Interaction studies between a 1,10-phenanthroline adduct of palladium(II) dithiocarbamate anti-tumor complex and calf thymus DNA. A synthesis spectral and in-vitro study

The interaction of calf thymus DNA (CT-DNA) with a novel synthesized and characterized Palladium (II) complex with the formula of [Pd (Et-dtc) (phen)] NO3 (where phen is 1,10-phenanthroline and Et-dtc is ethyldithiocarbamate) was extensively studied by various spectroscopic techniques. UV-vis studies imply that there is a set of 6 binding sites for the complex on DNA with positive cooperativity in the binding process. This complex unexpectedly denatures the DNA at very low concentration (similar to 9.8 mu M). Gel filtration studies indicate that the binding of metal complex with DNA is strong enough not to readily break. Fluorescence studies show that the palladium complex intercalates in DNA through the planar 1,10-phenanthroline ligand presented in its structure. Several binding and thermodynamic parameters are also described. Furthermore, anti-tumor studies of this water soluble complex against human cell tumor lines (K562) have been done. It shows 50% cytotoxic concentration (Ic(50)) value much lower than that of cisplatin. (c) 2010 Elsevier B.V. All rights reserved.