A Thermodynamic Study of New Designed Complex of Ethylendiamine 8-Hydroxyquinolinato Palladium(II) Chloride with Calf Thymus DNA

Abstract

A Thermodynamic study on the interaction of bovine calf thymus DNA with new designed Pd(II) complex (Ethylendiamine- 8-hydroxyquinolinato Palladium(II) chloride) was studied by using isothermal titration calorimetry (ITC) at 27 <TEX>${^{\circ}C}$</TEX> in Tris buffer solution at pH = 7.5. The enthalpies of Pd(II) complex + DNA interaction are reported and analysed in terms of the new solvation theory. It was indicated that there are three identical and non-cooperative sites for Pd(II) complex. The binding of a Pd(II) complex is endothermic with association equilibrium constants of 428.03 m<TEX>$M^{-1}$</TEX> at 27 <TEX>${^{\circ}C}$</TEX>. The binding of Pd(II) complex can cause some changes in the stability of the DNA at low and high Pd(II) complex concentrations. Our results suggested that this complex might interact with DNA as an intercalator, thus interfering with DNA replication and cell proliferation.