Preparation of chitosan–copper complexes and their antitumor activity

Copper complexes of chitosan have been synthesized. Complexes with different copper to chitosan ratios were tested in vitro as potential antitumor agents with 293 cells and HeLa cells. At the ratio of 0.11 mol copper per one chitosan residue, the complex exhibited a higher antitumor activity and less toxicity than other copper–chitosan complexes tested. In addition, this study showed that copper–chitosan complex inhibited tumor cell proliferation by arresting the cell cycle progression at the S phase in 293 cells.