An improved method for synthesizing N,N′-dicarboxymethylchitosan

Fully substituted N,N'-dicarboxymethylchitosan was obtained by the alkylation of chitosan at pH 8-8.5 and 90 degrees C using a monochloroacetic acid:chitosan weight ratio of 4:1. The water-soluble derivative is a chelating agent suitable for treatment of osteogenis or other applications involving chelation. (C) 2007 Elsevier Ltd. All rights reserved.