Table of Contents
Metal-Based Drugs
Volume 2008, Article ID 275084, 8 pages
Research Article

DNA Binding and Photocleavage Studies of Cobalt(III) Ethylenediamine Pyridine Complexes: [Co(en)2(py)2]3+ and [Co(en)2(mepy)2]3+

1Department of chemistry, Faculty of Science, Osmania University, Hyderabad, Andhra Pradesh 500 007, India
2Indian Institute of Chemical Technology, Taranaka, Hyderabad 500 007, India

Received 7 May 2007; Accepted 4 July 2007

Academic Editor: Jannie C. Swarts

Copyright © 2008 Penumaka Nagababu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Two novel cobalt(III) pyridine complexes (1)[Co(en)2(py)2]3+ and (2)[Co(en)2(mepy)2]3+ (en=ethylenediamine, py=pyridine, and mepy=methylpyridine) have been synthesized and characterized. The interaction of these complexes with calf thymus DNA was investigated by absorption, emission spectroscopy, viscosity measurements, DNA melting, and DNA photocleavage. Results suggest that the two complexes bind to DNA via groove mode and complex 2 binds more strongly to CT DNA than complex 1. Moreover, these Co(III) complexes have been found to promote the photocleavage of plasmid DNA pBR322 under irradiation at 365 nm, cytotoxicity results of complexes are also showing anticancer activity.