Algins fibers

There are several reports on the coating of bone-like hydroxyapatite onto natural polymer substrates. Kawashita et at. [57] reported that carboxymethylated chitin and gellan gum gels, which have carboxyl groups, can form hydroxyapatite on their surfaces in SBF if they are treated with a saturated Ca(OH)2 solution in advance, while curdlan gel, which has no carboxyl group, does not form hydroxyapatite in SBF, even if it is treated with Ca(OH)2 solution. These results support the hypothesis that carboxyl groups induce hydroxyapatite nucleation. Kokubo et at. [58,59] reported that non-woven fabrics of carboxymethylated chitin and alginate fibers also form hydroxyapatite on their surfaces in SBF if they are treated with Ca(OH)2 solution. 

M., Minoda, M., Beppu, T., Miyamoto, T. and Nakamura, T. (2004) Apatiteforming ability of alginate fibers treated with calcium hydroxide solution. Journal of Materials Science-Materials in Medicine, 15, 1007-1012. 

The wet integrity of the dressing which facilitates removal from the wound may be improved by incorporating fibers of greater strength such as viscose (rayon) staple fiber or fibers which interact with the alginate fibers when wet such as chitosan staple fibers. 

A considerable amount of interest has been shown in the ion exchange and adsorption properties of algin and kelp, especially by Mongar and Wasserman (9, 53, 136, 137, lUO, 1J 2, 157,162-164, 237, 281, 282), Fully swollen calcium alginate fibers undergo cation exchange reactions with sodium ions accompanied by axial contraction of the fibers and increase in the cross-sectional diameter (108, 141 f 165),... 

The calcium alginate fibers then can be removed from the finished fabric by washing in alkali. 

Torsdottir, 1., Alpsten, M., Holm, G., Sandberg, A. S., and Tolli, J. (1991). A small dose of soluble alginate-fiber affects postprandial glycemia and gastric-emptying in humans with diabetes. /. Nutr. 121, 795-799. 

Kobayashi, Y.K., Fukuoka, S., Obika, H., Asaoka, T., Tenma, K., 1995. Water Soluble Algin Fibers and Production Thereof. Google Patents. 

Wound healing is a complex process that can be compromised by several factors. The wound healing efficacy of calcium alginate fibers in non-woven pads or ropes as well as in situ formed hydrogels can be further improved by incorporating dmgs or growth factors. 

Qin, Y., and Gilding, R., K., 1996, Alginate fibers and wound dressings. Medic. Device... 

Qin Y (2004) Gel swelling properties of alginate fibers. J Appl Polym Sci 91 1641-1645... 

Chemical or synthetic fibers are further classified into regenerated and synthetic fibers. Regenerated or semisynthetic fibers are produced from natural products by a chemical procedure or modification. These fibers can, for example, be rayon, acetate silk, and alginate fibers. In contrast, synthetic fibers are completely synthesized from other raw materials, and may, for example, consist of polyesters, polyamides, poly(acrylonitrile), polyolefins, or glass. 

Regenerated fibers are fibers produced from material of natural origin. The material undergoes some chemical process or modification (viscose silk, acetate silk, nitrocellulose, alginate fibers, etc.). Synthesized fibers are synthetic fibers completely synthesized from other raw materials. 

A. Khan, T. Huq, M. Saha R.A. Khan, and M.A. Khan, Surface modification of calcium alginate fibers with silane and methyl methacrylate monomers. / Reinf. Plast. Compos. 29 (20), 3125-3132 (2010). 

Alginate fiber n. Fiber formed from a metallic salt (normally calcium) of alginic acid, which is a natural polymer occurring in seaweed. Alginate fiber is soluble in water. 

Qin Y., Alginate fibers An over view of the production processes and applications in wound management , Polym Int, 57(2), 171-180,2008. 

Figure 3 shows the porous structure of a metal alginate. According to the report by Simionescu et al helicoidal portions of alginate chain will be made up of mannuronic acid under hydrochloric acid. In Figure 3 it is clearly observed that under the acid metal alginate fiber net takes the rounded, buckled and twisted form as much as possible and finally changes to a porous cluster form. Sample 4=M-rich is the precipitate at pH 1.5 adjusted with HCl. 

FIGURE 14.1.22 Structure and calcium alginate fiber (top) and scanning electron micrograph of apatite formed on the fiber (left). 

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