UV-vis studies on the interaction of Zn(II) complex of propranolol drug with ct-DNA

The investigations of interaction of metal complexes containing drugs as a ligand with DNA is very exciting and significant, not only in understanding the mechanism of interaction, but also for the design of new drugs [1]. In the present work, we studied the interaction of Zn(II) complex containing propranolol drug with ct-DNA. Electronic absorption spectroscopy is an effective technique to study the interaction between drug molecules and ct-DNA by monitoring possible changes in absorption intensity and position of the bands [2]. The changes in UV–vis absorption of above complex in the absence and presence of ct-DNA were examined (Fig. 1) in the Tris–HCl buffer solution (pH=7.4). Upon the increasing of the concentration of ct-DNA, the absorption band of above Zn(II) complex at 289 nm was influenced, resulting in hypochromicity and indicated that there is an attractive interaction between them. The value of intrinsic binding constant (Kb=4×104 M-1) indicates that the Zn(II) complex binds to the ct-DNA with a high affinity.