DTPA and its two derivatives were synthesized and used as catalysts in DNA cleavage. Under physiological conditions, a series of experiments have been done. The effects of DNA cleavage with three ligands were studied under different concentrations, cleavage time, and pH values. The results strongly suggested that the plasrnid DNA （pUC 19） can be cleaved efficiently by CITC- DTPA. For the cleavage reaction catalyzed by CITC-DTPA, Form I DNA could convert to Form II mostly, and the DNA-cleavage mechanism involved an oxidative pathway. 2009 Chuan Qin Xia. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
