ALGINATE BASED NEW MATERIALS

Present and future applications of alginates are mainly linked to the most striking feature of the alginate molecule; i.e. a sol/gel transit ion in the presence of multivalent cations, e.g. Ca2+, almost independ ent on temperature. These very mild conditions, combined with the fact that alginates are highly characterised and understood both in the li quid and in the gel phase, makes this biopolymer unique compared to ot her gelling polysaccharides. Only pectins resemble alginate in the sol /gel transition behaviour, but this system can hardly be said to be as well characterised and understood as the alginates. The properties of alginate solutions and gels suggest biomedical and pharmaceutical use s. In this paper, the question of the specifications required by a pol ymer for applications in some biomedical areas will be discussed. (C) 1997 Elsevier Science B.V.