Chain conformations in the sol–gel transitions for poly-saccharide systems, and their characterisation by spectroscopic methods

摘要: The sol-gel transition has been studied for two polysaccharide systems, which form gels by the noncovalent association of chain segments in ordered conformations, but differ geometry these conformations. For ι-carrageenan they are double helices, formation and melting is monitored [13C]-n.m.r. optical rotation. alginate, associations involve site-binding Ca2+ ions an egg-box or sandwich-like geometry, related to similar structures solid films using circular dichroism spectroscopy. Despite low concentration dispersed (of order 1 %), each gel network a very highly associated structure almost all sequences sugar residues having appropriate covalent permit binding, actually involved binding other chains.