Preparation and sorption properties of a beta-cyclodextrin-linked chitosanderivative

beta -Cyclodextrin (beta -CD) was coupled to chitosan by the intermediate o f its monochlorotriazinyl derivative, called beta W7MCT, so that a chitosan derivative bearing cyclodextrin was obtained. Because the average degree o f substitution of the cyclodextrin derivative was 2.8, the reaction yielded crosslinked insoluble products. The structure of these materials has been investigated by high-resolution magic-angle spinning (HRMAS) with gradients . For the first time, HRMAS spectra of chitosan polymers containing beta -C D were obtained. This NMR technique produced one- and two-dimensional well- resolved solid-state spectra. These data confirm the proposed structure. De contamination of waters containing textile dyes were carried out with the c rosslinked derivatives. These tests showed that the new chitosan derivative s are characterized by a rate of sorption and a global efficiency superior to that of the parent chitosan polymer and of the well-known cyclodextrin-e pichlorohydrin gels. (C) 2000 John Wiley & Sons, Inc.