoic acid, sorbic acid, stevioside, dehydroacetic acid, and neotame) in red wine was also used and validated. Recoveries ranging from 78.5% to 99.2% with relative standard deviations ranging from 0.46% to 6.3% were obtained using the new method. All target compounds showed good linearities in the tested range with correlation coefficients (r) higher than 0.9993. The limits of quantification for the nine food additives were between 0.10 μg/L and 50.0 μg/L. The proposed dSPE-UFLC-MS/MS method was successfully applied in the food-safety risk monitoring of real red wine in Zhejiang Province, China. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  16. Artificial sweeteners as potential tracers of municipal landfill leachate

    International Nuclear Information System (INIS)

    Roy, James W.; Van Stempvoort, Dale R.; Bickerton, Greg

    2014-01-01

    Artificial sweeteners are gaining acceptance as tracers of human wastewater in the environment. The 3 artificial sweeteners analyzed in this study were detected in leachate or leachate-impacted groundwater at levels comparable to those of untreated wastewater at 14 of 15 municipal landfill sites tested, including several closed for >50 years. Saccharin was the dominant sweetener in old (pre-1990) landfills, while newer landfills were dominated by saccharin and acesulfame (introduced 2 decades ago; dominant in wastewater). Cyclamate was also detected, but less frequently. A case study at one site illustrates the use of artificial sweeteners to identify a landfill-impacted groundwater plume discharging to a stream. The study results suggest that artificial sweeteners can be useful tracers for current and legacy landfill contamination, with relative abundances of the sweeteners potentially providing diagnostic ability to distinguish different landfills or landfill cells, including crude age-dating, and to distinguish landfill and wastewater sources. -- Highlights: • Artificial sweeteners detected at 14 of 15 municipal landfill sites. • Concentrations comparable to wastewater even at sites closed for >50 yr. • Saccharin elevated at all sites; potentially diagnostic of landfill impacts. • Potential for age-dating recent (past 2 decades) waste with acesulfame. -- Artificial sweeteners may be useful for tracing landfill leachate contamination and distinguishing it from wastewater impacts

  17. Quantification of four artificial sweeteners in Finnish surface waters with isotope-dilution mass spectrometry

    International Nuclear Information System (INIS)

    Perkola, Noora; Sainio, Pirjo

    2014-01-01

    The artificial sweeteners sucralose (SCL), acesulfame (ACS), saccharin (SAC), and cyclamate (CYC) have been detected in environmental waters in Europe and North America. Higher environmental levels are expected in view of the increasing consumption of these food additives. In this study, an isotope-dilution mass spectrometry (IDMS) LC–MS/MS method was developed and validated for quantifying the four artificial sweeteners in boreal lakes (n = 3) and rivers (n = 12). The highest concentrations of ACS, SAC, CYC and SCL were 9,600, 490, 210 and 1000 ng/L, respectively. ACS and SAC were detected in all studied samples, and CYC and SCL in 98% and 56% of the samples. Seasonal trends of ACS and SAC were observed in some rivers. ACS and SCL concentrations in rivers correlated linearly with population equivalents of the wastewater treatment plants in the catchment areas, whereas SAC and CYC concentrations depend more on the source. -- Highlights: • A reliable method for analysing artificial sweeteners in water was validated. • Artificial sweeteners were quantified in boreal rivers and lakes. • Most concentrations were in accordance with previous European studies. • Acesulfame and saccharine concentrations were high in the most contaminated rivers. • Correlation observed between concentrations and mean water throughflow in rivers. -- High concentrations of artificial sweeteners were obtained, which indicates slow or negligible degradation of these compounds in boreal surface waters

  18. Lipid-Lowering Pharmaceutical Clofibrate Inhibits Human Sweet Taste

    Science.gov (United States)

    Kochem, Matthew

    2017-01-01

    T1R2-T1R3 is a heteromeric receptor that binds sugars, high potency sweeteners, and sweet taste blockers. In rodents, T1R2-T1R3 is largely responsible for transducing sweet taste perception. T1R2-T1R3 is also expressed in non-taste tissues, and a growing body of evidence suggests that it helps regulate glucose and lipid metabolism. It was previously shown that clofibric acid, a blood lipid-lowering drug, binds T1R2-T1R3 and inhibits its activity in vitro. The purpose of this study was to determine whether clofibric acid inhibits sweetness perception in humans and is, therefore, a T1R2-T1R3 antagonist in vivo. Fourteen participants rated the sweetness intensity of 4 sweeteners (sucrose, sucralose, Na cyclamate, acesulfame K) across a broad range of concentrations. Each sweetener was prepared in solution neat and in mixture with either clofibric acid or lactisole. Clofibric acid inhibited sweetness of every sweetener. Consistent with competitive binding, inhibition by clofibric acid was diminished with increasing sweetener concentration. This study provides in vivo evidence that the lipid-lowering drug clofibric acid inhibits sweetness perception and is, therefore, a T1R carbohydrate receptor inhibitor. Our results are consistent with previous in vitro findings. Given that T1R2-T1R3 may in part regulate glucose and lipid metabolism, future studies should investigate the metabolic effects of T1R inhibition. PMID:27742692

  19. Hypercrosslinked particles for the extraction of sweeteners using dispersive solid-phase extraction from environmental samples.

    Science.gov (United States)

    Lakade, Sameer S; Zhou, Qing; Li, Aimin; Borrull, Francesc; Fontanals, Núria; Marcé, Rosa M

    2018-04-01

    This work presents a new extraction material, namely, Q-100, based on hypercrosslinked magnetic particles, which was tested in dispersive solid-phase extraction for a group of sweeteners from environmental samples. The hypercrosslinked Q-100 magnetic particles had the advantage of suitable pore size distribution and high surface area, and showed good retention behavior toward sweeteners. Different dispersive solid-phase extraction parameters such as amount of magnetic particles or extraction time were optimized. Under optimum conditions, Q-100 showed suitable apparent recovery, ranging in the case of river water sample from 21 to 88% for all the sweeteners, except for alitame (12%). The validated method based on dispersive solid-phase extraction using Q-100 followed by liquid chromatography with tandem mass spectrometry provided good linearity and limits of quantification between 0.01 and 0.1 μg/L. The method was applied to analyze samples from river water and effluent wastewater, and four sweeteners (acesulfame, saccharin, cyclamate, and sucralose) were found in both types of sample. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Suitability of pharmaceuticals and personal care products (PPCPs) and artificial sweeteners (ASs) as wastewater indicators in the Pearl River Delta, South China.

    Science.gov (United States)

    Yang, Yuan-Yuan; Liu, Wang-Rong; Liu, You-Sheng; Zhao, Jian-Liang; Zhang, Qian-Qian; Zhang, Min; Zhang, Jin-Na; Jiang, Yu-Xia; Zhang, Li-Juan; Ying, Guang-Guo

    2017-07-15

    Wastewater indicator is a useful tool for evaluating the wastewater impact on natural water, but there is little information about the suitability of wastewater indicators for different regions. This study aimed to select suitable wastewater indicators in the Pearl River Delta region, south China by screening a range of wastewater related organic compounds. The screening campaign was carried out by investigating the occurrence and removal efficiencies of 93 pharmaceuticals and personal care products (PPCPs) and 5 artificial sweeteners (ASs) in nine wastewater treatment plants (WWTPs) located in the region, and the occurrence of these target compounds in the contaminated and clean surface water of the Pearl River. An ideal wastewater indicator should be hydrophilic, source-specific for domestic wastewater, ubiquitous in contaminated surface water with detection frequency (DF) >80% and absent in background water samples. For liable indicators, high removal rates (>90%) should be observed in WWTPs and they should be detected in all the influent samples at concentrations fifty times higher than their limits of quantification. For conservative indicators, low removal rates (<50%) should be observed in WWTPs and they should be detected in all the effluent samples at concentrations fifty times higher than their limits of quantification. Based on the above criteria, sucralose and fluconazole were selected as conservative indicators in the region, while cyclamate, saccharin, methyl paraben, ethyl paraben, propyl paraben, paracetamol, salicylic acid and caffeine were selected as liable indicators. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Fate of artificial sweeteners through wastewater treatment plants and water treatment processes

    Science.gov (United States)

    Li, Shaoli; Ren, Yuhang; Fu, Yingying; Gao, Xingsheng; Jiang, Cong; Wu, Gang; Ren, Hongqiang

    2018-01-01

    Five full-scale wastewater treatment plants (WWTPs) in China using typical biodegradation processes (SBR, oxidation ditch, A2/O) were selected to assess the removal of four popular artificial sweeteners (ASs). All four ASs (acesulfame (ACE), sucralose (SUC), cyclamate (CYC) and saccharin (SAC)) were detected, ranging from 0.43 to 27.34μg/L in the influent. Higher concentrations of ASs were measured in winter. ACE could be partly removed by 7.11–50.76% through biodegradation and especially through the denitrifying process. The A2/O process was the most efficient at biodegrading ASs. Adsorption (by granular activated carbon (GAC) and magnetic resin) and ultraviolet radiation-based advanced oxidation processes (UV/AOPs) were evaluated to remove ASs in laboratory-scale tests. The amounts of resin adsorbed were 3.33–18.51 times more than those of GAC except for SUC. The adsorption ability of resin decreased in the order of SAC > ACE > CYC > SUC in accordance with the pKa. Degradation of ASs followed pseudo-first-order kinetics in UV/H2O2 and UV/PDS. When applied to the secondary effluent, ASs could be degraded from 30.87 to 99.93% using UV/PDS in 30 minutes and UV/PDS was more efficient and economic. PMID:29293534

  2. Discrimination of sweeteners based on the refractometric analysis

    International Nuclear Information System (INIS)

    Bodurov, I; Viraneva, A; Yovcheva, T; Vlaeva, I

    2017-01-01

    In the present work, the refractive characteristics of aqueous solutions of several sweeteners are investigated. These data in combination with ones from other sensors should find application for brief determination of sweeteners content in food and dynamic monitoring of food quality. The refractive indices of pure (distilled) water and aqueous solutions of several commonly used natural and artificial sweeteners (glucose, fructose, sucrose, lactose, sorbitol [E420], isomalt [E953], saccharin sodium [E950], cyclamate sodium and glycerol [E422]) with 10 wt.% concentration are accurately measured at 405 nm, 532 nm and 632.8 nm wavelengths. The measurements are carried out using three wavelength laser microrefractometer based on the total internal reflection method. The critical angle is determined by the disappearance of the diffraction orders from a metal grating. The experimental uncertainty is less than ±0.0001. The dispersion dependences of the refractive indices are obtained using the one-term Sellmeier model. Based on the obtained experimental data additional refractive and dispersion characteristics are calculated. (paper)

  3. Noncaloric Sweeteners in Children: A Controversial Theme

    Directory of Open Access Journals (Sweden)

    Samuel Durán Agüero

    2018-01-01

    Full Text Available Noncaloric sweeteners (NCS are food additives used to provide sweetness without adding calories. Their consumption has become more widespread around the world in all age groups, including children. The aim of this study is to show the state of the art about the intake of noncaloric sweeteners in children, as well as their benefits and consumption risk. Scientific searchers were used (PUBMED, Scopus, and Scielo to analyze articles that included keywords (noncaloric sweeteners/saccharin/cyclamate/acesulfame potassium/aspartame/sucralose/stevia/children in English, Spanish, and Portuguese. Authors conclude that it is imperative that health professionals judiciously and individually evaluate the overall benefits and risks of NCS use in consumers before recommending their use. Different subgroups of the population incorporate products containing NCS in their diet with different objectives, which should be considered when recommending a diet plan for the consumer. In childhood, in earlier age groups, this type of additives should be used as a dietary alternative when other forms of prevention in obesity are not sufficient.

  4. Fate of artificial sweeteners through wastewater treatment plants and water treatment processes.

    Science.gov (United States)

    Li, Shaoli; Ren, Yuhang; Fu, Yingying; Gao, Xingsheng; Jiang, Cong; Wu, Gang; Ren, Hongqiang; Geng, Jinju

    2018-01-01

    Five full-scale wastewater treatment plants (WWTPs) in China using typical biodegradation processes (SBR, oxidation ditch, A2/O) were selected to assess the removal of four popular artificial sweeteners (ASs). All four ASs (acesulfame (ACE), sucralose (SUC), cyclamate (CYC) and saccharin (SAC)) were detected, ranging from 0.43 to 27.34μg/L in the influent. Higher concentrations of ASs were measured in winter. ACE could be partly removed by 7.11-50.76% through biodegradation and especially through the denitrifying process. The A2/O process was the most efficient at biodegrading ASs. Adsorption (by granular activated carbon (GAC) and magnetic resin) and ultraviolet radiation-based advanced oxidation processes (UV/AOPs) were evaluated to remove ASs in laboratory-scale tests. The amounts of resin adsorbed were 3.33-18.51 times more than those of GAC except for SUC. The adsorption ability of resin decreased in the order of SAC > ACE > CYC > SUC in accordance with the pKa. Degradation of ASs followed pseudo-first-order kinetics in UV/H2O2 and UV/PDS. When applied to the secondary effluent, ASs could be degraded from 30.87 to 99.93% using UV/PDS in 30 minutes and UV/PDS was more efficient and economic.

  5. Inhibition of human immunodeficiency virus replication by a dual CCR5/CXCR4 antagonist

    DEFF Research Database (Denmark)

    Princen, Katrien; Hatse, Sigrid; Vermeire, Kurt

    2004-01-01

    Here we report that the N-pyridinylmethyl cyclam analog AMD3451 has antiviral activity against a wide variety of R5, R5/X4, and X4 strains of human immunodeficiency virus type 1 (HIV-1) and HIV-2 (50% inhibitory concentration [IC(50)] ranging from 1.2 to 26.5 microM) in various T-cell lines, CCR5...... at the virus entry stage. AMD3451 dose-dependently inhibited the intracellular Ca(2+) signaling induced by the CXCR4 ligand CXCL12 in T-lymphocytic cells and in CXCR4-transfected cells, as well as the Ca(2+) flux induced by the CCR5 ligands CCL5, CCL3, and CCL4 in CCR5-transfected cells. The compound did...... not interfere with chemokine-induced Ca(2+) signaling through CCR1, CCR2, CCR3, CCR4, CCR6, CCR9, or CXCR3 and did not induce intracellular Ca(2+) signaling by itself at concentrations up to 400 microM. In freshly isolated monocytes, AMD3451 inhibited the Ca(2+) flux induced by CXCL12 and CCL4...

  6. Potency of Purple Sweet Potato’s Anthocyanin as Biosensor for Detection of Chemicals in Food Products

    Science.gov (United States)

    Wulandari, A.; Sunarti, TC; Fahma, F.; Noor, E.

    2018-05-01

    Bioactive compounds such as anthocyanin are a natural ingredient that produces color with typical specificity. Anthocyanin from Ayamurasaki purple sweet potato (Ipomoea batatas L.) was extracted in ethanol and used as crude anthocyanin extracts. The color of bioactive anthocyanin can be used as a biosensor to detect chemical of food products because it provides a unique color change. However, the each bioactive has a particular sensitivity and selectivity to a specific chemical, so it is necessary to select and test the selectivity. Six chemicals, which were sodium nitrite, sodium benzoate, sodium cyclamate (food additives), formalin, borax (illegal food preservatives), and residue fertilizer (urea) were tested and observed for its color change. The results showed that the bioactive anthocyanin of purple sweet potato with the concentration of ± 42.65 ppm had better selectivity and sensitivity to sodium nitrite with a detection limit of 100 ppm, where the color change response time ranged from 15-20 minutes. The selectivity and sensitivity of this bioactive can be used as the basic information for the development of biosensor.

  7. Multicomponent analysis of fat- and water-soluble vitamins and auxiliary substances in multivitamin preparations by qNMR.

    Science.gov (United States)

    Eiff, Julia; Monakhova, Yulia B; Diehl, Bernd W K

    2015-04-01

    A nuclear magnetic resonance (NMR) spectroscopic method was tested to control 12 vitamins and accompanying substances in multivitamin preparations. The limits of detection (LODs) and limits of quantification (LOQs) varied in the 9.0-77.0 mg/kg and in the 34.5-93.5 mg/kg range, respectively. The coefficients of variation (CVs) ranged between 0.9% and 12%. The (1)H NMR spectra showed linearity for the 140-260 mg sample weight (R(2) > 0.918). The NMR spectra of multivitamin preparations showed the presence of different degradation products of ascorbic acid. The NMR method was applied to 13 different multivitamin preparations including tablets, capsules, and effervescent tablets with average recovery rates between 85% and 132%. A number of accompanying substances (citric acid, mannitol, saccharin, cyclamate, sum of steviol glycosides, and butylhydroxytoluene) were additionally identified and quantified. NMR was found to be suitable for the simultaneous qualitative measurement of water- and fat-soluble vitamins and accompanying substances and shows some promise for quantitative determination of at least 5 vitamins (B1, B3, B5, B6, and E) in multivitamin preparations.

  8. Adsorptive Removal of Artificial Sweeteners from Water Using Metal-Organic Frameworks Functionalized with Urea or Melamine.

    Science.gov (United States)

    Seo, Pill Won; Khan, Nazmul Abedin; Hasan, Zubair; Jhung, Sung Hwa

    2016-11-02

    A highly porous metal-organic framework (MOF), MIL-101, was modified to introduce urea or melamine via grafting on open metal sites of the MOF. Adsorptive removal of three artificial sweeteners (ASWs) was studied using the MOFs, with or without modifications (including nitration), and activated carbon (AC). The adsorbed quantities (based on the weight of the adsorbent) of saccharin (SAC) under various conditions decreased in the order urea-MIL-101 > melamine-MIL-101 > MIL-101 > AC > O 2 N-MIL-101; however, the quantities based on unit surface area are in the order melamine-MIL-101 > urea-MIL-101 > MIL-101 > O 2 N-MIL-101. Similar ASWs [acesulfame (ACE) and cyclamate (CYC)] showed the same tendency. The mechanism for very favorable adsorption of SAC, ACE, and CYC over urea- and melamine-MIL-101 could be explained by H-bonding on the basis of the contents of -NH 2 groups on the MOFs and the adsorption results under a wide range of pH values. Moreover, the direction of H-bonding could be clearly defined (H acceptor: ASWs; H donor: MOFs). Urea-MIL-101 and melamine-MIL-101 could be suggested as competitive adsorbents for organic contaminants (such as ASWs) with electronegative atoms, considering their high adsorption capacity (for example, urea-MIL-101 had 2.3 times the SAC adsorption of AC) and ready regeneration.

  9. Distribution of artificial sweeteners in dust and soil in China and their seasonal variations in the environment of Tianjin.

    Science.gov (United States)

    Gan, Zhiwei; Sun, Hongwen; Yao, Yiming; Zhao, Yangyang; Li, Yan; Zhang, Yanwei; Hu, Hongwei; Wang, Ruonan

    2014-08-01

    A nationwide investigation on the occurrence of artificial sweeteners (ASs) was conducted by collecting 98 paired outdoor dust and soil samples from mainland China. The ASs were widely detected in Chinese atmospheric dry deposition and soil samples, at concentrations up to 6450 and 1280 ng/g, respectively. To give a picture on AS distribution and source in the whole environment, the concentrations and seasonal variations of ASs in Tianjin were studied, including atmosphere, soil, and water samples. The AS levels were significantly higher in Haihe river at TJW (a sampling site in central city) in winter, while no obviously seasonal trends were obtained at BYL (close to a AS factory) and the site at a wastewater treatment plant. Saccharin, cyclamate, and acesulfame were the dominant ASs in both gas and particulate phase, with concentrations varying from 0.02 to 1940 pg/m(3). Generally, gas phase concentrations of the ASs were relatively higher in summer, while opposite results were acquired for particulate phase. Wet and dry deposition fluxes were calculated based on the measured AS levels. The results indicated that both wet and dry deposition could efficiently remove ASs in the atmosphere and act as important pollutant sources for the ASs in surface environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Water-activity of dehydrated guava slices sweeteners

    International Nuclear Information System (INIS)

    Ayub, M.; Zeb, A.; Ullah, J.

    2005-01-01

    A study was carried out to investigate the individual and combined effect of caloric sweeteners (sucrose, glucose and fructose) and non-caloric sweeteners (saccharine, cyclamate and aspartame) along with antioxidants (citric acid and ascorbic acid) and chemical preservatives (potassium metabisulphite and potassium sorbate) on the water-activity (a/sub w/) of dehydrated guava slices. Different dilutions of caloric sweeteners (20, 30, 40 and 50 degree brix (bx) and non-caloric sweeteners (equivalent to sucrose sweetness) were used. Guava slices were osmotically dehydrated in these solutions and then dehydrated initially at 0 and then at 60 degree C to final moisture-content of 20-25%. Guava slices prepared with sucrose: glucose 7:3 potassium metabisulphite, ascorbic acid and citric acid produced best quality products, which have minimum (a/sub w/) and best overall sensory characteristics. The analysis showed that treatments and their various concentrations had a significant effect (p=0.05) on (a/sub w/) of dehydrated guava slices. (author)

  11. Fate of artificial sweeteners through wastewater treatment plants and water treatment processes.

    Directory of Open Access Journals (Sweden)

    Shaoli Li

    Full Text Available Five full-scale wastewater treatment plants (WWTPs in China using typical biodegradation processes (SBR, oxidation ditch, A2/O were selected to assess the removal of four popular artificial sweeteners (ASs. All four ASs (acesulfame (ACE, sucralose (SUC, cyclamate (CYC and saccharin (SAC were detected, ranging from 0.43 to 27.34μg/L in the influent. Higher concentrations of ASs were measured in winter. ACE could be partly removed by 7.11-50.76% through biodegradation and especially through the denitrifying process. The A2/O process was the most efficient at biodegrading ASs. Adsorption (by granular activated carbon (GAC and magnetic resin and ultraviolet radiation-based advanced oxidation processes (UV/AOPs were evaluated to remove ASs in laboratory-scale tests. The amounts of resin adsorbed were 3.33-18.51 times more than those of GAC except for SUC. The adsorption ability of resin decreased in the order of SAC > ACE > CYC > SUC in accordance with the pKa. Degradation of ASs followed pseudo-first-order kinetics in UV/H2O2 and UV/PDS. When applied to the secondary effluent, ASs could be degraded from 30.87 to 99.93% using UV/PDS in 30 minutes and UV/PDS was more efficient and economic.

  12. Response of the grass-cutting ant Atta capiguara Gonçalves, 1944 (Hymenoptera: Formicidae to sugars and artificial sweeteners Resposta da saúva Atta capiguara Gonçalves, 1944 (Hymenoptera: Formicidae a açúcares e edulcorantes artificiais

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Castellani Boaretto

    2003-01-01

    Full Text Available Using of toxic baits made of dehydrated citric pulp to control grass-cutting ants can lead to unsatisfactory results because of the low attractiveness of the substrate to worker ants. This work aimed to identify attractive substances, with potential for incorporation in a matrix of granulated baits for grass-cutting ants, among several kinds of sugars and substances used in artificial sweeteners. Experiments were carried out in mature nests of Atta capiguara (Hym.: Formicidae set in pasture. Studied substances were sucrose, fructose, soluble starch, raffinose, maltose, lactose, sorbose, cellobiose, arabinose, xylose, glucose, galactose, rhamnose, arabinose, melezitose, saccharine and cyclamate (at 5.0% w/v. Later, on maltose, xylose, sucrose, fructose and glucose solutions were included at 5.0%, 7.5%, 10.0% and 20.0% w/v, respectively. Cellulose rectangles were used as vehicle and number of rectangles carried into the colonies was evaluated. Carrying rates were very low with maximum means of 9.6% for lactose and 6.0% for arabinose and cyclamate, at the 5.0% concentration. No differences (P > 0.05 were observed relatively to the control (distilled water. No effects were detected for solution, concentration and for the interaction of these factors. Sugars and artificial sweeteners studied were not attractive to Atta capiguara workers, turning their inclusion as attractants in toxic ant baits not viable.O uso de iscas tóxicas, formuladas à base de polpa cítrica desidratada, para o controle de formigas cortadeiras de gramíneas pode levar a resultados insatisfatórios devido à baixa atratividade do substrato às operárias. Este trabalho foi realizado com o objetivo de identificar substâncias atrativas e com potencial para incorporação em matrizes de iscas granuladas para formigas cortadeiras de gramíneas, dentre diversos tipos de açúcares e edulcorantes artificiais. Os experimentos foram realizados em ninhos adultos de Atta capiguara Gon

  13. O uso de adoçantes na gravidez: uma análise dos produtos disponíveis no Brasil The use of sweeteners in pregnancy: an analysis of products available in Brazil

    Directory of Open Access Journals (Sweden)

    Maria Regina Torloni

    2007-05-01

    Full Text Available Os adoçantes são freqüentemente utilizados por mulheres em idade reprodutiva. Esta é uma revisão narrativa da literatura a respeito dos adoçantes atualmente comercializados no mercado brasileiro. Existem poucas informações sobre o uso da sacarina e ciclamato na gestação, e seus efeitos sobre o feto. Devido às limitadas informações disponíveis e ao seu potencial carcinogênico em animais, a sacarina e o ciclamato devem ser evitados durante a gestação (risco C. O aspartame tem sido extensivamente estudado em animais, sendo considerado seguro para uso na gestação (risco B, exceto para mulheres homozigóticas para fenilcetonúria (risco C. A sucralose e o acessulfame-K não são tóxicos, carcinogênico ou mutagênicos em animais, mas não existem estudos controlados em humanos. Porém, como esses dois adoçantes não são metabolizados, parece improvável que seu uso durante a gestação possa ser prejudicial (risco B. A estévia, substância derivada de uma planta nativa brasileira, não produz efeitos adversos sobre a gestação em animais, porém não existem estudos em humanos (risco B. Os agentes de corpo usados na formulação dos adoçantes (manitol, sorbitol, xilitol, eritrol, lactilol, isomalte, maltilol, lactose, frutose, maltodextrina, dextrina e açúcar invertido são substâncias consideradas seguras para o consumo humano. Concluindo, segundo as evidências atualmente disponíveis, o aspartame, a sucralose, o acessulfame e a estévia podem ser utilizados com segurança durante a gestação.Sweeteners are frequently used by women of reproductive age. This is a narrative review about the sweeteners currently sold in the Brazilian commerce. There is a few information on the use of saccharin and cyclamates in pregnancy and their effects on the fetus. Due to the limited information available and their carcinogenic potential in animal species, saccharin and cyclamates should be avoided during pregnancy (risk C. Aspartame

  14. PENGGUNAAN PENGAWET DAN PEMANIS BUATAN PADA PANGAN JAJANAN ANAK SEKOLAH (PJAS DI WILAYAH KABUPATEN KULON PROGO-DIY (The Use of Preservatives and Artificial Sweeteners in Elementary School-Food in Kulon Progo District of DIY Province

    Directory of Open Access Journals (Sweden)

    Chatarina Wariyah

    2013-08-01

    Full Text Available School-food (SF is processed-foods sold by vendor in the elementary school. Recently, many SF has been found to contain excessive food additives and used hazardous substances those are prohibited i.e. formalin, boric acid and rhodamin. The prebious survey showed that the considerations for buying food of most people in Kulon Progo District of DIY province were price, taste, appearance, and were not of the quality and nutrition. The purpose of this research was to determine the SF profile in Kulon Progo District, especially those used excessive food additive (preservative and artificial sweetener, SF with hazardous substances, and the relation between SF condition and the education level of the vendor. The sampling method used Proportionate Random Sampling consists of two stages, namely: 1 sampling to determine the sub-district samples and 2 sampling to determine the amount of the elementary-school of each sub-district for SF sampling. The data were collected by direct observation, interview and experimental method. Analysis of sodium benzoat and sorbic acid, saccharin, sodium cyclamate, and unrecommended/hazardous substances were conducted in BBPOM Laboratory and BLK of Yoyakarta. The data were statistically analyzed by statistic-descriptive and processed with microsoft excell and SPSS for window version 13 for Spearman correlative test.The research showed that SF at the elementary school in Kulon Progo District indicated to contain excessive food additives and hazardous substances. There were 4% samples containing excessive sodium benzoat, sorbic acid and 8% samples containing excessive artificial sweetener of sodium cyclamate. SF with boric acid was 3% samples (cilok, sosis, kerupuk rambak and with formalin was 1% samples (burjo,cimol. There was a significant correlation between the education level of the SF vendor with knowledge about formalin, boric acid and artificial sweetener. Keywords: School-food, food-additives, unrecommended

  15. Evaluation of Brazilian light ketchups II: quantitative descriptive and physicochemical analysis Avaliação de catchups light do mercado brasileiro II: análise descritiva quantitativa e avaliação físico-química

    Directory of Open Access Journals (Sweden)

    Gisele Cristina Maziero de Campos Bannwart

    2008-03-01

    Full Text Available Samples of ketchup available on the Brazilian market, one traditional (sweetened with sucrose and three light versions (sweetened with aspartame, acesulfame-K and a blend of cyclamate, saccharin and stevia were evaluated for their physicochemical characteristics and sensory profile (Quantitative Descriptive Analysis. Four main groups of attributes were generated: appearance, oral texture, aroma and flavor. The samples presented significant differences in all attributes, except for syneresis and overripe tomato flavor. The highest means for sweetener and bitter tastes and aftertastes were observed for the samples sweetened with acesulfame-K and the blend of sweeteners. Although different characteristics were observed among the products evaluated and, despite the differences in the formulations, the light ketchup sweetened with aspartame was the one that presented properties most similar to those of the traditional ketchup.Amostras de catchup disponíveis no mercado brasileiro, uma tradicional (adoçada com sacarose e três light (adoçadas com aspartame, acessulfame-K e uma combinação de ciclamato, sacarina e estévia foram avaliadas quanto às características físico-químicas e ao perfil sensorial (Análise Descritiva Quantitativa. Quatro grandes grupos de atributos foram gerados: aparência, textura bucal, aroma e sabor. As amostras apresentaram diferença significativa em todos os atributos, exceto sinerese e tomate passado. As maiores médias para os atributos relacionados a sabor e sabor residual amargo e de adoçante foram obtidas para as amostras adoçadas com acessulfame-K e com a combinação de edulcorantes. Apesar das diferentes características observadas entre os produtos avaliados e das diferenças entre as formulações, o catchup light adoçado com aspartame foi o que apresentou propriedades mais próximas ao produto tradicional.

  16. High-performance ion mobility spectrometry with direct electrospray ionization (ESI-HPIMS) for the detection of additives and contaminants in food

    Energy Technology Data Exchange (ETDEWEB)

    Midey, Anthony J., E-mail: anthony.midey@excellims.com; Camacho, Amanda; Sampathkumaran, Jayanthi; Krueger, Clinton A.; Osgood, Mark A.; Wu, Ching

    2013-12-04

    Graphical abstract: -- Highlights: •A new ESI source was built for direct ionization from syringe. •Phthalates, food dyes, and sweeteners detected with high-performance IMS. •Phthalates directly detected in cola, soy bubble tea matrices with simple treatment. -- Abstract: High-performance ion mobility spectrometry (HPIMS) with an electrospray ionization (ESI) source detected a series of food contaminants and additive compounds identified as critical to monitoring the safety of food samples. These compounds included twelve phthalate plasticizers, legal and illegal food and cosmetic dyes, and artificial sweeteners that were all denoted as detection priorities. HPIMS separated and detected the range of compounds with a resolving power better than 60 in both positive and negative ion modes, comparable to the commonly used high-performance liquid chromatography (HPLC) methods, but with most acquisition times under a minute. The reduced mobilities, K{sub 0}, have been determined, as have the linear response ranges for ESI-HPIMS, which are 1.5–2 orders of magnitude for concentrations down to sub-ng μL{sup −1} levels. At least one unique mobility peak was seen for two subsets of the phthalates grouped by the country where they were banned. Furthermore, ESI-HPIMS successfully detected low nanogram levels of a phthalate at up to 30 times lower concentration than international detection levels in both a cola matrix and a soy-based bubble tea beverage using only a simplified sample treatment. A newly developed direct ESI source (Directspray) was combined with HPIMS to detect food-grade dyes and industrial dye adulterants, as well as the sweeteners sodium saccharin and sodium cyclamate, with the same good performance as with the phthalates. However, the Directspray method eliminated sources of carryover and decreased the time between sample runs. Limits-of-detection (LOD) for the analyte standards were estimated to be sub-ng μL{sup −1} levels without extensive

  17. Low Caloric Sweeteners for Diabetes and Obesity Care and Their

    Directory of Open Access Journals (Sweden)

    Mohammad Asif

    2015-10-01

    Full Text Available Diabetes and obesity are two common human disorders that affecting human health and invite various diseases and disorders in normal body functions. These diseases are very common worldwide. Diabetes occurs when high blood sugar levels develop. This happens when body can’t make and use all of the insulin it needs to blood sugar normally to keep blood sugar levels as normal as possible to control diabetes. Diabetic patients will need to follow a diet plan, do exercise and possibly take insulin injections. As part of eating plan, health care provider, and dietitian may ask to limit the amount of carbohydrates eat each day. Low-calorie sweeteners are one easy tool to help for follow eating plan. Obesity is more susceptible and often been associated with frequent ingestion of high energy food in high amount and high intake of sugars such as fermentable sugars such as sucrose, fructose, glucose, and maltose. Both diseases are may be genetically or due to hormonal imbalances. High energy sweeteners may causes caries in the teeth particularly susceptible to the children. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in obesity. Fortunately, low calorie artificial and natural alternatives of sugars have been developed as alternatives to fermentable sugars and have shown promise in these health issues. Although there are only few artificial sweeteners (saccharin, aspartame, acesulfam potassium, sucralose, cyclamate that have been approved as food additives by the Food and Drug Administration and additional other low-caloric sweeteners (sugar alcohols, neotame, stevia, erythritol, xylitol, tagatose that have FDA-generally recognized as safe. Given the health impact of sugars and other carbohydrates, professionals should be aware of the marketed available low caloric sweeteners and both their benefits and potential risks.

  18. How does tunneling contribute to counterintuitive H-abstraction reactivity of nonheme Fe(IV)O oxidants with alkanes?

    Science.gov (United States)

    Mandal, Debasish; Ramanan, Rajeev; Usharani, Dandamudi; Janardanan, Deepa; Wang, Binju; Shaik, Sason

    2015-01-21

    This article addresses the intriguing hydrogen-abstraction (H-abstraction) and oxygen-transfer (O-transfer) reactivity of a series of nonheme [Fe(IV)(O)(TMC)(Lax)](z+) complexes, with a tetramethyl cyclam ligand and a variable axial ligand (Lax), toward three substrates: 1,4-cyclohexadiene, 9,10-dihydroanthracene, and triphenyl phosphine. Experimentally, O-transfer-reactivity follows the relative electrophilicity of the complexes, whereas the corresponding H-abstraction-reactivity generally increases as the axial ligand becomes a better electron donor, hence exhibiting an antielectrophilic trend. Our theoretical results show that the antielectrophilic trend in H-abstraction is affected by tunneling contributions. Room-temperature tunneling increases with increase of the electron donation power of the axial-ligand, and this reverses the natural electrophilic trend, as revealed through calculations without tunneling, and leads to the observed antielectrophilic trend. By contrast, O-transfer-reactivity, not being subject to tunneling, retains an electrophilic-dependent reactivity trend, as revealed experimentally and computationally. Tunneling-corrected kinetic-isotope effect (KIE) calculations matched the experimental KIE values only if all of the H-abstraction reactions proceeded on the quintet state (S = 2) surface. As such, the present results corroborate the initially predicted two-state reactivity (TSR) scenario for these reactions. The increase of tunneling with the electron-releasing power of the axial ligand, and the reversal of the "natural" reactivity pattern, support the "tunneling control" hypothesis (Schreiner et al., ref 19). Should these predictions be corroborated, the entire field of C-H bond activation in bioinorganic chemistry would lay open to reinvestigation.

  19. Transport of sewage molecular markers through saturated soil column and effect of easily biodegradable primary substrate on their removal.

    Science.gov (United States)

    Foolad, Mahsa; Ong, Say Leong; Hu, Jiangyong

    2015-11-01

    Pharmaceutical and personal care products (PPCPs) and artificial sweeteners (ASs) are emerging organic contaminants (EOCs) in the aquatic environment. The presence of PPCPs and ASs in water bodies has an ecologic potential risk and health concern. Therefore, it is needed to detect the pollution sources by understanding the transport behavior of sewage molecular markers in a subsurface area. The aim of this study was to evaluate transport of nine selected molecular markers through saturated soil column experiments. The selected sewage molecular markers in this study were six PPCPs including acetaminophen (ACT), carbamazepine (CBZ), caffeine (CF), crotamiton (CTMT), diethyltoluamide (DEET), salicylic acid (SA) and three ASs including acesulfame (ACF), cyclamate (CYC), and saccharine (SAC). Results confirmed that ACF, CBZ, CTMT, CYC and SAC were suitable to be used as sewage molecular markers since they were almost stable against sorption and biodegradation process during soil column experiments. In contrast, transport of ACT, CF and DEET were limited by both sorption and biodegradation processes and 100% removal efficiency was achieved in the biotic column. Moreover, in this study the effect of different acetate concentration (0-100mg/L) as an easily biodegradable primary substrate on a removal of PPCPs and ASs was also studied. Results showed a negative correlation (r(2)>0.75) between the removal of some selected sewage chemical markers including ACF, CF, ACT, CYC, SAC and acetate concentration. CTMT also decreased with the addition of acetate, but increasing acetate concentration did not affect on its removal. CBZ and DEET removal were not dependent on the presence of acetate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. High-performance ion mobility spectrometry with direct electrospray ionization (ESI-HPIMS) for the detection of additives and contaminants in food

    International Nuclear Information System (INIS)

    Midey, Anthony J.; Camacho, Amanda; Sampathkumaran, Jayanthi; Krueger, Clinton A.; Osgood, Mark A.; Wu, Ching

    2013-01-01

    Graphical abstract: -- Highlights: •A new ESI source was built for direct ionization from syringe. •Phthalates, food dyes, and sweeteners detected with high-performance IMS. •Phthalates directly detected in cola, soy bubble tea matrices with simple treatment. -- Abstract: High-performance ion mobility spectrometry (HPIMS) with an electrospray ionization (ESI) source detected a series of food contaminants and additive compounds identified as critical to monitoring the safety of food samples. These compounds included twelve phthalate plasticizers, legal and illegal food and cosmetic dyes, and artificial sweeteners that were all denoted as detection priorities. HPIMS separated and detected the range of compounds with a resolving power better than 60 in both positive and negative ion modes, comparable to the commonly used high-performance liquid chromatography (HPLC) methods, but with most acquisition times under a minute. The reduced mobilities, K 0 , have been determined, as have the linear response ranges for ESI-HPIMS, which are 1.5–2 orders of magnitude for concentrations down to sub-ng μL −1 levels. At least one unique mobility peak was seen for two subsets of the phthalates grouped by the country where they were banned. Furthermore, ESI-HPIMS successfully detected low nanogram levels of a phthalate at up to 30 times lower concentration than international detection levels in both a cola matrix and a soy-based bubble tea beverage using only a simplified sample treatment. A newly developed direct ESI source (Directspray) was combined with HPIMS to detect food-grade dyes and industrial dye adulterants, as well as the sweeteners sodium saccharin and sodium cyclamate, with the same good performance as with the phthalates. However, the Directspray method eliminated sources of carryover and decreased the time between sample runs. Limits-of-detection (LOD) for the analyte standards were estimated to be sub-ng μL −1 levels without extensive sample handling

  1. Optimization of 64Cu production for Radio-metabolic therapy and for PET

    International Nuclear Information System (INIS)

    Groppi, F.; Bonardi, M.; Birattari, C.; Gini, L.; Guariglia, S.; Mainardi, C.; Menapace, E.

    2002-01-01

    The 6 4C u is a very interesting radioisotope for nuclear biomedical applications, due to its physical characteristics: a) it decay β+ and β- with maximum energy equal to 653 keV and 578 keV respectively, that correspond to maximum range of β+ in soft tissue ∼ 2.7 mm and average range ∼ 1 mm. In this way it is possible to give a local dose in the region of interest and to have a high resolution in the PET images; b) it has an half life of 12.7 h, that is suitable for medical applications, reducing the exposure of personnel and of the patients and the problem of waste discharge; c) besides the gamma of annihilation (36%), it has only one γ emission at 1345.84 keV (0.473%) with low intensity: this reduces the dose to healthy tissue and to medical personnel. For these reasons 6 4C u can be considered a dual purpose radionuclide: it can be used both to localise and measure the tumour mass through the PET tomography and for the metabolic therapy of the tumour itself. Cu(2.) forms a class of stable classical complexes and chelates with ditio carbamates (DTC), like ethylmethyl-DTC and tiosemicarbazonates, like pyruvaldehyde-bis-(N 4 -methyl semicarbazone (PTSM) and acetyl-bis-(N 4 -methyl semicarbazone) (ATSM), and finally with aza macrocyclic chelants (cyclens, cyclams, sarcofands), like DOTA, DOTP and SarAr). The behaviour of some of them has been already investigated in both cell cultures, rats and humans since the end of the 90-ties

  2. Hydrophilic interaction liquid chromatography coupled to high-resolution mass spectrometry to determine artificial sweeteners in environmental waters.

    Science.gov (United States)

    Salas, Daniela; Borrull, Francesc; Fontanals, Núria; Marcé, Rosa Maria

    2015-06-01

    Artificial sweeteners are food additives employed as sugar substitutes which are now considered to be emerging organic contaminants. In the present study, a method is developed for the determination of a group of artificial sweeteners in environmental waters. Considering the polar and hydrophilic character of these compounds, hydrophilic interaction liquid chromatography is proposed for their separation as an alternative to traditional reversed-phase liquid chromatography. Two stationary phases with different chemistry were compared for this purpose. For the detection of the analytes, high-resolution mass spectrometry (Orbitrap) was employed to take advantage of its benefits in terms of reliable quantification and confirmation for the measurement of accurate masses. Solid-phase extraction was chosen as the sample treatment, in which the extract in a mixture of NH4OH:MeOH:ACN (1:4:15) was directly injected into the chromatographic system, simplifying the analytical procedure. The optimized method was validated on river and waste water samples. For example, in the case of effluent water samples, limits of detection ranged from 0.002 to 0.7 μg/L and limits of quantification ranged from 0.004 to 1.5 μg/L. Apparent (whole method) recoveries ranged from 57 to 74% with intra-day precision (%RSD, n = 5) ranging from 6 to 25%. The method was successfully applied to water samples from different rivers in Catalonia and different waste water treatment plants in Tarragona. Acesulfame, cyclamate, saccharine and sucralose were found in several samples.

  3. Artificial sweeteners--a recently recognized class of emerging environmental contaminants: a review.

    Science.gov (United States)

    Lange, Frank T; Scheurer, Marco; Brauch, Heinz-J

    2012-07-01

    An overview is given of existing trace analytical methods for the determination of seven popular artificial sweeteners [acesulfame (ACE), aspartame, cyclamate (CYC), neotame, neohesperidine dihydrochalcone, saccharin (SAC), and sucralose (SUC)] from aqueous environmental samples. Liquid chromatography-electrospray ionization tandem mass spectrometry and liquid chromatography-electrospray ionization high-resolution mass spectrometry are the methods most widely applied, either directly or after solid-phase extraction. Limits of detection and limits of quantification down to the low nanogram per liter range can be achieved. ACE, CYC, SAC, and SUC were detected in wastewater treatment plants in high microgram per liter concentrations. Per capita loads of individual sweeteners can vary within a wide range depending on their use in different countries. Whereas CYC and SAC are usually degraded by more than 90% during wastewater treatment, ACE and SUC pass through wastewater treatment plants mainly unchanged. This suggests their use as virtually perfect markers for the study of the impact of wastewater on source waters and drinking waters. In finished water of drinking water treatment plants using surface-water-influenced source water, ACE and SUC were detected in concentrations up to 7 and 2.4 μg/L, respectively. ACE was identified as a precursor of oxidation byproducts during ozonation, resulting in an aldehyde intermediate and acetic acid. Although the concentrations of ACE and SUC are among the highest measured for anthropogenic trace pollutants found in surface water, groundwater, and drinking water, the levels are at least three orders of magnitude lower than organoleptic threshold values. However, ecotoxicology studies are scarce and have focused on SUC. Thus, further research is needed both on identification of transformation products and on the ecotoxicological impact of artificial sweeteners and their transformation products.

  4. Thermodynamic studies of the complexation of plutonium(IV) by linear and macrocyclic poly-amino-carboxylate ligands

    International Nuclear Information System (INIS)

    Burgat, Romain

    2007-01-01

    In the framework of a collaboration between the CEA (Commissariat a l Energie Atomique) of Valduc and the ICMUB (Institut de Chimie Moleculaire de l Universite de Bourgogne), a study platform of the structural and physico-chemical properties of the radioelements U, Pu and Am complexes has been implemented. The plutonium(IV) complexation has been studied in a molar nitrate medium. The affinity of three linear poly-amino-carboxylates (EDTA, CDTA and DTPA) towards plutonium(IV) has then been estimated. For the three ligands, the formation constants of the monoleptic complexes Pu(EDTA), Pu(CDTA) and [Pu(DTPA)] - have been determined in a (H,K)NO 3 1 M medium and then extrapolated at a zero ionic force with the specific interactions theory (SIT). For the three complexes, mono-hydroxylated monoleptic species have been observed. With the EDTA and the CDTA, protonated dileptic complexes of a general formula [Pu(L) 2 H h ] (4-h)- have been revealed too. Nevertheless, the steric hindrance around the metallic center is too important to allow to a second molecule of DTPA to coordinate the Pu 4+ cation. The exclusive formation of the species [Pu(DTPA)] - and [Pu(DTPA)(OH)] 2- has been confirmed by capillary electrophoresis (EC-ICP-MS). On account of the preliminary results obtained during the titration of the cyclame tetraacetic product (TETRA) in presence of plutonium(IV), the adding of a competitive ligand such as EDTA has been considered for the study of the complexation of this radioelement by macrocyclic ligands. At last, the affinity of different macrocyclic ligands containing either four amide functions (TETAMMe 2 and TETAMMEt 2 ) or carboxylate groups (TETA, DOTPr and TETPr) towards lanthanides(III) has been estimated too. Although the complexation reaction be fast with the two first ligands, these complexes are less stable than those formed with the carboxylic macrocycles. (O.M.)

  5. Mass loading of typical artificial sweeteners in a pig farm and their dissipation and uptake by plants in neighboring farmland.

    Science.gov (United States)

    Ma, Ling; Liu, Yarui; Xu, Jiayao; Sun, Hongwen; Chen, Hao; Yao, Yiming; Zhang, Peng; Shen, Fengju; Alder, Aldredo C

    2017-12-15

    Pig farm is an important potential source for artificial sweeteners (ASs) in the environment due to their wide use as additives in pig feed. The objective of this study was to evaluate the fate of typical ASs in pig farm and neighboring farmland. For this purpose, the levels of four typical artificial ASs, i.e. saccharin (SAC), cyclamate (CYC), acesulfame (ACE) and sucralose (SUC), in pig feed and manure from a pig farm and water samples from an on-farm wastewater treatment plant (WWTP) in Tianjin, China were measured and the mass loadings and removal efficiencies were assessed. Moreover, the levels of ASs in different layers of soil and vegetables in neighboring farmland that received manure fertilizers and wastewater from the farm were consecutively monitored for 60-80days. The SAC, CYC and ACE were widely determined in all kinds of the samples, while SUC was only found in few soil samples. The mass loadings of the ASs in pig feed were estimated up to 311kg/year for SAC, 59.1kg/year for CYC, and 17.1kg/year for ACE, respectively. The fractions of the total mass of ASs excreted via manure were estimated to be 36.0% for SAC, 59.4% for CYC, and 36.7% for ACE as compared to those in pig feed. High removal efficiencies (>90%) of ASs in the on-farm WWTP was achieved. In greenhouse soils, CYC, SAC, ACE, and SUC were degraded quickly, with half-lives of 4.3-5.9 d, 2.7-4.2 d, 8.4-12.3 d, and 7.3-10.8 d, respectively. Lower levels of ASs were found in deeper soil layer (20-30cm). The ASs were considerably absorbed by plants when the ASs' concentrations were high in soil. This study presents the first comprehensive overview of ASs fate from a pig farm to the neighboring agricultural ecosystem. Copyright © 2017. Published by Elsevier B.V.

  6. Detection of 10 sweeteners in various foods by liquid chromatography/tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    Chui-Shiang Chang

    2014-09-01

    Full Text Available The analytical method for sweeteners in various food matrixes is very important for food quality control and regulation enforcement. A simple and rapid method for the simultaneous determination of 10 sweeteners [acesulfame potassium (ACS-K, aspartame (ASP, cyclamate (CYC, dulcin (DUL, glycyrrhizic acid (GA, neotame (NEO, neohesperidin dihydrochalcone (NHDC, saccharin (SAC, sucralose (SCL, and stevioside (STV] in various foods by liquid chromatography/tandem mass chromatography (LC–MS/MS was developed. The chromatographic separation was performed on a Phenomenex Luna Phenyl-Hexyl (5 μm, 4.6 mm × 150 mm column with gradient elution of 10 mM ammonium acetate in water and 10 mM ammonium acetate in methanol. The recoveries of the 10 sweeteners were between 75% and 120%, and the coefficients of variation were less than 20%. The limits of quantification were 0.5 μg/kg for NHDC and SCL. For the other sweeteners, the limits of quantification were 0.1 μg/kg. Compared to the traditional high-performance liquid chromatography method, the LC–MS/MS method could provide better sensitivity, higher throughput, enhanced specificity, and more sweeteners analyzed in a single run. The samples included 27 beverages (16 alcoholic and 11 nonalcoholic beverages and 15 pickled foods (1 pickled pepper, 3 candies, and 11 candied fruits. Two remanufactured wines were found to contain 7.2, 8.5 μg/g SAC and 126.5, 123 μg/g CYC, respectively. ACS-K, ASP, SCL, and NEO were detected in five beverages and drinks. The pickled peppers and candied fruits were found to contain SAC, GA, CYC, ASP, STV, NEO, and ACS-K. The wine with sweeteners detected was remanufactured wine, not naturally fermented wine. Therefore, the ingredient label for the sweeteners of remanufactured wine should be regulated by the proper authority for inspection of sweeteners.

  7. Estimating the input of wastewater-born micropollutants in a rural karst catchment (Gallusquelle, Germany)

    Science.gov (United States)

    Zirlewagen, Johannes; Hillebrand, Olav; Nödler, Karsten; Schiperski, Ferry; Scheytt, Traugott; Licha, Tobias

    2013-04-01

    cyclamate, contrast media, corrosion inhibitors, pesticides and metabolites of several substances. For analysis of micropollutants, water samples were spiked with internal standards before solid-phase-extraction (SPE) and the analysis was conducted by high-performance liquid chromatographic separation with tandem mass spectrometric detection (HPLC/MS-MS). Quantification limits were in the range of 1-28 ng/l for river water and 200-650 ng/l for untreated wastewater. Once the concentrations and loads of micropollutants in the infiltrating waters are known and compared to those in the spring water, one might distinguish and quantify the portions of water infiltrating from the different sources in the catchment area.

  8. Equivalência de dulçor e poder edulcorante de edulcorantes em função da temperatura de consumo em bebidas preparadas com chá-mate em pó solúvel Equi-sweetness and sweetening power of different sweetening agents in differents temperatures of consumption of tea drink in soluble power

    Directory of Open Access Journals (Sweden)

    Juliana Maria Porto Cardoso

    2004-09-01

    Full Text Available No presente estudo foi verificado o efeito da temperatura de consumo na equivalência de doçura e no poder edulcorante de diferentes agentes adoçantes em bebida de chá-mate em pó solúvel. Foram avaliados: aspartame, sucralose, mistura ciclamato/sacarina 2:1, Stevia e acessulfame-K, tendo como referência a sacarose. Todos os estudos foram realizados a 6±2ºC e a 45±2ºC. Primeiramente foi determinada a doçura ideal, utillizando-se escala do ideal com 30 provadores consumidores da bebida. Em seguida, foi determinada a doçura equivalente à sacarose (na doçura considerada ideal para cada edulcorante estudado, e seu poder edulcorante nas duas temperaturas de estudo. Para tal foi aplicado o método de estimação de magnitude, utilizando-se uma equipe de 10 provadores selecionados e treinados. A doçura ideal de sacarose foi de 8,3% para a bebida de chá-mate solúvel, sem diferença significativa entre as temperaturas de estudo. Ocorreram diferenças sensoriais importantes em função da temperatura, pois, enquanto para alguns edulcorantes o aumento de temperatura provocou diminuição na potência edulcorante, para outros foi observado aumento do poder edulcorante. Portanto, não se deve generalizar as alterações no poder edulcorante em função da temperatura, pois ela pode variar em função da classe química envolvida e do meio de dispersão em que se encontra.In this work the effect of temperature of consumption in the equi-sweetness and sweetening power of different sweetening agents was verified in tea drink in soluble powder. The panelists had evaluated: aspartame, sucralose, mixture of cyclamate/saccharin (2:1, Stevia [Stevia rebaudiana (Bert. Bertoni] and acesulfame-K as sweeteners, having sucrose as reference. All sensory tests were carried-out at 6±2ºC and 45±2ºC. Firstly the ideal sweetness was determined by just-about-right scale with 30 consumers of tea drink. After the ideal sweetness of sucrose determination, the

  9. Utilização de adoçantes dietéticos entre adultos em Pelotas, Rio Grande do Sul, Brasil: um estudo de base populacional Use of diet sweeteners by adults in Pelotas, Rio Grande do Sul State, Brazil: a population-based study

    Directory of Open Access Journals (Sweden)

    Roberta de Vargas Zanini

    2011-05-01

    Full Text Available Estudo de base populacional avaliou o uso de adoçantes dietéticos na população com idade ≥ 20 anos, residente na zona urbana do Município de Pelotas, Rio Grande do Sul, Brasil. A coleta de dados ocorreu entre janeiro e julho de 2010, e 2.732 indivíduos foram entrevistados. Além das questões específicas quanto ao uso de adoçante dietético, foram coletadas informações sobre características demográficas, socioeconômicas e de saúde. Para as análises estatísticas, foram utilizados testes qui-quadrado de heterogeneidade e de tendência linear. A prevalência de uso de adoçante dietético foi 19% (IC95%: 17,1; 20,9, sendo 3,7 vezes maior entre idosos do que entre aqueles com 20-29 anos de idade. Nível econômico e estado nutricional apresentaram associação direta e significativa com o desfecho. Quase 98% da amostra utilizou adoçantes na forma líquida, sendo os mais consumidos (89,2% aqueles constituídos por sacarina e ciclamato de sódio. A mediana de ingestão diária foi 10 gotas (P25; P75 = 6; 18, entre usuários de adoçante líquido, ou 1,5 sachet (P25; P75 = 1; 4, para adoçante em pó. O uso de adoçante dietético foi maior entre mulheres e idosos.This population-based study evaluated the use of diet sweeteners by adults (> 20 years in Pelotas, Rio Grande do Sul State, Brazil. Data were collected from January to July 2010 (n = 2,732. Besides specific questions on diet sweeteners, demographic, socioeconomic, and health characteristics were recorded. Heterogeneity and linear trend chi-square tests were used for the statistical analysis. Prevalence of sweetener use was 19% (95%CI: 1.1-20.9, and was 3.7 times higher in elderly individuals as compared to 20-29-year-olds. Economic level and nutritional status were significantly associated with sweetener use. Nearly 98% of the sample used liquid sweeteners; the most frequently consumed (89.2% were those containing saccharin or sodium cyclamate. Average intake was 10 drops

  10. Kinetic and mechanistic studies of reactive intermediates in photochemical and transition metal-assisted oxidation, decarboxylation and alkyl transfer reactions

    Science.gov (United States)

    Carraher, Jack McCaslin

    leads to the dissociation of H2O2 from Cr(III), while in the H+-independent reaction, CraqOOH2+ is transformed to Cr(V). Both scavengers rapidly remove Cr(V) and simplify both the kinetics and products by impeding formation of Cr(IV, V, VI). Syntheses, Reactivity, and Thermodynamic Considerations LRhR2+. Macrocyclic rhodium(II) complexes LRh(H 2O)2+ (L = L1= cyclam and L2 = meso-Me6-cyclam) react with alkyl hydroperoxides R(CH3)2COOH to generate the corresponding rhodium(III) alkyls LRh(H2O)R2+ (R = CH3, C2 H5, PhCH2). Methyl and benzyl complexes can also be prepared by bimolecular group transfer from alkyl cobaloximes (dmgX) 2(H2O)CoR (where R = CH3, CH2Ph and dmgX is either dimethylglyoxime or a BF2-capped derivative of dmg) to LRh(H2O)2+. When R = C2H5, C3H7 or C4H9, the mechanism changes from group transfer to hydrogen atom abstraction from the coordinated alkyl and produces LRh(H2O)H2+ and an a-olefin. The new LRh(H2O)R2+ complexes were characterized by solution NMR and by crystal structure analysis. They exhibit great stability in aqueous solution at room temperature, but undergo efficient Rh-C bond cleavage upon photolysis. 'Green' Model for Decarboxylation of Biomass Derived Acids via Photolysis of in situ formed Metal-Carboxylate Complexes. Photolysis of aqueous solutions containing propionic acid and Fe 3+ aq in the absence of oxygen generates a mixture of hydrocarbons (ethane, ethylene and butane), carbon dioxide, and Fe2+. Photolysis in the presence of O2 yields catalytic amounts of hydrocarbon products. When halide ions are present during photolysis; nearly quantitative yields of ethyl halides are produced via extraction of a halide atom from FeX2+ by ethyl radical. The rate constants for ethyl radical reactions with FeCl2+ (k = 4.0 (+/- 0.5) x 106 M-1s-1) and with FeBr 2+ (k = 3.0 (+/- 0.5) x 107 M-1s -1) were determined via competition reactions. Irradiation of solutions containing aqueous Cu2+ salts and linear carboxylic acids yield alpha