Gelation of alginate

Fig. 5.5 (A) Alginate block copolymer structure with random sequences (B) divalent cations induced gelation of alginate (formation of egg-box structure).

The principle took advantage of the gelation of alginate at room temperatures in the presence of calcium ions. Recently, a new method was described by Alleyene et al. [16] based on a microcube concept, and compared with older methods. 

Toft, K., Grasdalen, H., and Smidsrod, O. (1986). Synergistic gelation of alginates and pectins. In Chemistry and Function of Pectins, ACS Symposium Series 310, pp. 117-132. Am. Chem. Soc., Washington, DC. 

Substantial research efforts have been made to relate molecular properties to the structures of the junction zones and provide mechanisms for gel formation. Thus we have models for the formation and alignment of double helices for kappa-carrageenan, formation of triple helices for gelatin and egg box models for calcium induced gelation of alginate and pectin to mention a few examples (Morris 1986 Djabourov... 

Swelling, Drug Release. - Gelation of alginate by external Ba " (or other... 

Yotsuvanagi, T., T. Ohkubo, T. Ohhashi and K. Ikeda, Calcium-induced gelation of alginic acid and pH-sensitive reswelling of dried gels, Chem. Pharm. Bull., 35 (1987) 1555-1563. 

Effects of gelation of alginate around chymotiypsin on reactivities... 

Key words Reactivities of chymotrypsin - gelation of alginate - immobilized enzyme - effects of gelation capsule... 

Alternatively, UCST behavior in water can be achieved based on the interactions between a polyelectrolyte with multivalent counterions as has been described for solutions containing poly(dimethylamino ethyl methacrylate) with the trivalent anion [Co(CN)g] (Plamper et al, 2007). Despite the hydrogelation of polyelectrolytes in the presence of multivalent ions being commonly known, such as the gelation of alginate in the presence of calcium(II), there are few studies focusing on the UCST type phase transitions of such hydrogels or polymer solutions. The synthesis of such vinyl polymers can be performed by radical polymerization, as discussed in Section 2.3.1. 

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