Abstract

Alginates are cell-wall constituents of brown algae (Phaeophyceae). They are chain-forming heteropolysaccharides made up of blocks of mannuronic acid and guluronic acid (picture left shows high manuronic acid gel, standard gel and high guluronic gel, giving different consistencies). Composition of the blocks depends on the species being used for extraction and the part of the thallus from which extraction is made. Calcium alginate is insoluble in water and this led to the development of fibres that could be woven into various textiles or parts of textiles, and their use in bandages, particularly for large wounds and burns, became widespread. The bandage could be removed much more easily than cellulose-based bandages, as the calcium alginate was soluble in a simple salt solution, and wound disruption was reduced. Modifications of the same principle also allows these fibres to form an important part of firemen’s fire-proof clothing and as part of the fluxes now used in welding rods. . Good quality stable fibers have been produced from mixed salts of sodium and calcium alginate, and processed into non-woven fabric that is used in wound dressings. They have very good wound healing and haemostatic properties and can be absorbed by body fluids because the calcium in the fibre is exchanged for sodium from the body fluid to give a soluble sodium alginate. This also makes it easy to remove these dressings from large open wounds or burns since they do not adhere to the wound.

A6 SEAWEEDS USED AS A SOURCE OF ALGINATE IN TEXTILE INDUSTRYpdf