2-Hydroxyethyl alginate

Early soil-release agents, applied particularly to resin-finished cellulosic goods, were water-soluble polymers, many being related to thickeners (section 10.8) such as starch, hydroxypropyl starch, sodium carboxymethylcellulose, methylcellulose, hydroxyethyl-cellulose, alginates, poly(vinyl alcohol) and poly(vinylpyrrolidone). These functioned essentially as temporary barriers and preferential reservoirs for soil, which was thus easily removed along with the finish in subsequent washing, when they then helped to minimise... 

There have also been some prominent studies of IPNs based on chitin [92, 93], alginate [94], etc. For example, the microscopic incorporation of chitin with methacrylate polymers such as poly(glycidyl methacrylate) [92] and poly(2-hydroxyethyl methacrylate) [93] was achieved by the combination of solution coagulation and bulk polymerization processes (Sect. 3.1.3). From... 

A slightly different approach is to deliver the active drug in a dry powder carrier system, for example microcrystalline cellulose, hydroxyethyl starch, cross-linked dextran, microcrystalline chitosan, carbomer, pectin, or alginic acid. The polymer absorbs water upon contact with the nasal mucosa and swells to become a viscous gel, often demonstrating bioadhesive properties. Such systems can remain in the nasal cavity for as long as six hours. For example, the bioavailability in rats of the somatostatin analogue, octreotide, was shown to be enhanced by the co-administration of alginic acid and cross-linked dextran as dry powders. 

A)H Dextran and alginic acid Hydroxyethyl cellulose and hydroxypropyl cellulose Polyvinyl alcohol, polyhydroxyethyl methacrylate, and low-molecular-weight polyethylene oxide... 

Oechslein, Fricker, and Kissel " studied various powder formulations of mucoadhesive polymers for their efficacy to increase the nasal absorption of octreotide in rats. Although chitosan showed the highest water uptake (chitosan > microcrystalline cellulose > semicrystalline cellulose > pectin = hydroxyethyl starch = alginic acid = Sephadex G25), the highest peptide drug bioavailability was found after coadministration of alginic acid and Sephadex G25 powders (4.1 and 5.56%, respectively). The authors concluded that the calcium-binding properties of the polymers used correlated better with the increased octreotide bioavailability. 

These are high-molecular-weight polymers, either natural or synthetic, such as xanthan gum, hydroxyethyl cellulose, alginates, and carrageenans. In order to understand the role of these thickeners, the gravitational stresses exerted during creaming or sedimentation should be considered ... 

Polymeric thickeners Gums Acacia Alginates Carageenan Chitosan Collagen Tragacanth Xantham Celluloses Sodium carboxymethyl Hydroxyethyl Hydroxypropyl Hyd roxypro pyl m ethyl Acrylic acids Carbomers Polycarbophil Colloidal solids Silica Clays Microcrystalline cellulose Hydrogels Polyvinyl alcohol Polyvinylpyrrolidone Thermoreversible polymers Poloxamers... 

HPC is compatible with most water-soluble gums and resins, and yields homogeneous solutions with MC, hydroxyethyl cellulose (HEC), carboxymelhyl cellulose (CMC), guar, alginate, and locust bean gum, gelatin, sodium caseinate, poly(ethylene oxide), carbowax, etc. (Figure 26.2)... 

Ammonium acrylates copolymer Ammonium alginate Ammonium VA/acrylates copolymer Arabinogalactan Beeswax, synthetic Carboxymethylcellulose sodium Carboxymethyl hydroxyethyl cellulose Carrageenan (Chondrus crispus) Casein Ceresin... 

Bakers yeast extract Baker s yeast glycan Calcium acetate Calcium alginate Calcium carboxymethyl cellulose Calcium carrageenan Calcium chloride Calcium furcelleran Calcium gluconate Calcium glycerophosphate Calcium lactate Calcium sulfate Calcium sulfate dihydrate Carboxymethylcellulose sodium Carrageenan (Chondrus crispus) Carrageenan (Chondrus crispus) extract Cassia gum Cellulose Chitin Chitosan Corn (Zea mays) starch Corn starch, waxy Corn syrup Dextrin Distarch phosphate Ethyl hydroxyethyl cellulose Ferrous sulfate anhydrous Food starch, modified ... 

Rosa glauca, alginates from Laminaria digitata and L. hyperborea, oligosaccharides released by enzymic hydrolysis of agarose, the rhamnomannans and acidic rhamnomannans of Sporothrix schenckii and Ceratocystis stenoceras, and cellulose 0-methyl, 0-carboxymethyl, and 0-hydroxyethyl ethers. Details of the structures of these polymers are included in Part II of this Report. 

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