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Production of heavy water enriched in oxygen-18
The Synthesis and Applications of Isotopically Labelled Compounds PRODUCTION OF HFAVY WATER ENRICHED IN OXYGEN-18 M.O. Arnold, J.R. Roblns I, P. Connor Stable Isotopes Sectlon, Ontarlo. Hydro, 700 Unlverslty Avenue, Toronto, Ontario, Canada, MSG IX6. IOntarlo Hydro Research D1vlslon, 800 K1pllng Avenue, Toronto, Ontarlo, Canada, M8Z 5S4.
o n t a r i o Hydro i s one of the w o r l d ' s l a r g e s t e l e c t r i c a l u t i l i t i e s
and, In
1987, generated more than half its electricity uslng CANDU Heavy Water Reactors. Hydro also produces all the heavy water required for these reactors. In the final stage of thls productlon, water dlstillatlon Increases the proportion of both deuterium and oxygen-!8. Studies show that the oxygen-18 concentratlon In the hlgh purity heavy water Increases two to three times above natural abundance. We propose to feed the dlst111atlon stage wlth hlgh purity heavy water to increase the oxygen-18 concentration to 3 to 8 atom%. Repeating thls process could produce oxygen Isotope concentrations as hlgh as 50%.
11C/14C KINETIC ISOTOPE EFFECTS B,S, Axelsson, K.-]k. Engdahl, O. Matsson and B. IAngstr0m. Department of Organic Chemistry, Institute of Chemistry, University of Uppsala, P.O. Box 531, S-751 21 Uppsala, Sweden Kinetic isotope effects (KIEs) are powerful tools in the elucidation of organic and enzymatic reaction mechanisms. In thispaper we report on the nC/14C KIE method. There are several advantages in using nC and ~4C in isotope effect studies. Since both isotopes are radioactive (the half-life of llC is 20.34 rain) they can be detected with high precision. The reactions of isotopically labelled molecular species are run in the same reaction pot. At time intervals samples are withdrawn and the reaction is stopped. The samples .aLe . analyzed by HPLC where the labelled reactants and products are separated. The content of l ' C and '4C are measured in the reactant and product fractions. The ratio of the reaction rate constants nk/14k are then calculated from these data. A primary and a secondary KIE has been determined. Preliminary experiments on an enzymatic reaction indicates the presence of a significant carbon isotope effect. SYNTHESIS OF 2-DEOXY-D-GLUCOSE-[2,6,6'-3H] WITH HIGH SPECIFIC ACTIVITY J. DESCHAMPS, B. ROUSSEAU, J.P. BEAUCOURT~ A. VANHOVE CEA-Service des Mol~cules Marquees-91191 GIF-SUR-YVETTE CEDEX FRANCE
2-Deoxy-D-glucose (dG) is us~. as an index of glucose utilization in tissues. High specific activity H-dG is suitable for the exploration o~ brain or cell tissues by autoradiography. Thus, 2-deoxy-D-glucose-[2,6,6'--H] was synthesized with a minimum specific activity of 1.85 TBq/mmol. Tritlolysis of a mixture of methyl l-0-(l-methylethyl)-3,4-di-0-acetyl-2-deoxy-2-bromo-~-D-manno-and D-gluco-pyranosides gave three compounds, including meth~yl l-0-(l-methylethyl)-3,4-di-O-acetyl-2-deoxy-~-D-glucopyranoslduronate-[2-~H] 1 in 57Z yield. Further r~duction of 1 by KBT. followed by hydrolysis gave ~-deoxy-D-glucose-[2,6,6 - H] which Was purlfie~ by preparative paper chromatography and checked by TLC, HPLC, U.V. and -H-NMR spectrometry.
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o n t a r i o Hydro i s one of the w o r l d ' s l a r g e s t e l e c t r i c a l u t i l i t i e s
and, In
1987, generated more than half its electricity uslng CANDU Heavy Water Reactors. Hydro also produces all the heavy water required for these reactors. In the final stage of thls productlon, water dlstillatlon Increases the proportion of both deuterium and oxygen-!8. Studies show that the oxygen-18 concentratlon In the hlgh purity heavy water Increases two to three times above natural abundance. We propose to feed the dlst111atlon stage wlth hlgh purity heavy water to increase the oxygen-18 concentration to 3 to 8 atom%. Repeating thls process could produce oxygen Isotope concentrations as hlgh as 50%.
11C/14C KINETIC ISOTOPE EFFECTS B,S, Axelsson, K.-]k. Engdahl, O. Matsson and B. IAngstr0m. Department of Organic Chemistry, Institute of Chemistry, University of Uppsala, P.O. Box 531, S-751 21 Uppsala, Sweden Kinetic isotope effects (KIEs) are powerful tools in the elucidation of organic and enzymatic reaction mechanisms. In thispaper we report on the nC/14C KIE method. There are several advantages in using nC and ~4C in isotope effect studies. Since both isotopes are radioactive (the half-life of llC is 20.34 rain) they can be detected with high precision. The reactions of isotopically labelled molecular species are run in the same reaction pot. At time intervals samples are withdrawn and the reaction is stopped. The samples .aLe . analyzed by HPLC where the labelled reactants and products are separated. The content of l ' C and '4C are measured in the reactant and product fractions. The ratio of the reaction rate constants nk/14k are then calculated from these data. A primary and a secondary KIE has been determined. Preliminary experiments on an enzymatic reaction indicates the presence of a significant carbon isotope effect. SYNTHESIS OF 2-DEOXY-D-GLUCOSE-[2,6,6'-3H] WITH HIGH SPECIFIC ACTIVITY J. DESCHAMPS, B. ROUSSEAU, J.P. BEAUCOURT~ A. VANHOVE CEA-Service des Mol~cules Marquees-91191 GIF-SUR-YVETTE CEDEX FRANCE
2-Deoxy-D-glucose (dG) is us~. as an index of glucose utilization in tissues. High specific activity H-dG is suitable for the exploration o~ brain or cell tissues by autoradiography. Thus, 2-deoxy-D-glucose-[2,6,6'--H] was synthesized with a minimum specific activity of 1.85 TBq/mmol. Tritlolysis of a mixture of methyl l-0-(l-methylethyl)-3,4-di-0-acetyl-2-deoxy-2-bromo-~-D-manno-and D-gluco-pyranosides gave three compounds, including meth~yl l-0-(l-methylethyl)-3,4-di-O-acetyl-2-deoxy-~-D-glucopyranoslduronate-[2-~H] 1 in 57Z yield. Further r~duction of 1 by KBT. followed by hydrolysis gave ~-deoxy-D-glucose-[2,6,6 - H] which Was purlfie~ by preparative paper chromatography and checked by TLC, HPLC, U.V. and -H-NMR spectrometry.
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