INTERMOLECULAR INTERACTIONS IN BIOPOLYMER COMPOSITES STUDIED BY IR SPECTROSCOPY

It is well known that in aqueous solutions sodium alginate - one of the naturally occurring polysaccharides is used as a viscosity former and could be applied in formulation of biocompatible film based drug delivery systems. The addition of mono-and divalent organic acids, as cohesion promoters, in the presence of low concentration of Eudragit (R) E 100 (0,25 divided by 1,5 % w/w) results in increased viscosity, and obviously in their presence creates high transparency self-adhesive films. To examine intermolecular interactions in biopolymer composites containing sodium alginate, Eudragit (R) E 100 and organic acids we measured and compared their IR spectra. It is found that the local mobility of sodium alginate gels in network connections is found to be important, and is essentially slower than that in the micelles created by the alginate itself.