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  • 1.
    Antoni, Gunnar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Långström, Bengt
    Asymmetric synthesis of L-2-amino[3-11C]butyric acid, L-[3-11C]norvaline and L-[3-11C]valine.1987In: Acta Chemica Scandinavica, ISSN 0904-213X, E-ISSN 1902-3103, Vol. B41, p. 511-Article in journal (Refereed)
  • 2.
    Antoni, Gunnar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Långström, Bengt
    Synthesis of DL-11C-labelled alanine, 2-aminobutyric acid, norvaline, leucine and phenylalanine and preparation of L-[3-11C]alanine and L-[3-11C]phenylalanine.1987In: Journal of labelled compounds & radiopharmaceuticals, ISSN ISSN 0362-4803, EISSN 1099-1344, Vol. 24, p. 125-Article in journal (Refereed)
  • 3.
    Antoni, Gunnar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Långström, Bengt
    Synthesis of DL-[3-11C]valine using [2-11C]isopropyl iodide and preparation of L-[3-11C]valine by treatment with D-amino acid oxidase.1987In: Int. J. Appl. Radiat. Isot., Vol. 38, p. 655-Article in journal (Refereed)
  • 4.
    Antoni, Gunnar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Långström, Bengt
    Synthesis of gamma-amino[4-11C]butyric acid.1989In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 27, p. 571-Article in journal (Refereed)
  • 5.
    Antoni, Gunnar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Ulin, Johan
    Långström, Bengt
    Synthesis of the 11C-labelled b-adrenargic receptor ligands atenolol, metoprolol and propranol.1989In: The international journal of applied radiation and isotopes, ISSN 0020-708X, E-ISSN 1878-1284, Vol. 40, p. 561-Article in journal (Refereed)
  • 6. Aquilonius, Sten-Magnus
    et al.
    Bergström, Kjell
    Eckernäs, S.A
    Hartvig, Per
    Leenders, K.L.
    Lundkvist, Hans
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Rimland, Annika
    Ulin, Johan
    Långström, Bengt
    In vivo visualization of striatal dopamine reuptake sites using [11C]nomifensine and       positron emission tomography.,1987In: Acta Neurol. Scand., Vol. 76, p. 283-287Article in journal (Refereed)
  • 7. Bergström, Mats
    et al.
    Muhr, Carin
    Lundberg, Per-Ola
    Bergström, Kjell
    Lundkvist, Hans
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Fasth, Karl-Johan
    Långström, Bengt
    Amino acids distribution and metabolism in pituitary adenomas using positron emission  tomography with 11C-L- and D-methionine.1987In: Journal of computer assisted tomography, ISSN 0363-8715, E-ISSN 1532-3145, Vol. 11, p. 384-389Article in journal (Refereed)
  • 8.
    Bergström, Sara K.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Edenwall, Niklas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Lavén, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Velikyan, Irina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Organic Chemistry.
    Långström, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Organic Chemistry.
    Markides, Karin E.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Polyamine deactivation of integrated poly(dimethylsiloxane) structures investigated by radionuclide imaging and capillary electrophoresis experiments2005In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 77, no 3, p. 938-942Article in journal (Refereed)
    Abstract [en]

    The poly(dimethylsiloxane) (PDMS) material provides a number of advantageous features, such as flexibility, elasticity, and transparency, making it useful in integrated analytical systems. Hard fused-silica capillary structures and soft PDMS channels can easily be combined by a tight fit, which offers many alternatives for structure combinations. PDMS and fused silica are in different ways prone to adsorption of low levels of organic compounds. The need for modification of the inner wall surface of PDMS channels may often be necessary, and in this paper, we describe an easy and effective method using the amine-containing polymer PolyE-323 to deactivate both fused-silica and PDMS surfaces. The adsorption of selected peptides to untreated surfaces was compared to PolyE-323-modified surfaces, using both radionuclide imaging and capillary electrophoresis experiments. The polyamine modification displayed a substantially reduced adsorption of three hydrophobic test peptides compared to the native PDMS surface. Filling and storage of aqueous solution were also possible in PolyE-323-modified PDMS channels. In addition, hybrid microstructures of fused silica and PDMS could simultaneously be deactivated in one simple coating procedure.

  • 9.
    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)
  • 10.
    Fast, K J
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Bergström, M
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Hedberg, E
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Cheng, A
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Organic Chemistry.
    Lu, L
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Wu, F
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Bergström, E
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Tolmachev, Vladimir
    Långström, Bengt
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Organic Chemistry.
    76-Br-bromodeoxyuridine marker with PET-preclinical validation studies1997In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 40, no 5, p. 391-393Article in journal (Refereed)
  • 11. Fasth, Karl-Johan
    et al.
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Långström, Bengt
    Asymmetric synthesis of L-[3-11C]alanine and L-[3-11C]phenylalanine by a phase-transfer alkylation reaction.1988In: J. Chem. Perk. Trans. 1, p. 3081-Article in journal (Refereed)
  • 12. Forngren, Benita H
    et al.
    Samskog, Jenny
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry, Analytical Chemistry.
    Gustavsson, Sven Åke
    Tyrefors, Niklas
    Markides, Karin E
    Långström, Bengt
    Reversed-phase ion-pair chromatography coupled to electrospray ionisation mass spectrometry by on-line removal of the counter-ions1999In: J Chromatogr A, Vol. 854, no 1-2, p. 155-162Article in journal (Refereed)
  • 13. 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)
  • 14. 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)
  • 15. Gustavsson, Sven Åke
    et al.
    Samskog, Jenny
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry, Analytical Chemistry.
    Markides, Karin E
    Långström, Bengt
    Studies of signal suppression in liquid chromatography–electrospray ionization mass spectrometry using volatile ion-pairing reagents2001In: J Chromatogr A, Vol. 937, no 1-2, p. 41-47Article in journal (Refereed)
  • 16. Hartvig, Per
    et al.
    Neil, A
    Terenius, Lars
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Rimland, Annika
    Ulin, Johan
    Långström, Bengt
    Brain and plasma  kinetics of the opioid 11C-hydromorphone in two macaque species.,1989In: Pharmacology and toxicology., Vol. 65, p. 214-216Article in journal (Refereed)
  • 17.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Kihlberg, Tor
    Långström, Bengt
    Microscale High-pressure Photochemical Reactor ApparatusManuscript (Other academic)
  • 18.
    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)
  • 19.
    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)
  • 20.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Kihlberg, Tor
    Långström, Bengt
    Synthesis of Aliphatic [carbonyl-11C]Esters Using [11C]Carbon Monoxide2005In: European Journal of Organic Chemistry, ISSN 1434-193X, no 17, p. 3830 - 3834Article in journal (Refereed)
  • 21.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Kihlberg, Tor
    Långström, Bengt
    The Synthesis of [carbonyl -11C]WAY-100635 and Two Analogues Using [11C]Carbon MonoxideManuscript (Other academic)
  • 22.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Långström, Bengt
    Carboxylation of Alkyl Iodides with [11C] and (13C)Carbon Monoxide: Using Sulfoxides as Oxygen NucleophilesManuscript (Other academic)
  • 23.
    Itsenko, Oleksiy
    et al.
    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.
    Photoinitiaed Free Radical Carbonylation Enhanced by Photosensitizers2005In: Organic Letters, Vol. 7, no 21, p. 4661-4664Article in journal (Refereed)
    Abstract [en]

    The enchanicing effect of several photsensitizers in photoinitiated radical carbonylation is demonstrated and applied to acceleate the synthesis of compounds labeled with short-lived 11C. With the sensitizers, the synthesis of [carbonyl-11C]esters and acids from alkyl iodides, [11C]carbon monoxides, alcohols, and water provided up to 75-85% decay-corrected radiochemical yields in 6-min reactions under mild conditions. Acetone was used as a sensitier in preparing 13C-substituted 1,10-decanedicarboxylic acid from (13C)carbon monoxide.

  • 24.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Långström, Bengt
    Photoinitiated Free Radical Carbonylation Enhanced by Photosensitizers2005In: Organic Letters, ISSN 1523-7060, Vol. 7, no 21, p. 4661-4664Article in journal (Refereed)
  • 25.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Långström, Bengt
    Radical-Mediated Carboxylation of Alkyl Iodides with [11C]Carbon Monoxide in Solvent Mixtures2005In: Journal of Organic Chemistry, ISSN 0022-3263, Vol. 70, no 6, p. 2244 - 2249Article in journal (Refereed)
  • 26.
    Itsenko, Oleksiy
    et al.
    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.
    Radical-Mediated Carboxylation of Alkyl iodides with [11C]Carbon Monoxide in Solvent Mixtures2005In: J. Org. Chem, no 70, p. 2244-2249Article in journal (Refereed)
    Abstract [en]

    [carboxyl-11C]Carboxylic acids were prepared from alkyl iodides via photoinitiated radical reactions using 10-8 mol of [11C]carbon monoxide in binary and ternary homogeneous solvent mixtures. Short-(isobutyric), medium-, and long-chain saturated fatty acids (heptadecanoic) were labeled with isolated decay-corrected radiochemical yields ranging from 55% to 70% in 5-7 min reactions. The conversion of [11C]carbon monoxide to products reached 80-90%. To obtain good yields in the reactions performed in water- acetonitrile and water-THF mixtures, the addition of tetrabut-ylammonium hydroxide or potassium hydroxide was essential. The carboxylation was efficient for primary and secondary alkyl iodides. The carboxylation of tertiary iodides was feasible for 1-iodoadamantane but not for tert-butyl iodide. The dependence of the radiochemical yields on reaction time, photoirradiation conditions, and organic and inorganic additives was studied. The method provides a one-step route to [carboxyl-11C]carboxylic acids; traditional methods, in contrast, would require several steps. For example, using the devised reaction, conditions, 3.19 GBq of purified [1-11C]1,10-decanedicarboxylic acid (specific radioactivity 188 GBq/umol) was obtained within 35 min of the end of 10 uAh bombardment. (1-13C)4-Phenylbutyric acid was synthesized using (13C)-carbon monoxide for identifying the labelling position with 1H and 13C NMR.

  • 27. Kirilovas, D
    et al.
    Naessen, T
    Bergström, M
    Petterman, E
    Carlström, K
    Långström, Bengt
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Characterisation of 11C-vorozole in ovarain tissue in rats throughout wstrous cycle in association with conversion of androgens to estrogens in vivo and in vitro2003In: Steroids, no 68, p. 1139-1146Article in journal (Refereed)
  • 28. Kirolovas, D
    et al.
    Naessen, T
    Bergström, M
    Bonasera, T.A
    Bergström-Petterman, E
    Holte, J
    Carlström, K
    Simberg, N
    Långström, Bengt
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Effects of androgens on aromatase activity and 11C-voroxole binding in grnulosa cells in vitro2003In: Acta Obstet. Gynecol. Scand., no 82, p. 209-215Article in journal (Refereed)
  • 29.
    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%.

  • 30.
    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)
  • 31.
    Lavén, Martin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Itsenko, Oleksiy
    Markides, Karin
    Långström, Bengt
    Determination of metabolic stability of positron emission tomography tracers by LC-ESI-MS/MS: an example in WAY-100635 and two analoguesIn: Journal of Pharmaceutical and Biomedical AnalysisArticle in journal (Refereed)
  • 32.
    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.

  • 33.
    Lavén, Martin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Markides, Karin
    Långström, Bengt
    Analysis of microsomal metabolic stability using high-flow-rate extraction coupled to capillary liquid chromatography–mass spectrometry2004In: Journal of Chromatography B, Vol. 806, p. 119-126Article in journal (Refereed)
  • 34. Lavén, Martin
    et al.
    Velikyan, Irina
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Djodjic, Majda
    Ljung, Jenny
    Berglund, Oskar
    Markides, Karin E
    Långström, Bengt
    Wallenborg, Susanne
    Imaging of peptide adsorption to microfluidic channels in a plastic disc using a positron emitting radionuclide2005In: Lab on a chip, Vol. 5, p. 756-763Article in journal (Refereed)
  • 35.
    Lavén, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Velikyan, Irina
    Djodjic, Majda
    Ljung, Jenny
    Berglund, Oskar
    Markides, Karin
    Långström, Bengt
    Wallenborg, Susanne
    Imaging of peptide adsorption to microfluidic channels in a plastic compact disc using a positron emitting radionuclideIn: Lab on a ChipArticle in journal (Refereed)
  • 36.
    Lavén, Martin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Velikyan, Irina
    Djodjic, Majda
    Ljung, Jenny
    Berglund, Oskar
    Markides, Karin
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Långström, Bengt
    Wallenborg, Susanne
    Imaging of peptide adsorption to microfluidic channels in a plastic compact disc using a positron emitting radionuclide2005In: Lab Chip, no 5, p. 756-763Article in journal (Refereed)
    Abstract [en]

    A method for studying peptide-surface interactions within microfluidic channels by radionuclide imaging is described. With the high surface area-to-volume ratio of channels in miniaturised devices, combined with low amunts of analyte, non-specific peptide adsorption is a critical issue. The objective of the study was therefore to develop a method capable of direct detection of adsorbed peptide within microfluidic channels. A micro-device consisting of channels moulded in a plastic compact disc was chosen for the study, together with two selected peptides of different lengths and isolelectric point (pI) values. A bifunctional chelator, DOTA, was attached to the peptide by conjugation and labelled with the short-lived positron emitting radionuclide 68Ga. Quantitative images of radiotracer distribution within the microfluidic channels were obtained using a PhosphorImager system. The power of the method was demonstrated by the ability to clearly measure changes in adsorption when varying a number of parameters that typically affect peptide adsorption. These included surface modifications, analyte concentration, pH, and ionic strength. Additionally, two quantification methods were developed and compared. Radionuclide imaging also permitted visualisation of adsorption and release processes in microchannel chromatographic columns. The results suggest that radionuclide imaging is a suitable tool not only for the study of peptide adsorption to the microchannels presented in this study but also as a versatile tool to measure peptide-surface interactions in a wide variety of miniaturised structures and devices.

  • 37.
    Lavén, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Wallenborg, Susanne
    Velikyan, Irina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Organic Chemistry.
    Bergström, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Djodjic, Majda
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Ljung, Jenny
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Berglund, Oskar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Edenwall, Niklas
    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.
    Långström, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Organic Chemistry.
    Radionuclide Imaging of Miniaturized Chemical Analysis Systems2004In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 76, no 23, p. 7102-7108Article in journal (Refereed)
    Abstract [en]

    We propose radionuclide imaging as a valuable tool for the study of molecular interactions in miniaturized systems for chemical analysis. Sensitive and quantitative imaging can be performed with compounds labeled with short-lived positron-emitting radionuclides, such as C-11 and Ga-68, within selected parts of the system. Radionuclide imaging is not restricted to transparent materials since the relatively energetic positrons can penetrate high optical density materials. Experimentally, a radiotracer is introduced into the object of study, which is subsequently placed on a phosphor storage plate. After exposure, the plate is scanned with a laser and a digital, quantitative image can be reconstituted. To demonstrate the concept, three types of microstructures suited for integration in chemical analysis systems were imaged with C-11- and Ga-68-labeled tracers. The influence of factors such as geometry of the object and type of radionuclide on resolution and sensitivity was investigated. The resolution ranged from 0.9 to 2.7 mm (fwhm). Measuring low amounts of radioactivity in the three structures, 2-20 Bq could be detected, which corresponded to 2.3-500 amol or 2.4-110 pM tracer. The imaging approach was applied to study analyte concentration and sample dilution effects on the performance of a capillary extraction column integrated in an automated LC-ESI-MS system. The utility of the technique was further illustrated by imaging of microchannels in a zeonor plastic compact disk and in a poly(dimethylsiloxane) material for the study of nonspecific peptide adsorption.

  • 38. Lendvai, Gabor
    et al.
    Velikyan, Irina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Bergström, Mats
    Laryea, Daniel
    Välilä, Maria
    Salomäki, Satu
    Långström, Bengt
    Roivainen, Anne
    Biodistribution of 68Ga-labelled phosphodiester, phosphorothioate, and 2'-O-methyl phosphodiester oligonucleotides in normal rats2005In: European Journal of Pharmaceutical Sciences, Vol. 26, p. 26-38Article in journal (Refereed)
  • 39. Lu, L
    et al.
    Samuelsson, Linda
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Bergström, M
    Sato, K
    Fasth, K.J.
    Långström, Bengt
    Department of Biochemistry and Organic Chemistry, Organic Chemistry II.
    Rat studies comparing 11C-FMAU, 18F-FLT and 76Br-BFU as profileration markers2002In: J. Nuc. Med, no 43, p. 1688-1698Article in journal (Refereed)
  • 40. Långström, Bengt
    et al.
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Gullberg, Per
    Halldin, Christer
    New labelled precursors - 11C-alkyl iodides and phosphorous ylides.1984In: Journal of labelled compounds & radiopharmaceuticals, ISSN 0362-4803, E-ISSN 1099-1344, Vol. 21, p. 1207-Article in journal (Refereed)
  • 41. Långström, Bengt
    et al.
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Gullberg, Per
    Halldin, Christer
    Malmborg, Petter
    Någren, Kjell
    Svärd, Hans
    Synthesis of L- and D-[metyl-11C]methionine.1987In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 28, p. 1037-Article in journal (Refereed)
  • 42. Långström, Bengt
    et al.
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Gullberg, Per
    Halldin, Christer
    Någren, Kjell
    Rimland, Annika
    Svärd, Hans
    The synthesis of 1-11C-labelled ethyl, propyl, butyl and isobutyl iodides and examples of alkylation reactions.1986In: Int. J. Appl. Radiat. Isot., Vol. 37, p. 1141-Article in journal (Refereed)
  • 43. Muhr, Carin
    et al.
    Lundberg, Per-Olof
    Bergström, Kjell
    Hartvig, Per
    Lundkvist, Hans
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Långström, Bengt
    Dopamine receptors in pituitary adenomas: PET visualization with 11C-N- methylspiperone.1986In: J. Comp. Ass. Tomograph., Vol. 10, p. 175-180Article in journal (Refereed)
  • 44. Muhr, Karin
    et al.
    Lundberg, Per-Olof
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Bergström, Kjell
    Hartvig, Per
    Lundqvist, Hans
    Stålnacke, Carl-Göran
    Långström, Bengt
    [11C]Bromocriptine uptake in pituitary adenomas. In "Prolactin, Basic and Clinical        correlates". 1985Book (Refereed)
  • 45. Muhr, Karin
    et al.
    Lundberg, Per-Olof
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Bergström, Kjell
    Lundqvist, Hans
    Långström, Bengt
    Positron emissions tomography in patients with pituitary tumours.,1984In: Acta Neurol. Scand., Vol. suppl 98, no 69, p. 26-Article in journal (Refereed)
  • 46. Muhr, Karin
    et al.
    Lundberg, Per-Olof
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Någren, Kjell
    Bergström, Kjell
    Hartvig, Per
    Lundqvist, Hans
    Långström, Bengt
    Stålnacke, Carl-Göran
    The uptake of 11C-labelled bromocriptine and methionine in pitutitary tumours studided by positron emission tomography.1984In: In " Trends in diagnosis and treatment of pituitary adenomas", 151-155 Eds. Lamberts S.W.J. Tilden F.J.H, van Der Veen E.A. and Assies J., Free University press Amsterdam (1984).Article in journal (Refereed)
  • 47. Nordberg, Agneta
    et al.
    Hartvig, Per
    Lundkvist, Hans
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Ulin, Johan
    Långström, Bengt
    Uptake and distribution of (+)-R and (-)-S N-[methyl-11C]nicotine in brains of rhesus    monkey- an attempt to study nicotine receptors in vivo.1989In: J neurol trans 1, p. 195-205Article in journal (Refereed)
  • 48.
    Rahman, Obaidur
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Kihlberg, T.
    Långström, Bengt
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry II. Organisk kemi.
    Synthesis of [11C]/(13C) amines via carbonylation followed by reductive amination2004In: Organic & Biomolecular Chemistry, no 2, p. 1612-1616Article in journal (Refereed)
  • 49.
    Rahman, Obaidur
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Kihlberg, Tor
    Långström, Bengt
    Aryl Triflates and [11C]/(13C)Carbon Monoxide in the Synthesis of 11C-/13C-Amides2003In: Journal of Organic Chemistry, Vol. 68, no 9, p. 3558-3562Article in journal (Refereed)
  • 50.
    Rahman, Obaidur
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Kihlberg, Tor
    Långström, Bengt
    Syntheis of 1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)isoquinoline-3-[11C]carboxamide ([11C-carbonyl]PK11195 and some analogues using [11C]carbon monoxide and 1-(2-chlorophenyl)isoquinolin-3-yl triflate2002In: Journal of the Chemical Society, Perkin Trans. 1, p. 2699-2703Article in journal (Refereed)
12 1 - 50 of 70
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