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  • 1.
    Amirkhani, Ardeshir
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Development of Techniques and Methods for the Quantitative Analysis of Endogenous Substances by Microcolumn Liquid Chromatography Coupled to Mass Spectrometry2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Liquid chromatography-mass spectrometry (LC-MS) is a powerful technique for the analysis of endogenous compounds. The introduction of electrospray ionization (ESI) as an interface between LC and MS has contributed strongly to a trend towards miniaturization of LC, due to the possibility to perform ESI at low flow rates. In this thesis, several aspects regarding the design of miniaturized LC systems and electrospray emitters were investigated. In addition miniaturized LC-ESI-MS have been used for the qualitative and quantitative analysis of endogenous polar compounds, peptides and protein digests.

    The performance of miniaturized LC-MS was compared using different electrospray emitter configurations. The results indicated that the efficiency of the LC system is rather independent of the configuration of the emitter.

    The lifetime of gold-coated fused silica electrospray emitters based on vapor deposited adhesion layers of titanium were investigated. The long lifetime of the emitter facilitates the use in LC-MS experiments, exemplified LC-MS by analysis of neuropeptides.

    The ESI voltage is shown to interfere with liquid chromatographic separations performed in packed porous graphitic carbon capillary column. This interference is ascribed to the presence of an electric field over the conductive column in absence of a ground point between the column and the ESI emitter.

    The solid supported enhanced microdialysis for analysis of neuropeptides were compared with conventional microdialysis. The difference between the two methodologies were evaluated by LC-MS analysis of the microdialysates. The solid supported method gave in general higher relative recoveries.

    Finally, a method of standard addition was developed to determine total level of tryptophan and two of its metabolites in human plasma by capillary LC-ESI tandem mass spectrometry. The method was applied in a clinical study of multiple scleroses patients treated with cytokines (IFN Beta 1a, 1b). The results show that the intervention effects the tryptophan metabolism.

    List of papers
    1. Comparison between different sheathless electrospray emitter configurations regarding the performance of nanoscale liquid chromatography time-of-flight mass spectrometry analysis
    Open this publication in new window or tab >>Comparison between different sheathless electrospray emitter configurations regarding the performance of nanoscale liquid chromatography time-of-flight mass spectrometry analysis
    Show others...
    2004 (English)In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1033, no 2, p. 257-266Article in journal (Refereed) Published
    Abstract [en]

    Four different sheathless electrospray ionization (ESI) configurations were investigated for a nano liquid chromatography (LC) system. The studied configurations were: a column with an integrated emitter, with the ESI potential applied before or after the column, and a column with separate emitter, with the ESI voltage applied at a union before the emitter or at the emitter tip. The results indicates that the efficiency of the LC system is rather independent of the configuration when using 95 μm i.d. columns, acetic mobile phase and standard peptides as a sample. Introduction of post column dead volume seems not to be a critical issue at least with flow rates down to 600 nl/min.

    Keyword
    Electrospray ionization, Band broadening, Principal component analysis, Instrumentation, Peptides
    National Category
    Chemical Sciences
    Identifiers
    urn:nbn:se:uu:diva-91889 (URN)10.1016/j.chroma.2004.01.063 (DOI)
    Available from: 2004-05-25 Created: 2004-05-25 Last updated: 2017-12-14Bibliographically approved
    2. Gold-coated fused-silica sheathless electrospray emitters based on vapor-deposited titanium adhesion layers
    Open this publication in new window or tab >>Gold-coated fused-silica sheathless electrospray emitters based on vapor-deposited titanium adhesion layers
    Show others...
    2003 In: Rapid Communication Mass Spectrometry, Vol. 17, no 14, p. 1535-1540Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-91337 (URN)
    Available from: 2004-01-30 Created: 2004-01-30Bibliographically approved
    3. Interference of the electrospray voltage on chromatographic separations using porous graphitic carbon columns
    Open this publication in new window or tab >>Interference of the electrospray voltage on chromatographic separations using porous graphitic carbon columns
    Show others...
    2004 (English)In: Journal of Mass Spectrometry, ISSN 1076-5174, E-ISSN 1096-9888, Vol. 39, no 2, p. 216-222Article in journal (Refereed) Published
    Abstract [en]

    The electrospray ionization (ESI) voltage is shown to interfere with liquid chromatographic separations performed with packed porous graphitic carbon (PGC) capillary columns. This interference is ascribed to the presence of an electric field over the conductive column in the absence of an earth point between the column and the ESI emitter. The current evolved alters the chromatographic behavior of the catecholamine metabolite 3-O-methyl-DOPA significantly, as both peak splitting and a dramatic decrease in the retention time were observed. Furthermore, the response from the mass spectrometer was decreased by 33% at the same time. A related compound, tyrosine, exhibited decreased retention times but no peak splitting, whereas no shifts in the retention times (or peak splitting) were seen for the less retained dopamine and noradrenaline. When the current through the PGC column was eliminated by the use of an earth point between the column and the ESI emitter, the chromatographic behavior of the column was found to return slowly to normal after hours of equilibration with 60 : 40 (v/v) methanol-ammonium formate buffer of pH 2.9. The behavior of the PGC column with and without the earth point was found to be highly reproducible during a period of 1 month. We propose that the effect of the ESI voltage on the chromatographic behavior of the PGC column is due to associated redox reactions affecting both the PGC particles and the analytes. It is concluded that (for analytical reasons), care should be taken to ensure that no current is flowing through the chromatographic system when interfacing PGC columns, and conducting parts in general, to ESI mass spectrometry.

    Keyword
    catecholamine, dopamine, electrochemistry, porous graphitic carbon, electrospray, mass spectrometry, liquid chromatography
    National Category
    Inorganic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-91888 (URN)10.1002/jms.589 (DOI)
    Available from: 2004-05-25 Created: 2004-05-25 Last updated: 2017-12-14Bibliographically approved
    4. A feasibility study of solid supported enhanced microdialysis
    Open this publication in new window or tab >>A feasibility study of solid supported enhanced microdialysis
    Show others...
    2004 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 76, no 6, p. 1678-1682Article in journal (Refereed) Published
    Abstract [en]

    For the first time, a solid supported enhanced microdialysis methodology for analysis of neuropeptides is described. The microdialysis samples were, in this study, subsequently collected in fractions, dissolved from the solid particles, dried, and resolved in a formic acid buffer in order to make them suitable for capillary liquid chromatography-mass spectrometry. Different microdialysis flow profiles were evaluated where air-gapped continuous flow was considered most suitable for the solid supported microdialysis mode. Six endogenous neuropeptides were initially used to investigate the feasibility of this enhanced microdialysis methodology. The improved relative recovery obtained from the solid supported enhanced microdialysis was varying from no effect to 10 times higher as compared to ordinary microdialysis. The most efficient enrichment was obtained for luteinizing hormone releasing hormone, which was the largest but also the most hydrophilic of the peptides. In contrast, no significant difference in recovery was observed for Leu-enkephalin being the smallest and the most hydrophobic peptide tested. These results indicate an increased flux and selective uptake of hydrophilic peptides across the membrane and enrichment on the particles in solid supported microdialysis.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-93181 (URN)10.1021/ac035305l (DOI)15018567 (PubMedID)
    Available from: 2005-05-10 Created: 2005-05-10 Last updated: 2017-12-14Bibliographically approved
    5. Quantitation of tryptophan, kynurenine and kynurenic acid in human plasma by capillary liquid chromatography - electrospray
    Open this publication in new window or tab >>Quantitation of tryptophan, kynurenine and kynurenic acid in human plasma by capillary liquid chromatography - electrospray
    2002 In: Journal of Chromatography B, Vol. 780, no 2, p. 381-387Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-91340 (URN)
    Available from: 2004-01-30 Created: 2004-01-30 Last updated: 2011-03-21
    6. Beta-interferon effects the tryptophan metabolism in the plasma of multiple sclerosis patients
    Open this publication in new window or tab >>Beta-interferon effects the tryptophan metabolism in the plasma of multiple sclerosis patients
    Show others...
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:uu:diva-91341 (URN)
    Available from: 2004-01-30 Created: 2004-01-30 Last updated: 2011-03-21
  • 2.
    Amirkhani, Ardeshir
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Wetterhall, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Nilsson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Danielsson, Rolf
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Bergquist, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Comparison between different sheathless electrospray emitter configurations regarding the performance of nanoscale liquid chromatography time-of-flight mass spectrometry analysis2004In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1033, no 2, p. 257-266Article in journal (Refereed)
    Abstract [en]

    Four different sheathless electrospray ionization (ESI) configurations were investigated for a nano liquid chromatography (LC) system. The studied configurations were: a column with an integrated emitter, with the ESI potential applied before or after the column, and a column with separate emitter, with the ESI voltage applied at a union before the emitter or at the emitter tip. The results indicates that the efficiency of the LC system is rather independent of the configuration when using 95 μm i.d. columns, acetic mobile phase and standard peptides as a sample. Introduction of post column dead volume seems not to be a critical issue at least with flow rates down to 600 nl/min.

  • 3. Andersson, Lars I.
    et al.
    Hardenborg, Emilia
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Physical and Analytical Chemistry, Analytical Chemistry. Analytisk kemi.
    Sandberg-Ställ, Maria
    Möller, Kristina
    Henriksson, Johan
    Bramsby-Sjöström, Inger
    Olsson, Lars-Inge
    Abdel-Rehim, Mohamed
    Development of a molecularly imprinted polymer based solid-phase extraction of local anaesthetics from human plasma2004In: Analytica Chimica Acta, no 526, p. 147-154Article in journal (Refereed)
  • 4.
    Andersson, P.G.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Development of New Methodology for th Preparation of Optically Active Alcohols2004In: Pure Appl. Chem., no 76, p. 547-Article in journal (Refereed)
  • 5.
    Aranyos, Viviane
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Hagfeldt, Anders
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Grennberg, Helena
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Organisk kemi.
    Figgemeier, Egbert
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Electropolymerisable bipyridine ruthenium(II) complexes: synthesis, spectroscopic and electrochemical characterisation of 4-((2-thienyl)ethenyl)-and 4,4'-di((2-thienyl) ethenyl)-2,2'-bipyridine ruthenium complexes2004In: Polyhedron, Vol. 23, p. 589-598Article in journal (Refereed)
    Abstract [en]

    Four new ruthenium polypyridyl complexes with mono- or di-((2-thienyl) ethenyl) substituted bipyridines have been synthesized. The complexes were characterized by NMR, elemental analysis, UV-Vis absorption and electrochemistry (differentioal pulse and cyclic voltammetry). Electroactive polymer films of these complexes have been prepared by oxidative electropolymerisation and characterized by UV-Vis absorption spectroscopy and electrochemistry. The electrochemically induced polymerisation of the complexes resulted in a significant shift of the oxidation potential of the Ru(II)-Ru(III) process towards more positive potentials. Also, MLCT absorption band of the polymeric complexes is shifted towards shorter wavelengths. These results are interpreted in terms of an interrupiton of the conjugated system of the (2-thienyl)ethenyl-substituted bipyridine ligands due to a radical polymerisation mechanism affecting rather the ethenyl part of the ligand than the thienyl.

  • 6.
    Arnaud, Gayet
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry, Organic Chemistry.
    Christelle, Bolea
    Pher G., Andersson
    Development of new camphor based N,S chiral ligands and their application in transfer hydrogenation2004In: Organic & Biomolecular Chemistry, ISSN 1477-0520, Vol. 2, no 13, p. 1887-1893Article in journal (Refereed)
  • 7.
    Baltzer, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    DeGrado, W. F.
    Engineering and design: Expanding the protein world2004In: Editorial overview Current Opinion of Structural Biology, Vol. 14, p. 455-457Article, review/survey (Other (popular scientific, debate etc.))
  • 8. Beletskaya, I.P
    et al.
    Bregadze, V.I.
    Ivushkin, V.A.
    Petrovskii, P.V.
    Sivaev, I.B.
    Sjöberg, Stefan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Zhigareva, G.B.
    New B-substituted derivatives of m-carborane, p-carborane, and cobalt bis(1,2-decarbollide) anion2004In: J. Organomet. Chem., no 689, p. 2920-Article in journal (Refereed)
  • 9. Brandt, Peter
    et al.
    Roth, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Andersson, Pher
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Origin of Enantioselectivity in the Ru(arene)(amino alcohol)-Catalyzed Transfer Hydrogenation of Ketones2004In: J. Org. Chem., no 69, p. 4885-4890Article in journal (Refereed)
    Abstract
  • 10.
    Bruskin, Alexander
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Sivaev, Igor
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Persson, Mikael
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Lundqvist, Hans
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Carlsson, Jörgen
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Sjöberg, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Tolmachev, Vladimir
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Radiobromination of monoclonal antibody using potassium [76Br] (4 isothiocyanatobenzyl-ammonio)-bromo-decahydro-closo-dodecaborate (Bromo-DABI)2004In: Nuclear Medicine and Biology, ISSN 0969-8051, E-ISSN 1872-9614, Vol. 31, no 2, p. 205-11Article in journal (Refereed)
    Abstract [en]

    The use of charged linkers in attaching radiohalogens to tumor-seeking biomolecules may improve intracellular retention of the radioactive label after internalization and degradation of targeting proteins. Derivatives of polyhedral boron clusters, such as closo-dodecaborate (2-) anion, might be possible charged linkers. In this study, a bifunctional derivative of closo-dodecaborate, (4-isothiocyanatobenzyl-ammonio)-undecahydro-closo-dodecaborate (DABI) was labeled with positron-emitting nuclide (76)Br (T 1/2 = 16.2 h) and coupled to anti-HER2/neu humanized antibody Trastuzumab. The overall labeling yield at optimized conditions was 80.7 +/- 0.6%. The label was proven to be stable in vitro in physiological and a set of denaturing conditions. The labeled antibody retained its capacity to bind to HER-2/neu antigen expressing cells. The results of the study demonstrated feasibility for using derivatives of closo-dodecaborate in indirect labeling of antibodies for radioimmunoPET.

  • 11.
    Bökman, C.Fredrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Analytisk kemi.
    Zettersten, Camilla
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Analytisk kemi.
    Sjöberg, Per J.R.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Analytisk kemi.
    Nyholm, Leif
    A Setup for the Coupling of a Thin-Layer Electrochemical Flow Cell to Electrospray Mass Spectrometry2004In: Analytical Chemistry, Vol. 76, no 7, p. 2017-2024Article in journal (Refereed)
    Abstract [en]

    A novel setup for the coupling of commercially available thin-layer cell to electrospray mass spectrometry (ESI-MS) which allows the elctrochemical reactions at the counter electrode to be straightforwardly separated from the flow into the mass spectrometer has been developed. In this way interferences from reaction products formed at the counter electrode can be minimized. This reduces the risk of changes in the mass spectra as a result of electrochemical reactions in the solution. The described setup also enables the working electrode to be positioned close to the electrospray (ESI) emitter without the need for a grounding point or a long transfer line between the electrochemical cell and the electrospray emitter. By decoupling the electrochemical reactions in the flow cell and those in the electrospray emitter, improved facilities for studies of electrochemical reactions are obtained through a better control of the potential of the working electrode. The setup has been used to study the oxidation of a drug (Olsalazine), which previously has been found to involve chemical follow-up reactions. It is also demonstrated that uncharged thiols can be detected in ESI-MS after spontaneous adsorption on a gold working electrode, followed by oxidative desorption to yield sulfinates or sulfonates. This adsorption and potential-controlled desorption has been used for the preconcentration of micromolar concentrations of 1-hexanethiol as well as for desalting of solutions containing micromolar concentrations of thiols. The results indicate that the present on-line coupling of an electrochemical cell to ESI-MS provides promising possibilities for sample preconcentration, matrix exchange (including desalting), and ionization of neutral compounds, such as thiols.

  • 12.
    Büttner, Frank
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Organisk kemi.
    Erdélyi, Máté
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Organisk kemi.
    Arvidsson, Per
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Organisk kemi.
    cyclo(ß-Asp-ß3-hVal-ß3-hLys)-Solid-Phase Synthesis and Solution Structure of a Water Soluble ß-Tripeptide2004In: Helvetica Chimica Acta, Vol. 87, p. 2735-2741Article in journal (Refereed)
  • 13.
    Chajara, Khalil
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Ottosson, Henrik
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    An improved pathway to 6,6-disubstituted fulvenes2004In: Tetrahedron Letters, no 45, p. 6741-6744Article in journal (Refereed)
    Abstract [en]

    Pentafulvenes with alkyl and/or aryl substituents at the exocyclic position are formed rapidly in high yields through reaction of crystalline sodium cyclopentadienide directly with the appropriate ketones.

  • 14. Dybala-Defratyka, Agnieszka
    et al.
    Rostkowski, Michal
    Matsson, Olle
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Westaway, Kenneth C.
    Paneth, Piotr
    A New Interpretation of Chlorine Leaving Group Kinetic Isotope Effects; A Theoretical Approach2004In: J. Org. Chem., Vol. 69, p. 4900-4905Article in journal (Refereed)
    Abstract [en]

    The chlorine leaving group kinetic isotope effects (KIEs) for the SN2 reactions between methyl chloride and a wide range of anionic, neutral, and radical anion nucleophiles were calculated in the gas phase and, in several cases, using a continuum solvent model. In contrast to the expected linear dependence of the chlorine KIEs on the Ca-CI bond order in the transition state, the KIEs fell in a very small range (1.0056-1.0091), even though the Ca-CI transition state bond orders varied widely from approximately 0.32 to 0.78, a range from reactant-like to very product-like. This renders chlorine KIEs, and possibly other leaving-group KIEs, less useful for studies of reaction mechanisms than commonly assumed. A partial explanation for this unexpected relationship between the Ca-CI transition state bond order and the magnitude of the chlorine KIE is presented.

  • 15.
    Enander, Karin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Dolphin, G. T.
    Baltzer, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Designed functionalized helix-loop-helix motifs that bind human Carbonic Anhydrase II- a new class of synthetic receptor molecules2004In: J. Am. Chem. Soc., no 126, p. 4464-4465Article in journal (Refereed)
  • 16.
    Enander, Karin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Dolphin, G.T.
    Liedberg, B.
    Lundström, I.
    Baltzer, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    A versatile polypeptide platform for intergrated recognition and reporting - affinity arrays for protein - ligand interaction analysis2004In: Chem. Eur. J., no 10, p. 2375-2385Article in journal (Refereed)
  • 17.
    Engman, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Organisk kemi.
    Wojtón, A
    Oleksyn, B. J
    Sliwinski, J
    The crystal structure of 2-[N,N-dimethylamino)methyl] benzenetellurenyl chloride2004In: Phosphorus, Sulfur, and Silicon, ISSN 1042-6507, Vol. 179, p. 285-292Article in journal (Refereed)
    Abstract [en]

    The crystal structure of 2-[(N,N-dimethylamino)methyl]benzenetellurenyl chloride (2), a compound previously formulated as bis [[2-(N,N-dimethylamino)methyl]phenyl] ditelluride bis hydrochloride (1a), was determinded. In the molecule 2, tellurium is bonded to the carbon of the phenyl group [2.120(3)Å], the nitrogen o fthe ortho dimethylamino substituent [2.362(3)Å], and the chlorine atom [2.536[1]Å]. There also is an intermolecular interaction of the tellurium atom with the phenyl ring of a neighbouring molecule [3.655(1)Å], resulting in the formation of zigzag chains along the b axis. The noncentorsymmetric space group of the crystal can be explained by the chiral surrounding of tellurium.

  • 18.
    Erdélyi, Máté
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry, Organic Chemistry.
    Towards the Development of Photoswitchable β-Hairpin Mimetics2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Peptide secondary structure mimetics are important tools in medicinal chemistry, as they provide analogues of endogeneous peptides with new physicochemical and pharmacological properties. The β-hairpin motif has been shown to be involved in numerous physiological processes, among others in regulation of eucariotic gene transcription. This thesis addresses the design, synthesis and conformational analysis of photoswitchable β-hairpin mimetics.

    The developmental work included the establishment of an improved procedure for cross coupling of aryl halides with terminal alkynes. Microwave mediated Sonogashira couplings in closed vessels were optimized under homogeneous and solid-phase conditions furnishing excellent yields for a large variety of substrates within 5 – 25 minutes. In addition, microwave heating was shown not to have any non-conventional effect on the reaction rate.

    Furthermore, the most important factors affecting β-hairpin stability were evaluated. Studies of tetrapeptide and decapeptide analogues revealed the essential role of the β-turn in initiation of hairpin folding. Moreover, hydrogen bonding was shown to be the main interchain stabilizing force, whereas hydrophobic interactions were found to be relatively weak. Nevertheless, hydrophobic packing appears to provide an important contribution to the thermodynamic stability of β-hairpins.

    Photoswitchable peptidomimetics were prepared by incorporation of various stilbene moieties into tetra- and decapeptides. Synthesis, photochemical isomerisation and spectroscopic conformational analysis of the compounds were performed.

    List of papers
    1. Rapid Homogeneous-Phase Sonogashira Coupling Reactions Using Controlled Microwave Heating
    Open this publication in new window or tab >>Rapid Homogeneous-Phase Sonogashira Coupling Reactions Using Controlled Microwave Heating
    2001 In: Journal of Organic Chemistry, Vol. 66, no 12, p. 4165-4169Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-91463 (URN)
    Available from: 2004-03-11 Created: 2004-03-11Bibliographically approved
    2. Rapid Microwave Promoted Sonogashira Coupling Reactions on Solid Phase
    Open this publication in new window or tab >>Rapid Microwave Promoted Sonogashira Coupling Reactions on Solid Phase
    2003 (English)In: Journal of Organic Chemistry, Vol. 68, no 16, p. 6431-6434Article in journal (Refereed) Published
    Abstract [en]

    A microwave-enhanced, rapid, and efficient solidphase version of the Sonogashira reaction is presented. It has been applied to the coupling of aryl iodides and bromides with various acetylene derivatives giving excellent yields in 15 to 25 min. The scopes of homogeneous, solventless, and solid-phase conditions for Sonogashira coupling of aryl halides are compared.

    National Category
    Organic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-91464 (URN)10.1021/jo034284s (DOI)
    Available from: 2004-03-11 Created: 2004-03-11 Last updated: 2011-01-05
    3. Insight into β-Hairpin Stability: A Structural and Thermodynamic Study of Diastereomeric β-Hairpin Mimetics
    Open this publication in new window or tab >>Insight into β-Hairpin Stability: A Structural and Thermodynamic Study of Diastereomeric β-Hairpin Mimetics
    2002 In: New Journal of Chemistry, Vol. 26, p. 834-843Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-91465 (URN)
    Available from: 2004-03-11 Created: 2004-03-11Bibliographically approved
    4. Synthesis and Conformational Analysis of Novel Stibene-type Peptidomimetics
    Open this publication in new window or tab >>Synthesis and Conformational Analysis of Novel Stibene-type Peptidomimetics
    Show others...
    Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-91466 (URN)
    Available from: 2004-03-11 Created: 2004-03-11Bibliographically approved
    5. Synthesis and Conformational Analysis of Novel β-Hairpin mimetics. Factors Affecting Stability and Incorporation of a Photoswitchable Dipeptide Mimic
    Open this publication in new window or tab >>Synthesis and Conformational Analysis of Novel β-Hairpin mimetics. Factors Affecting Stability and Incorporation of a Photoswitchable Dipeptide Mimic
    Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-91467 (URN)
    Available from: 2004-03-11 Created: 2004-03-11Bibliographically approved
  • 19.
    Ericsson, Cecilia
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry, Organic Chemistry.
    Synthesis of Tetrahydrofuran and Pyrrolidine Derivatives Utilising Radical Reactions: Organochalcogenides in Reductive, Carbonylative and Group-Transfer Cyclisation2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis describes free-radical reactions for the construction of tetrahydrofuran and pyrrolidine derivatives. The studies are concerned with (i) diastereoselectivity in radical cyclisation, (ii) construction of tetrahydrofuran-3-ones and pyrrolidin-3-ones via radical carbonylation/cyclisation and (iii) synthesis of tetrahydrofuran derivatives via group-transfer cyclisation of organochalcogen compounds.

    (i) Diastereoselectivity in the synthesis of tetrahydrofuran derivatives via radical cyclisation was controlled by addition of Lewis acids. In the synthesis of 2,4-disubstitued tetrahydrofurans, the trans-isomer was formed as the major product in the unperturbed reaction. Upon addition of trialkylalumiums the diastereoselectivity was reversed. In a similar fashion, exo/endo-diastereoselectivity in the synthesis of bicyclic 2,3,4-trisubstituted tetrahydrofurans could also be controlled.

    (ii) Procedures for construction of tetrahydrofuran-3-ones and pyrrolidin-3-ones were presented. Epoxides were ring-opened with benzeneselenolate or benzenetellurolate and the resulting β-hydroxyalkyl phenyl chalcogenides were vinylated using ethyl propiolate/NMM or E-1,2-bis(phenylsulfonyl)ethylene/NaH. The corresponding nitrogen analogues were accessed by N-vinylation of aziridines followed by benzeneselenolate ring-opening. The two types of organochalcogen radical precursors were then treated with TTMSS/AIBN under an atmosphere of carbon monoxide (80 atm) to afford tetrahydrofuran-3-ones and pyrrolidin-3-ones, respectively, in high yields.

    (iii) Microwaves were found to induce group-transfer cyclisation of β-allyloxyalkyl aryl chalcogenides. Short time heating (3-10 min) at 250 oC in ethylene glycol was required to obtain tetrahydrofuran derivatives in 60-91% yield.

    List of papers
    1. Diastereocontrol by Trialkylaluminums in the Synthesis of Tetrahydrofurans via Radical Cyclisation
    Open this publication in new window or tab >>Diastereocontrol by Trialkylaluminums in the Synthesis of Tetrahydrofurans via Radical Cyclisation
    2001 In: Organic Letters, Vol. 3, p. 3459-Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-91437 (URN)
    Available from: 2004-02-26 Created: 2004-02-26Bibliographically approved
    2. Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization
    Open this publication in new window or tab >>Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization
    2002 In: Organic Letters, Vol. 4, p. 3-Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-91438 (URN)
    Available from: 2004-02-26 Created: 2004-02-26Bibliographically approved
    3. Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin-3-ones
    Open this publication in new window or tab >>Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin-3-ones
    2003 In: Journal of Organic Chemistry, Vol. 68, p. 8386-Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-91439 (URN)
    Available from: 2004-02-26 Created: 2004-02-26Bibliographically approved
    4. Microwave-Assisted Group-Transfer Cyclisation of Organotellurium Compounds
    Open this publication in new window or tab >>Microwave-Assisted Group-Transfer Cyclisation of Organotellurium Compounds
    Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-91440 (URN)
    Available from: 2004-02-26 Created: 2004-02-26Bibliographically approved
  • 20.
    Ericsson, Cecilia
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Organisk kemi.
    Engman, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Microwave-Assisted Group-Transfer Cyclization of Organotellurium Compounds2004In: The Journal of Organic Chemistry, Vol. 69, no 15, p. 5143-5146Article in journal (Refereed)
    Abstract [en]

    Primary- and secondary-alkyl aryl tellurides, prepared by arenetellurolate ring-opening of epoxides/O-allylation, were, found to undergo rapid (3-10 min) group-transfer cyclization to afford tetrahydrofuran derivatives in 60-74% yield when heated in a microwave cavity at 250C in ethylene glycol or at 180C in water. To go to completion, similar transformations had previously required extended photolysis in refluxing benzene containing a substantial amount of hexabutylditin. The only drawback of the microwave-assisted process was the loss in diastereoselectivity wich is a consequence of the higher reaction temperature. Substitution in the Te-aryl moiety of the secondary-alkyl aryl tellurides (4-OMe, 4-H, 4-CF3) did not affect the outcome of the group-transfer reaction in ethylene glycol. However, at lower temperature, using water as a solvent, the CF3 derivative failed to react. The microwave-assisted grouptransfer cyclization was extended to benzylic but not to primary- and secondary-alkyl phenyl selenides.

  • 21.
    Eriksson, Jonas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Organic Chemistry.
    Antoni, Gunnar
    Långström, Bengt
    Synthesis of [1-11C]ethyl iodide from carbon monoxide and its application in alkylation reactions2004In: Journal of Labelled Compounds and Radiopharmaceuticals, ISSN 0362-4803, Vol. 47, no 11, p. 723-731Article in journal (Refereed)
  • 22. Forngren, Tobias
    et al.
    Samuelsson, Linda
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Långström, Bengt
    A 11C-methyl stannane (5-[11C]methyl-1-aza-5-stannabicyclo[3.3.3]undecane) for use in palladium-mediated [11C]C-C bond forming reactions with organohalides2004In: Journal of Labelled Compounds and Radiopharmaceuticals, ISSN 1095-6433, Vol. 47, no 1, p. 71-78Article in journal (Refereed)
  • 23. Forngren, Tobias
    et al.
    Samuelsson, Linda
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Långström, Bengt
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    A 11C-methylstannane (5-[11C]methyl-1-aza-5-stannabicyclo[3.3.3] undecane) for use in palladium-mediated [11C]C-Cbond forming reactions with organic halides2004In: J. Labelled Compd. Rad., no 47, p. 71-78Article in journal (Refereed)
  • 24. Frank, Adrian
    et al.
    Danielsson, Rolf
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Selenius, Olle
    Comparison of two monitoring systems for Cu and Mo in the Swedish environment2004In: Science of the Total Environment, no 330, p. 131-143Article in journal (Refereed)
    Abstract [en]

    Bio-geochemical samples (BGS) are roots of certain aquatic plants and mosses suitable for monitoring elements dissolved in stream water. The moose, a wild ruminant living in most parts of Sweden, represents higher trophic level and another manifestation of bioavailability. By analyzing BGS (n=33 600) and moose liver (n=2400), a systematic survey has been performedin the terrestrial environment of Sweden. Cu and Mo are essential elements for life, and their presence is especially important for the Cu-dependent processes in ruminants. The availability of Cu and Mo as monitored in BGS and moose was visualized in the form of maps and subjected to further statistical analysis. The medians, with lower and upper quartiles indicated as intervals, for the country as a whole were: moose liver, Cu=34 (20-59), Mo=0.82 (0.58-1.06) mg kg -1 wet weight; BGS, Cu=50 (35-77), Mo=9.0 (5.3-18.0) mg kg -1 dry weight. The ranges of medians for the 22 Swedish counties were: moose liver, Cu=(20-62), Mo=(0.54-1.18) mg kg -1 wet weight; BGS, Cu=(28-115), Mo=(5-47) mg kg -1 dry weight. The relationships between the counties and the connections between the monitoring variables were elucidated by principal component analysis (PCA). It was demonstrated that two monitoring systems could give divergent results. An unexpectedly strong negative correlation was found between the county medians for Cu in BGS and moose liver. A possible explanation, based on the interaction between Cu and Mo in moose, could not be verified.

  • 25. Frank, Adrian
    et al.
    McPartlin, Joe
    Danielsson, Rolf
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Nova Scotia moose mystery - a moose sickness related to cobalt- and vitamin B12 deficiency2004In: The Science of the Total Environment, no 318, p. 89-100Article in journal (Refereed)
    Abstract [en]

    A wasting, debilitating disease with uncertain aetiology, affecting moose (Alces alces americana) in Eastern North America has been reported repeatedly ever since the 1910s. Despite the intensive studies during 1930-1960s the cause of the sickness could not be established. In the 1960s a parasitic nematode (Parelaphostrongylus tenuis) was reported as constituting a probable explanation for the sickness, although several clinical and pathological signs remained unexplained. In Sweden, a moose disease with similar signs, has been shown to be caused by molybdenosis resulting from a nutritional imbalance. The findings of this investigation were applied in Nova Scotia to determine trace element concentrations in tissues from indigenous moose. Co deficiency was found in about half of the cases and the investigation was complemented by determining the vitamin B12 level, which proved nutritional Co/vitamin B12 deficiency, further verified by an increased MMA (methylmalonic acid) level in plasma. Deficiencies were found mainly in the Tobeatic and Cape Breton Highland regions. No indications of molybdenosis or other trace element disturbances were found in Nova Scotia. Otherwise, extremely high Cd levels (148 mg Cd/kg kidney wet wt., maximum) were found, though probably not contributing to the moose sickness. The Cd burden of moose on mainland Nova Scotia was more than 50% higher than that of moose in Huntville and Alonquin (Ontario, Canada) and five- to six-fold is higher than the highest Cd levels found in Sweden. To counteract the bio-geochemical effects of Co deficiency in the moose environment, provision of Co-containing salt licks is suggested.

  • 26.
    Gayet, Arnaud
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Organisk kemi.
    Bolea, Christine
    Andersson, Pher
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Organisk kemi.
    Development of new camphor based N,S chiral ligands and their application in transfer hydrogenation2004In: Organic & Biomolecular Chemistry, no 2, p. 1887-1893Article in journal (Refereed)
  • 27.
    Ghirmai, Senait
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Synthesis of Organic Compounds for Nuclide Therapy: Derivatives of Carboranes, 9-Aminoacridine and Anthracyclines2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis addresses the synthesis of organic compounds, some of them are derivatives of compounds with DNA binding properties, for potential use in targeted nuclide therapy. The compounds synthesized therefore also need to contain potent nuclides. Here the nuclides considered are the radionuclide 125I, and the stable isotope 10B, which becomes radioactive upon neutron activation. 125I is an Auger-electron emitter, which emits particles that can travel only about 1-2 µm through human tissue and hence has to be delivered to the cancer cell nucleus to cause DNA damage. Neutron activated 10B emits highly cell killing α-particles and 7Li3+ ions, the application of which in Boron Nuclide Capture Therapy (BNCT) has proven very promising.

    The thesis can be divided into three parts:

    i) A nido-carborate, 7-(3´-ammoniopropyl)-7,8-dicarba-nido-undecaborate(-1), has been synthesized and radioiodinated for use as a pendant group for attachment of 125I to tumor-seeking macromolecules. Radiolabeling was achieved in greater than 95% yield.

    ii) Both enantiomers of m-carboranylalanine, a carborane analogue of phenylalanine, have been prepared in high enantiomeric excess, and are of potential interest in BNCT. The synthesis involved amination of the N-acyl derivative formed from [3-(1,7-dicarba-closo-dodecarborane(12)-1-yl)-2-propanoic acid and Oppolzer’s camphor sultam.

    iii) Derivatives of the DNA intercalating compounds 9-aminoacridine, daunorubicin and doxorubicin have been synthesized and labeled with 125I. The 9-aminoacridines were synthesised with a variety of functional groups such as carboxyl, amino and hydroxyl. The anthracylines daunorubicin and doxorubicin are efficient chemotherapeutic agents; the synthesis routes of ester, amide and amine derivatives of these compounds are presented.

    The Chloramine T method was used for the radioiodinations, and the radioiodination precursors of both the acridine and the anthracycline derivatives, were made to contain either a trimethylstannyl group or a phenolic substituent. In the former case the trimethylstannyl group was replaced by 125I, and in the latter case, the compounds were radiolabeled directly at the o- position to the phenolic hydroxyl group. Both methods gave high radiolabeling yields.

    List of papers
    1. Synthesis and Radioiodination of 7-(3´-Ammoniopropyl)-7,8-dicarba-nido-undecaborate(-1), (ANC)
    Open this publication in new window or tab >>Synthesis and Radioiodination of 7-(3´-Ammoniopropyl)-7,8-dicarba-nido-undecaborate(-1), (ANC)
    Show others...
    2004 (English)In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 47, no 9, p. 557-569Article in journal (Refereed) Published
    Abstract [en]

    Derivatives of nido-carborate have potential use in tumour targeting as hydrophilic boron-rich compounds for boron neutron capture therapy (BNCT) and as pendant groups for attachment of radiohalogens to tumour-seeking molecules. For this purpose, functionalized derivatives of nido-carborates that can be conjugated to biomolecules should be synthesized and evaluated. In this study, racemic 1, 7-(3′-ammoniopropyl)-7,8-dicarba-nido-undecaborate(-1) (acronym ANC) was obtained by degradation of the corresponding aminopropyl-o-carborane, which was synthesized in three steps from 1-tert-butyldimethylsilyl-2-(3-bromopropyl)-o-carborane, with sodium hydroxide in absolute ethanol. The racemate 1 was radioiodinated (125I) using the Chloramine-T method. Radio-TLC results showed that radiolabelling with 125I was achieved in a yield greater than 95%.

    National Category
    Organic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-91769 (URN)10.1002/jlcr.840 (DOI)
    Available from: 2004-04-22 Created: 2004-04-22 Last updated: 2017-12-14Bibliographically approved
    2. Enantioselective Synthesis of m-Carboranylalanine a Boron-rich Analogue of Phenylalanine
    Open this publication in new window or tab >>Enantioselective Synthesis of m-Carboranylalanine a Boron-rich Analogue of Phenylalanine
    Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-91770 (URN)
    Available from: 2004-04-22 Created: 2004-04-22Bibliographically approved
    3. Synthesis and Radioiodination of Some 9-Aminoacridine Derivatives
    Open this publication in new window or tab >>Synthesis and Radioiodination of Some 9-Aminoacridine Derivatives
    Show others...
    2004 (English)In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 17, p. 3719-3725Article in journal (Refereed) Published
    National Category
    Organic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-69939 (URN)10.1002/ejoc.200400296 (DOI)
    Available from: 2006-05-17 Created: 2006-05-17 Last updated: 2017-11-21Bibliographically approved
    4. Synthesis and radioiodination of some 9-aminoacridine derivatives for potential use in radionuclide therapy
    Open this publication in new window or tab >>Synthesis and radioiodination of some 9-aminoacridine derivatives for potential use in radionuclide therapy
    Show others...
    2005 (English)In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 48, no 12, p. 855-871Article in journal (Refereed) Published
    National Category
    Organic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-83610 (URN)10.1002/jlcr.960 (DOI)
    Available from: 2006-11-07 Created: 2006-11-07 Last updated: 2017-12-14Bibliographically approved
    5. Synthesis and radioiodination of some daunorubicin and doxorubicin derivatives
    Open this publication in new window or tab >>Synthesis and radioiodination of some daunorubicin and doxorubicin derivatives
    2005 (English)In: Carbohydrate Research, ISSN 0008-6215, E-ISSN 1873-426X, Vol. 340, no 1, p. 15-24Article in journal (Refereed) Published
    Abstract [en]

    Daunorubicin and doxorubicin are efficient agents for cancer treatment. Their clinical efficacy is, however, hampered by their indiscriminant toxicity. This problem may be circumvented by encapsulating the drugs in liposomes and selectively targeting the tumor cells using tumor targeting agents. Furthermore, the antitumor effect could be enhanced by attaching the Auger electron emitter, 125I, to daunorubicin an ddoxorubicin derivatives. In this context a number of ester, amide, and amine derivatives of daunorubicin an ddoxorubicin were synthesized. Benzoic acid ester derivatives of daunorubicin were synthesized by nucleophilic esterification of the 14-bromodaunorubicin with the potassium salt of the corresponding benzoic acid, resulting in good yields. Nicotinic acids and benzoic acids, activated with a succinimidyl group, were coupled to the amino group of daunorubicien to give the corresponding amide derivatives. Amine derivatives were obtained by the reductive amination of aromatic aldehydes with daunorubicin hydrochloride. The stannylated ester and amide derivatives were uses as precursors for radioiodination. Radiolabeling with 125I was performed using chloroamine-T as an oxidant. The optimized labeling resulted in high radiolabeling yields (85-95%) of the radioiodinated daunorubicin and doxorubicin derivatives. Radioiodination of the amines was conducted at the ortho position of the activated phenyl rings providing moderate radiochemical yields (55-75%).

    Keyword
    Daunorubicin, Doxorubicin, Radioiodination, 125I, Chloramine-T
    National Category
    Organic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-70001 (URN)doi:10.1016/j.carres.2004.10.014 (DOI)15620662 (PubMedID)
    Available from: 2006-06-29 Created: 2006-06-29 Last updated: 2017-11-21Bibliographically approved
  • 28.
    Ghirmai, Senait
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Malmquist, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Lundquist, Hans
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Tolmachev, Vladimir
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Sjöberg, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Synthesis and Radioiodination of 7-(3´-Ammoniopropyl)-7,8-dicarba-nido-undecaborate(-1), (ANC)2004In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 47, no 9, p. 557-569Article in journal (Refereed)
    Abstract [en]

    Derivatives of nido-carborate have potential use in tumour targeting as hydrophilic boron-rich compounds for boron neutron capture therapy (BNCT) and as pendant groups for attachment of radiohalogens to tumour-seeking molecules. For this purpose, functionalized derivatives of nido-carborates that can be conjugated to biomolecules should be synthesized and evaluated. In this study, racemic 1, 7-(3′-ammoniopropyl)-7,8-dicarba-nido-undecaborate(-1) (acronym ANC) was obtained by degradation of the corresponding aminopropyl-o-carborane, which was synthesized in three steps from 1-tert-butyldimethylsilyl-2-(3-bromopropyl)-o-carborane, with sodium hydroxide in absolute ethanol. The racemate 1 was radioiodinated (125I) using the Chloramine-T method. Radio-TLC results showed that radiolabelling with 125I was achieved in a yield greater than 95%.

  • 29.
    Ghirmai, Senait
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Mume, Eskender
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Henssen, Cecile
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Ghaneolhusseini, Hadi
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Lundqvist, Hans
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Tolmachev, Vladimir
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Sjöberg, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Orlova, Anna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology, Biomedical Radiation Sciences.
    Synthesis and Radioiodination of Some 9-Aminoacridine Derivatives2004In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 17, p. 3719-3725Article in journal (Refereed)
  • 30.
    Guliashvili, Tamaz
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry, Organic Chemistry.
    Synthesis and Reactivity Studies of Zwitterionic Silenes and 2-Silenolates2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis describes synthesis and reactivity studies of 2-amino-2-siloxysilenes and 2-silenolates, species that are strongly influenced by reversed Si=C bond polarization, i.e. an Siδ-=Cδ+ polarization as compared to the natural Siδ+=Cδ- polarization. Because of the reversed polarization, the 2-amino-2-siloxysilenes are zwitterions and the 2-silenolates are predominantly described by the resonance structure with the negative charge at Si.

    Transient zwitterionic 2-amino-2-siloxysilenes are formed thermolytically from carbamylpolysilanes (tris(trimethylsilyl)silylamides) and trapped with 1,3-dienes in nearly quantitative yields. These silenes have structure and reactivity characteristics that differ from earlier studied Si=C bonded compounds. They are thermodynamically stable toward dimerization and react with 1,3-dienes to give exclusively [4+2] cycloadducts. Their reactions with 1,3-dienes proceed in accordance with inverse electron demand (IED) Diels-Alder reactions which is explained by the electron-rich nature of these silenes. The 2-amino-2-siloxysilenes are also less reactive toward alcohols than earlier silenes. Hence, alcohols do not react with 2-amino-2-siloxysilenes but with the silene precursor, the carbamylpolysilanes, leading to alkoxysilanes in high yields. The latter reaction represents a novel base-free synthetic protocol for protection of primary and secondary alcohols with the fluoride resistant but photolabile tris(trimethylsilyl)silyl group.

    Another class of formally Si=C bonded compounds, metal 2-silenolates, has been formed in high yields using a novel facile method. Reaction of acyl- and carbamylpolysilanes with potassium tert-butoxide in tetrahydrofurane gives potassium 2-silenolates. The potassium 2-silenolates are stable at room temperature, in contrast to earlier lithium 2-silenolates that degrade rapidly at ambient temperature. The first crystallisable complex of a 2-silenolate was formed and characterized by X-ray crystallography. This 2-silenolate has a pyramidal central Si (ΣSi = 317.8°), and an Si-C single rather than Si=C double bond (r(SiC) = 1.926 Å). The potassium 2-silenolates give exclusively Si alkylated products with alkyl halides and only [4+2] cycloadducts with 1,3-dienes.

    List of papers
    1. Evidence for Formation of Silenes Strongly Influenced by Reversed Si=C Bond Polarity
    Open this publication in new window or tab >>Evidence for Formation of Silenes Strongly Influenced by Reversed Si=C Bond Polarity
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    2002 In: Organic Letters, ISSN 1523-7060, Vol. 4, no 11, p. 1915-1918Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-92331 (URN)
    Available from: 2004-11-03 Created: 2004-11-03Bibliographically approved
    2. Formation of Transient Zwitterionic Silenes and Their Diels-Alder Reactions with 1,3-Dienes: Mechanism and Stereoselectivity
    Open this publication in new window or tab >>Formation of Transient Zwitterionic Silenes and Their Diels-Alder Reactions with 1,3-Dienes: Mechanism and Stereoselectivity
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    In: Journal of Americal Chemical Society, ISSN 0002-7863Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-92332 (URN)
    Available from: 2004-11-03 Created: 2004-11-03Bibliographically approved
    3. The First Unsuccesful attempt to Add Alcohols to a Silene
    Open this publication in new window or tab >>The First Unsuccesful attempt to Add Alcohols to a Silene
    In: Organometallics, ISSN 0276-7333Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-92333 (URN)
    Available from: 2004-11-03 Created: 2004-11-03Bibliographically approved
    4. The First Isolable 2-Silenolate
    Open this publication in new window or tab >>The First Isolable 2-Silenolate
    2003 In: Angewandte Chemie International Eddition, ISSN 1433-7851, Vol. 42, no 14, p. 1640-1642Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-92334 (URN)
    Available from: 2004-11-03 Created: 2004-11-03Bibliographically approved
    5. Potassium 1-N,N-Dialkylamino-2,2-bis(trimethylsilyl)-2-Silenolates: Heavy Enolates with Remarkable Stability
    Open this publication in new window or tab >>Potassium 1-N,N-Dialkylamino-2,2-bis(trimethylsilyl)-2-Silenolates: Heavy Enolates with Remarkable Stability
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    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:uu:diva-92335 (URN)
    Available from: 2004-11-03 Created: 2004-11-03 Last updated: 2010-01-13Bibliographically approved
  • 31.
    Gustavsson, S
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Rosén, A
    Grennberg, H
    Bolton, K.
    Computational Studies of Carbon Nanotube-Hydrocarbon Bond Strengths at Nanotube Ends: Effect of Link Heteroatom and Hydrocarbon Structure2004In: Chemistry - A European Journal, Vol. 10, no 9, p. 2223-2227Article in journal (Refereed)
  • 32. Hagman, Charlotte
    et al.
    Ramström, Margareta
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Håkansson, Per
    Bergquist, Jonas
    Quantitative Analysis of Tryptic Protein Mixtures Using Electrospray Ionization Fourier Transform Ion Cyclotron Mass Spectrometry2004In: Journal of Proteome Research, ISSN 1535-3893, Vol. 3, no 3, p. 587-594Article in journal (Refereed)
  • 33.
    Hagman, Charlotte
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Ion Physics. Jonfysik.
    Ramström, Margareta
    Chemistry, Department of Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Ion Physics. analytisk kemi.
    Håkansson, Per
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Ion Physics. Jonfysik.
    Bergquist, Jonas
    Chemistry, Department of Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Ion Physics. Analytisk kemi.
    Quantitative analysis of tryptic protein mixtures using electrospray ionization fourier transform ion cyclotron resonance mass spectrometry2004In: Journal of proteome research, no 3, p. 587-594Article in journal (Refereed)
  • 34.
    Hartikka, Antti
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Organisk kemi.
    Arvidsson, Per
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Rational design of asymmetric organocatalysts-increased reactivity and solvent scope with a tetrazolic acid2004In: Tetrahedron Asymmetry, Vol. 15, p. 1831-1834Article in journal (Refereed)
    Abstract [en]

    Replacement of the carboxylic acid functionality in the widely used organocatalyst proline with a tetrazolic acid leads to a catalyst with increased reactivity and solvent scope, as demonstrated in the direct catalytic asymmetric aldol reaction.

  • 35. Hederos, Sofia
    et al.
    Broo, Kerstin S
    Jakobsson, Emma
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Cell and Molecular Biology. Chemistry, Department of Biochemistry and Organic Chemistry, Biochemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Cell and Molecular Biology, Structural Molecular Biology. ICM.
    Kleywegt, Gerard J
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Cell and Molecular Biology. Chemistry, Department of Biochemistry and Organic Chemistry, Biochemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Cell and Molecular Biology, Structural Molecular Biology. ICM.
    Mannervik, Bengt
    Department of Biochemistry. Chemistry, Department of Biochemistry and Organic Chemistry, Biochemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Cell and Molecular Biology, Structural Molecular Biology.
    Baltzer, Lars
    Department of Chemistry. Chemistry, Department of Biochemistry and Organic Chemistry, Biochemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Cell and Molecular Biology, Structural Molecular Biology.
    Incorporation of a single His residue by rational design enables thiol-ester hydrolysis by human glutathione transferase A1-1.2004In: Proc Natl Acad Sci U S A, ISSN 0027-8424, Vol. 101, no 36, p. 13163-7Article in journal (Refereed)
    Abstract [en]

    A strategy for rational enzyme design is reported and illustrated by the engineering of a protein catalyst for thiol-ester hydrolysis. Five mutants of human glutathione (GSH; gamma-Glu-Cys-Gly) transferase A1-1 were designed in the search for a catalyst and to provide a set of proteins from which the reaction mechanism could be elucidated. The single mutant A216H catalyzed the hydrolysis of the S-benzoyl ester of GSH under turnover conditions with a k(cat)/K(M) of 156 M(-1) x min(-1), and a catalytic proficiency of >10(7) M(-1) when compared with the first-order rate constant of the uncatalyzed reaction. The wild-type enzyme did not hydrolyze the substrate, and thus, the introduction of a single histidine residue transformed the wild-type enzyme into a turnover system for thiol-ester hydrolysis. By kinetic analysis of single, double, and triple mutants, as well as from studies of reaction products, it was established that the enzyme A216H catalyzes the hydrolysis of the thiol-ester substrate by a mechanism that includes an acyl intermediate at the side chain of Y9. Kinetic measurements and the crystal structure of the A216H GSH complex provided compelling evidence that H216 acts as a general-base catalyst. The introduction of a single His residue into human GSH transferase A1-1 created an unprecedented enzymatic function, suggesting a strategy that may be of broad applicability in the design of new enzymes. The protein catalyst has the hallmarks of a native enzyme and is expected to catalyze various hydrolytic, as well as transesterification, reactions.

  • 36.
    Ikegami, Hidetsugu
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Pettersson, Roland
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Einarsson, Lars
    Interfaculty Units, The Svedberg Laboratory.
    Enormous Entropy Enhancement Revealed in Linked Nuclear and Atomic Li + D Fusion in Metallic Li Liquid2004Report (Other scientific)
  • 37.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Kihlberg, Tor
    Långström, Bengt
    Photoinitiated Carbonylation with [11C]Carbon Monoxide Using Amines and Alkyl Iodides2004In: Journal of Organic Chemistry, ISSN 0022-3263, Vol. 69, no 13, p. 4356-4360Article in journal (Refereed)
  • 38.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Kihlberg, Tor
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Långström, Bengt
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Photoinitiated Carbonylation with [11C]Carbon Monoxide Using Amines and Alkyl Iodides2004In: J. Org. Chem., no 69, p. 4356-4360Article in journal (Refereed)
  • 39. Jansson, Christer
    et al.
    Pihlström, Tuija
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Österdahl, Bengt-Göran
    Markides, Karin E
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    A new multi-residue method for analysis of pesticide residues in fruit and vegetables using liquid chromatography with tandem mass spectrometric detection2004In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1023, no 1, p. 93-104Article in journal (Refereed)
    Abstract [en]

    A new multi-residue method for determination of pesticide residues in a wide variety of fruit and vegetables, using the National Food Administration (NFA) ethyl acetate extraction and determination by means of LC-MS/MS, is presented. The method includes pesticides normally detected by LC-UV or LC-fluorescence such as benzimidazoles, carbamates, N-methylcarbamates and organophosphorus compounds with an oxidisable sulphide group as well. After extraction with ethyl acetate, the extract is concentrated and an aliquot of the extract is evaporated to dryness and redissolved in methanol before injection on LC-MS/MS. The method has been validated for 57 different pesticides and metabolites. Representative species from different commodity groups were chosen as matrices in order to study the influence from different matrices on recoveries. The fortification levels studied were 0.01-0.5 mg kg(-1). Matrix effects were tested for all matrices by means of standard addition to blank extracts. The matrix effect, expressed as signal in solvent compared to signal in matrix, was in general found to be small. The obtained recoveries are, with a few exceptions, in the range 70-100%. The proposed method is quick and straightforward and no additional clean-up steps are needed. The method can be used for the analysis of all 57 pesticides in one single determination step at 0.01 mg kg(-1).

  • 40.
    Johannesson, Nina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Wetterhall, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Markides, Karin E.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Bergquist, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Monomer surface modifications for rapid peptide analysis by capillary electrphoresis and capillary electrochromatography coupled to electrospray ionization mass spectrometry2004In: Electrophoresis, ISSN 0173-0835, E-ISSN 1522-2683, Vol. 25, no 6, p. 809-816Article in journal (Refereed)
    Abstract [en]

    In this study, positively charged alkylaminosilyl monomers were used to modify the inner surface of fused silica capillaries, which subsequently were employed in capillary electrophoresis (CE) and capillary electrochromatography (CEC). The obtained surfaces yield a reversed electroosmotic flow (EOF) and have varying carbon chain lengths, that interact with the analytes and give chromatographic retention. The coating procedure is very simple and fast. The performance of the modified capillaries was evaluated regarding pH influence on EOF and chromatographic interactions. The experiments were conducted with UV and mass spectrometry (MS) and applied to the separation of various neuropeptides. The derivatized surfaces showed a linear (R2 ∼0.99) pH dependence with isoelectric points (pI) at 8.6–8.8. Rapid separations of peptide standards and a protein digest with efficiencies as high as 5×105 plates/m were performed.

  • 41. Johansson, Olof
    et al.
    Wolpher, Henriette
    Borgström, Magnus
    Hammarström, Leif
    Bergquist, Jonas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Sun, Licheng
    Åkermark, Björn
    Intramolecular charge separation in a hydrogen bonded tyrosine-ruthenium(II)-naphthalane diimide triad2004In: Chem. Commun., p. 194-195Article in journal (Refereed)
    Abstract [en]

    Long-lived charge-separated states in the ns to us range were observed upon laser flash excitation of a donor-chromophore-acceptor triad based on tris(bipyridine) ruthenium(II) as photosensitizer, naphthalene diimide as acceptor, and a hydrogen bonded phenol as donor.

  • 42. Johansson, Olof
    et al.
    Wolpher, Henriette
    Borgström, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Hammarström, L.eif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Bergquist, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Sun, Licheng
    Åkermark, Björn
    Intramolecular charge separation in a hydrogen bonded tyrosine-ruthenium(II)-naphthalene diimide triad2004In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, no 2, p. 194-195Article in journal (Refereed)
    Abstract [en]

    Long-lived charge-separated states in the ns to [micro sign]s range were observed upon laser flash excitation of a donor-chromophore-acceptor triad based on tris(bipyridine) ruthenium(ii) as photo-sensitizer, naphthalene diimide as acceptor, and a hydrogen bonded phenol as donor.

  • 43.
    Kushnir, Mark M
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry, Analytical Chemistry.
    Nielson, Rebecka
    Roberts, William L
    Rockwood, Alan L
    Cortisol and cortisone analysis in serum and plasma by atmospheric pressure photoionization tandem mass spectrometry: Cortisol and cortisone analysis LC-MS/MS2004In: Clinical Biochemistry, ISSN 0009-9120, Vol. 37, no 5, p. 357–362-Article in journal (Refereed)
  • 44.
    Kushnir, Mark M
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry, Analytical Chemistry.
    Rockwood, Alan L
    Nelson, Gordon J
    Simultaneous quantitative analysis of isobars by tandem mass spectrometry from unresolved chromatographic peaks: Quantitation of isobars from unresolved chromatographic peaks2004In: Journal of Mass Spectrometry, ISSN 1096-9888, Vol. 39, no 5, p. 532-540Article in journal (Refereed)
  • 45.
    Källström, Klas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Hedberg, Christian
    Brandt, Peter
    Bayer, Annette
    Andersson, Pher
    Rationally Designed Ligands for Asymmetric Iridium-Catalyzed Hydrogenation of Olefins2004In: Journal of the American Chemical Society, ISSN 0002-7863, Vol. 126, no 44, p. 14308-14309Article in journal (Refereed)
    Abstract
  • 46.
    Källström, Klas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Hedberg, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Brandt, Peter
    Bayer, Annette
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Andersson, Pher
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Rationally Designed LIgands for Asymmetric Iridium-Catalyzed Hydrogenation of Olefins2004In: J. Am. Chem. Soc., no 126, p. 14308-14309Article in journal (Refereed)
    Abstract
  • 47. Källström, Klas
    et al.
    Hedberg, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Brandt, Peter
    Bayer, Annette
    Andersson, Pher G.
    Rationally Designed Ligands for Asymmetric Iridium-Catalyzed Hydrogenation of Olefins2004In: Journal of the American Chemical Society, ISSN 0002-7863, Vol. 126, no 44, p. 14308-14309Article in journal (Refereed)
    Abstract
  • 48.
    Lavén, Martin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Appel, L.
    Moulder, Robert
    Tyrefors, Niklas
    Markides, Karin E.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Långström, Bengt
    Determination of flumazenil in human plasma by liquid chromatography - electrospray ionisation tandem mass spectrometry2004In: Journal of Chromatography B, no 808, p. 221-227Article in journal (Refereed)
    Abstract [en]

    A liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS/MS) method was developed to determine unlabelled flumazenil (Ro 15-1788) in human plasma in (11 C)flumazenil positron emission tomagraphy (PET) studies.

    N-Methyl tri-deuterated flumazenil was used as an internal standard. The analyte and internal standard were extracted from plasma samples using solid-phase extraction, with a recovery of 78%. This was determined through the convenience of radioactivity measurements of 11 C-labelled flumazenil. The evaporated and reconstituted eluate was analysed by LC-ESI-MS/MS. The calibration curve was linear over the tested concentration range of 0.05-0.5 nM (15-150 pg/ml) with a correlation coefficient, R 2, of 0.998 +- 0.001. A high precision was achieved, with mean intra-assay and inter-assay relative standard deviations of at most 6 and 7%, respectively. The accuracy of the method ranged from 95 to 104%. As a proof of concept, the validated method was applied in the determination of flumazenil in plasma from two healthy volunteers participating in a PET study with three repeated investigations. A bolus-infusion protocol was used to achieve a constant concentration level of flumazenil. The average plasma concentrations ranged from 0.11 and 0.19 nM and all measurements were within the calibration standard range. The flumazenil concentrations were relatively constant within each scan and the average intra-scan precision was 15%.

  • 49.
    Lavén, Martin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Appel, Lieuwe
    Moulder, Robert
    Tyrefors, Niklas
    Markides, Karin
    Långström, Bengt
    Determination of flumazenil in human plasma by liquid chromatography - electrospray ionisation - tandem mass spectrometry2004In: Journal of Chromatography B, Vol. 808, p. 221-227Article in journal (Refereed)
  • 50.
    Lavén, Martin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Markides, Karin E.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Långström, Bengt
    Analysis of microsomal metabolic stability using high-flow-rate extraction coupled to capillary liquid chromatography-mass spectrometry2004In: Journal of Chromatography B, no 806, p. 119-126Article in journal (Refereed)
    Abstract [en]

    A method described for on-line high-speed extraction of microsomal samples and analysis by capillary liquid chromatography - mass spectrometry (LC-MS) for the determination of metabolic stability in connection with the development of positron emission tomography (PET) tracers. the method allowed direct injections of large sample volumes at a fast extraction rate, providing a gain in both sensitivity and sample preparation time. The calibration curve of the test compound flumazenil (Ro 15-1788) was linear in the concentration range of 1-150 nM, with a correlation coefficient exceeding 0.999. The accuracy of the method ranged from 98 to 101%. A high precision was obtained, with mean intra-assay and inter-assay relative standard deviations of at most 1.4 and 1.5%, respectively, for quality control (QC) samples. The extraction efficiency was determined to be 99.4%, the total recovery 96% and the carryover to <0.23%. Extractions were performed in a concentration interval of 30-300 nM without any sign of column overload. The method was successfully used for determining the microsomal metabolic stability of flumazenil. As a result, the described analysis system is currently used for metabolic screening of PET tracer candidates in our laboratory.

123 1 - 50 of 117
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