Starch alginate complexes

Ken Jones s first topic of research at Bristol was the elucidation of the structure of damson gum. Maurice Stacey had collected several pounds of the raw material in Shropshire and had donated it to Hirst. The unravelling of the structure of this complex material was a truly formidable task, but Ken was not daunted by this challenge. He rapidly established himself as a leader, building up, with such colleagues as G. T. Young, a powerful carbohydrate-research team, and they extended their interests to other plant gums, alginates, and unusual starches. 

Complexes with Dextrins, Polysaccharide Gums, Alginates, Pectins, and Starch Derivatives... 

This chapter describes the main properties and methods for the characterization of polyelectrolytes derived from the biomass. The most important sources are plants, with cellulose and starch, which turn to polyelectrolytes after chemical modifications. CarboxymethylceUulose is the main cellulose derivative used in many industrial applications as good thickener and hydrophilic polymer for aqueous media. Cationic starches are mainly used in the paper industry for fiUa- retention or paper wet-strength. Natural polyelectrol5des are produced by algae with anionic alginates and carrageenans as the major representatives, which are used in food applications and for biomedical devices. In this respect, alginates are often associated in an electrostatic complex with a pseudo-natural polyelectrolyte (chitosan), a cationic polymer extracted from crustaceous shells. 

Polyelectrolyte, Carbox5methylcellulose, Pectin, Carrageenan, Alginate, Cationic starch, Galactomannan, Lignosulphonate, Ion exchange. Conformational transition. Physical gelation. Electrostatic complex, Chitosan... 

Iodine-metal alginate compound... Sodium alginate reacts with iodine and under acid gives a blue stained adduct like a starch-iodine inclusion complex. In this paper results for film form metal alginate are presented. The effect of pH on the formation of a blue stained adduct is shown in Figure 4A. At about pH 1 the formation reaches the maximum. The amount of the adduct shows an increase with iodine concentration and... 

X-ray fiber diffraction data of film form metal alginate showed broad peaks corresponding to around 7.2A, 8.7A. The characteristic fiber peak observed in the blue stained film prepared at pH 1 corresponds to 3.13A. This value is similar to 3.06A for I-I distance of iodine packed in helical cylinder of starch-iodine inclusion complex. 

For many years, in most cases synthetic polyelectrolytes such as PDADMAC or PEI as PC, and PAC, PAMPS, or PSS as PA were used for complex formation. But at present, the application of so-called natural polymers is of growing importance in the field of complex formation. Natural polymers occur in nature and can be extracted. Examples are chitosan as well as polysaccharides such as starch, pectin, or alginate. Natural polymers are used because of their good biodegradability and high biocompatibility in a wide range of applications in industry. They can have cationic charge (chitosan) [137] or can be modified with cationic as well as hydro-phobic units [74]. 

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