Dextran synthetic

Dextrans are bacterial and yeast polysaccharides made up of (a 1—>6)-linked poly-D-glucose all have (al—>3) branches, and some also have (al—>2) or (al—>4) branches. Dental plaque, formed by bacteria growing on the surface of teeth, is rich in dextrans. Synthetic dextrans are used in several commercial products (for example, Sephadex) that serve in the fractionation of proteins by size-exclusion chromatography (see Fig. 3-18b). The dextrans in these products are chemically cross-linked to form insoluble materials of various porosities, admitting macromolecules of various sizes. 

From this data it was calculated that the dextran used contains 10% irregularities. Moreover, from the close agreement between the observed periodate consumption and that calculated from the formic acid production, it may be concluded that these irregularities can be assigned as linked glucoside units. Khomyakov concluded from periodate oxidation studies on dextrans, synthetized by Leu-conostoc mesenteroides species, that in addition to a(l- 6) linkages a certain number of l->-3 and links were present. However... 

Long-time reproducibility of elution profiles broad standard calibration with dextran T-500 transformation of a scb-type calibration function into nb/Icb-type via universal calibration dp of synthetic glucans in the presence of significant amounts of monomer mass and molar degree of polymerization of Triticale (hybride) starch... 

In addition to polymer standards, a number of broad distribution, water-soluble polymers can be characterized on TSK-PW columns using universal calibration. These include both fully and partially hydrolyzed PVA, PAAM, PEE, and dextran. PVA, the world s largest-volume, synthetic, water-soluble polymer, was first successfully separated on TSK-PW columns by Hashimota et al. (10). In the 1980s, the use of low-angle, laser light-scattering detection... 

Dextran is the first microbial polysaccharide produced and utilized on an industrial scale. The potential importance of dextran as a structually (and property) controlled feedstock is clearly seen in light of the recent emphasis of molecular biologists and molecular engineers in the generation of microbes for feedstock production. Dextran is employed as pharmaceuticals (additives and coatings of medications), within cosmetics, as food extenders, as water-loss inhibitors in oilwell drilling muds and as the basis for a number of synthetic resins. 

The supports employed for covalent attachment of enzymes can be classified into two groups a) natural (agarose, dextran, cellulose, porous glass, silica, the optical fiber itself or alumina) and b) synthetic (acrylamide-... 

There is a number of synthetic substitutes for natural ferritin and the properties of these have been compared with those of ferritin. The synthetic polysaccharide iron complex (PIC), has a magnetic blocking temperature of 48K (Mohie-Eldin et al. 1994). Iron-dextran complexes are used as a substitute for ferritin in the treatment of anaemia. The iron cores of these complexes consist not of ferrihydrite, but of very poorly crystalline akaganeite with magnetic blocking temperatures of between 150 and 290 K (Muller, 1967 Knight et al. 1999) which were lowered from 55K to 35 and 25K, if prepared in the presence of 0.250 and 0.284 Al/(A1 -i- Fe), respectively (Cheng et al.2001). 

An example of the synthesis of an adriamycin-dextran-antibody (anticarcino-embryonic mAb) is shown in Fig. 9 [54]. The synthetic design called for the modification of all three components, i.e., drug, polymeric carrier, and antibody before conjugation. 

Fractionation of the synthetic polysucrose Ficoll (manufactured by Pharmacia AB, Uppsala, Sweden) was achieved by Laurent and Granath56 by the method already described for dextran. From material having a broad distribution of molecular weight, several fairly homo-... 

Snezhkova E, MuUer D, Bardakhivskaya K et al (2004) Synthetic activated carbon as a possible matrix for dextran-sulfate immobilization. Biomater Artif Cells Artif Organs 32(4) 529-537... 

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