Chiroptical and stoichiometric evidence of a specific, primary dimerisation process in alginate gelation

Microparticulate polyelectrolyte complexes for gentamicin transport across intestinal epithelia

“…The calcium associated to the polymer increased with increasing CaCl 2 concentration used in the preparation (p < 0.05) overcoming in all the samples the theoretical association value (1.1 mol/g polymer, corresponding to ∼ 4.2% calcium), calculated in a previous work for a complete neutralization of the guluronic blocks by calcium ions in a 1:2 calcium/uronic acid molar ratio (Iannuccelli et al, 1996;Morris et al, 1978). Such an overcoming confirms the calcium ability to interact also with alginate mannuronic sequences.…”

Photochemical Patterning of Ionically Cross-Linked Hydrogels

“…These residues are present in the form of homopolymeric GG and MM blocks as well as heteropolymeric GM blocks. In the presence of polyvalent metal cations, particularly Ca 2+ , GG blocks of alginate chains form "egg-box" domains which ionically cross-link two neighboring GG blocks [1][2][3]. The resultant hydrogels are non-immunogenic, porous, and thermally stable.…”

Composition of Alginate Synthesized during the Growth Cycle of Pseudomonas aeruginosa

“…It has been suggested that insoluble Ca 2 +-polysaccharide complexes may contribute to chronic pulmonary obstructions (Dunne and Buckmire 1985) as elevated Ca 2 +levels have been observed in the tracheobronchial secretions of cystic fibrosis patients (Gibson et al 1971). The binding of Ca 2 + by algal alginates has been shown to be almost entirely due to the chelation of the cation by G-block regions of the polymer (Smidsn~d and Haug 1972;Grant et al 1973;Morris et al 1978). It is therefore important to establish whether P. aeruginosa can produce alginates with G blocks and if so under what conditions synthesis of this type of polymer is favoured.…”