title: Polysaccharide-based polyanion--polycation--polyanion ternary systems. A preliminary analysis of interpolyelectrolyte interactions in dilute solutions.
abstract: The present contribution deals with the preparation and characterization of ternary mixtures of polysaccharides with potential applications in the field of tissue engineering. Two natural polyanions, i.e., alginate and hyaluronic acid, and a polycation, a lactose-modified chitosan (chitlac), were mixed in dilute conditions. The miscibility between the three components was explored in the presence of different amounts of supporting simple salt. These analyses allowed to identify the experimental conditions avoiding polymer phase separation and leading to either solution of independent polymers or soluble nonstoichiometric interpolyelectrolyte complexes. The characterization of the interpolyelectrolyte complexes was tackled by means of viscometry, light scattering, fluorescence quenching, and energy transfer. The electrostatic interactions taking place among the different polyelectrolytes led to synergistic effects on the viscosity of the polymer mixtures which strongly depend on the ionic strength. It has been found that, starting from binary soluble complexes of alginate and chitlac, the addition of hyaluronan led to the dissolution of the complexes. At variance, the addition of alginate to a phase-separated binary mixture of hyaluronan and chitlac led to the formation of soluble complexes composed of all three polysaccharides and, eventually, to their dissolution. In addition, the results showed that at low ionic strength the overall properties of the ternary mixtures depend on their order of mixing.
authors: Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, I-34127 Trieste, Italy. idonati@units.it
authors: Ivan
authors: I
authors: Donati
authors: Massimo
authors: M
authors: Feresini
authors: Andrea
authors: A
authors: Travan
authors: Eleonora
authors: E
authors: Marsich
authors: Romano
authors: R
authors: Lapasin
authors: Sergio
authors: S
authors: Paoletti
mesh_terms: D000464:Alginates / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry; D002236:Carbohydrate Conformation; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry*; D005109:Extracellular Matrix; D031541:Fluorescence Resonance Energy Transfer; D005456:Fluorescent Dyes; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006820:Hyaluronic Acid / Q000737:chemistry*; D007773:Lactates / Q000737:chemistry*; D008958:Models, Molecular; D023822:Tissue Engineering; D014783:Viscosity
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D005456:Fluorescent Dyes; D006603:Hexuronic Acids; D007773:Lactates; D020723:Glucuronic Acid; D006820:Hyaluronic Acid; D048271:Chitosan