Edmund T. Bergström

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METHODS With the purpose of developing a PET imaging agent for tumors of the adrenal cortex, we developed syntheses for 11C-etomidate and its methyl analog, 11C-metomidate. (R)-[O-ethyl-1-11C]Etomidate and (R)-[O-methyl-11C]metomidate were prepared by reaction of the appropriate respective 11C-labeled alkyl iodide and the tetrabutylammonium salt of the(More)
[N-methyl-11C]Vorozole, a high-affinity aromatase-binding radiotracer, was synthesized through N-methylation of the corresponding nor-vorozole derivative using [11C]methyl iodide. [N-methyl-11C]Vorozole was obtained in 53-56% radiochemical yield based on [11C]methyl iodide within 40 min of the end of radionuclide production. The final formulation was >98%(More)
Cadmium transfer through and the retention of metal in perfused gills from rainbow trout (Salmo gairdneri) has been studied in the presence of two detergents, LAS (linear alkylaryl sulphonate) and NP-10EO (nonylphenol ethoxylate). Accordingly, the effects of the metal and the surfactants on gill viability (vascular resistance, oxygen diffusion capacity,(More)
A silica monolithic capillary column was linked to an open capillary of the same internal diameter via a Teflon sleeve to form a duplex column to investigate the combination of chromatography and electrophoresis in the mode of electrically assisted capillary liquid chromatography (eCLC). Using a commercial CE instrument with an 8.5 cm long, 100 microm i.d.(More)
A method has been developed for fast evaluation of transesterification activity of immobilized lipases using microlitre and submicrolitre volumes of substrate solutions. The model reaction (acylation of isopropanol with vinyl acetate) is catalyzed by microbial lipases immobilized on ceramic particles, diatoms or acrylic resin, packed into a Teflon tube(More)
The communication demonstrates feasibility of an enzyme microassay for glucose oxidase with 1,4-benzoquinone as an acceptor of electrons. The protocol uses the plug-plug mode of electrophoretically mediated microanalysis, with nanolitre injected volumes of enzyme and reactant solutions. The reactant and product, 1,4-benzoquinone and hydroquinone, are(More)
This paper presents the first study of imaging of spots on thin-layer chromatographic plates whilst still wet with solvent. Imaging and quantification of Sudan II after development with dichloromethane was carried out in both reflectance and transmission modes, using a charge coupled device (CCD) camera. The relationship between peak area and sample loading(More)
Large perfusive silica beads (particle size 110 microm, through pore approximately 2 microm) held in place by the keystone effect were used as single-particle frits for the manufacture of particulate packed capillary columns. High-quality capillary electrochromatographic separations of a standard test mixture of alkylbenzenes were obtained over the full(More)
Highly polar oligosaccharide analytes are notoriously difficult to separate by HPLC without prior derivatization or the use of highly alkaline eluent systems. Using a porous graphitic carbon (PGC) HPLC column, we have studied a pool of endogenous underivatized water-soluble oligosaccharides that were extracted from the stems of a range of wheat cultivars.(More)