Molecular weight, particle size and diffusion coefficient can be determined in many studies by Dynamic Light Scattering, Gel Permeation Chromatography, Analytical Ultracentrifuge, size exclusion chromatography / multiangle laser light scattering / differential viscometry, Flow Field-Flow Fractionation, and so on.ĭetermination of the intrinsic viscosity has been the most used measurement in the last 60 years. Ī lot of research has been devoted to dextrans modification in order to describe special characteristics relevant to specific applications such as surfactants, as visible marker, polysaccharides-based nanoparticles, covalent crosslinking, ionic crosslinking, polyelectrolyte complex, and the self-assembly of hydrophobically modified polysaccharides, and hydrophilic modified polysaccharides. ![]() The particular dextrans which were used initially for conversion into synthetic blood-volume expanders, human red blood cells aggregation for increasing the degree of polymerization and hence the molecular weight, hydrogels and microspheres, in drug transport system and its modifications as nanoparticles, in the removal through absorption of contaminant effluents such as heavy metals, organic molecules and inks, in the formation of biodegradable films. The fast increasing of these polyglucosans for medical, industrial and research purposes motivated a survey of the types obtainable. Dextrans and their derivatives find an interest in clinical applications, as well as excipients in tablets in the pharmaceutical industry. Dextran is soluble in water, methyl sulphoxide, formamide, ethylene glycol, glycerol, 4-methylmorpholine-4-oxide, and hexamethyl phosphamide. The mostly used commercial product/ polysaccharide is dextran, and it is produced from bacterium Leuconostoc mesenteroides, with an overall degree of branching of about 5%. Dextran is a branched polysaccharide, composed of α-D-glucopyranosyl residues. ![]() ![]() A few percent of R (1→3) glucosidic linkages provides side chains which appear to be short. Dextran consists of α-D glucose units with a majority of α (1→6) glucosidic linkages between them.
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