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Estimation of carbon‐11 in the atmosphere
International Journal of Environmental Studies, 1988The production of 20 minute C‐11 by interactions of cosmic ray primary and secondary particles with atmospheric nitrogen and oxygen is calculated. We estimate unmeasured C‐11 to be the fifth most active cosmogenic radionuclide in the lower atmosphere with a disintegration rate of 0.014 dpm/m3. Nevertheless, its actual measurement will not prove an easy
Michael J. Tobin, Paul J. Karol
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The use of carbon 11 dioxide for skeletal scintigraphy
The British Journal of Radiology, 1970There is now much evidence to show that scintigraphy is more accurate than radiology for the detection of skeletal metastases (Galasko, Westerman, Li, Sellwood and Burn, 1968; Galasko, 1969a). Opinions differ, however, as to the choice of the isotope. 47Ca, 85Sr, 87Srm and 18F have been the isotopes most commonly used.
C S, Galasko, R R, Coombs, J C, Clark
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Synthesis of carbon-11 labelled diazomethane
International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1987Abstract This work describes a method of synthesis of [ 11 C]diazomethane from [ 11 C]methane. [ 11 C]CH 4 produced by irradiation of a N 2 -5% H 2 mixture with 20 MeV protons is converted into [ 11 C]chloroform by chlorination on pumice stone impregnated with CuCl 2 at 310°C.
C. Crouzel, R. Amano, D. Fournier
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Tumor detection with carbon-11-labelled amino acids
European Journal of Nuclear Medicine, 1984A comparative study of tumor detection with ten 11C-labeled amino acids including four newly synthesized amino acids was carried out to find the most valuable 11C-labeled amino acid for the diagnosis of cancer. 11C-L-methionine showed the highest uptake by the experimental rat hepatoma AH109A (2.7% administered dose/g at 20 min, tumor to blood ratio ...
Kazuo Kubota +14 more
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Fixation of Carbon-11 in the Cells of Proton-irradiated Blood
Nature, 1965WHEN considering the possibility of marking cell populations with a short-lived, positron-emitting nuclide, carbon-11 (11C, T½ = 20.5 min) appears to be suitable because, when produced through nuclear reactions in proton-irradiation of cells, it may be expected to react chemically with the intracellular material in the same way as it does with simpler ...
B, Larsson, S, Graffman, B, Jung
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The preparation of a carbon-11 labelled neurohormone—[11C]melatonin
International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1987Melatonin, a hormone of the pineal gland, has been labelled with the positron-emitting radionuclide, carbon-11 (t1/2 = 20.4 min), for study in vivo by positron emission tomography. Thus a novel labelling agent, [11C]acetyl chloride, was prepared by the carbonation of methylmagnesium bromide with cyclotron-produced [11C]carbon dioxide followed by ...
D, Le Bars +3 more
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Studies to label alfentanil with carbon-11
International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1992Methodology applicable to the synthesis of no-carrier-added [O-methyl-11C]alfentanil was developed. The sequence consisted of [11C]methylation and propionylation of N-aryl-4-(hydroxymethyl)-4-(N-anilino)-piperidines1a and 1c, followed by the chemoselective hydrolysis of bulk byproducts to facilitate isolation of the NCA carbon-11-labeled product by ...
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Carbon-11 acetate as a tracer of myocardial oxygen consumption
European Journal of Nuclear Medicine, 2001Estimation of myocardial oxygen consumption (MVO2) and myocardial blood flow (MBF) is important for the understanding of various (patho)physiological mechanisms and diseases. Clearance rates of carbon-11 labelled acetate, determined with positron emission tomography, allow estimation of MVO2 on a segmental level and non-invasively. In addition, MBF can
L J, Klein +6 more
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Carbon-11 Radiopharmaceuticals - Radiopharmacy Aspects
1992Examples of the routine production of some 11C-labelled PET radiopharmaceuticals which have been set up for patient application are discussed. This includes recommendations and general guidelines for safety and procedures for the a) preparation of the radionuclide and the primary precursors b) synthesis of some secondary precursors c) synthesis ...
C. Halldin, S-O. Nilsson
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Journal of Radioanalytical and Nuclear Chemistry, 1986
An automated continuous flow process has been developed for the synthesis of11C-ethanol and11C-butanol. These alcohols were synthesized via the same route. The reaction of11CO2 with methylmagnesium bromide or with n-propylmagnesium chloride, followed by a lithium aluminum hydride reduction and hydrolysis produced respectively11C-ethanol and11C-butanol.
G. Del Fiore +8 more
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An automated continuous flow process has been developed for the synthesis of11C-ethanol and11C-butanol. These alcohols were synthesized via the same route. The reaction of11CO2 with methylmagnesium bromide or with n-propylmagnesium chloride, followed by a lithium aluminum hydride reduction and hydrolysis produced respectively11C-ethanol and11C-butanol.
G. Del Fiore +8 more
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