New supramolecular assemblies of a cyclodextrin-grafted chitosan through specific complexation

New supramolecular assemblies based on a chitosan bearing pendant cyclodextrins were prepared. For this purpose, adamantyl groups which can selectively be included in the cyclodextrin cavity were grafted on chitosan and various poly(ethylene glycol)s (M-n = 3400, 6000, 20000) affording guest macromolecules with different structural features. The specific interaction of the latter with CD-chitosan through inclusion complex formation was examined by rheological measurements. Physical cross-linking between CD-chitosan chains was shown to occur, leading to large increase of the viscosity or gel-like behavior, depending on the guest.