The new macrocyclic polyamine derivatives of chitosan were synthesized by reacting epoxy-activated macrocyclic tetra-amine with the C6 hydroxyl or C2 amino group in chitosan. The obtained copolymers (CTS-OM, CTSNM) contain amino functional groups, the secondary amines, and more polar hydroxyl groups in its skeleton. Elemental analysis, infrared spectra, and solid-state C-13-NMR analysis confirmed their structures. The adsorption behavior of the macrocyclic polyamine grafted chitosan for Ag+, Pb2+, Hg2+, and Cr3+ was investigated. The experimental results showed that the two novel derivatives of chitosan have high adsorption capacity and good selectivity for some metal ions. (c) 2005 Wiley Periodicals, Inc.