Interactions between heterometallic bridged cis-or trans-Pt(II)-Zn(II)complexes and calf thymus DNA

Abstract

More recently scientific attention is paid on non platinum based drug especially on bio essential metal ions Design of the heterometallic complexes is possible way to overcome limitation of platinum based drugs T he four novel complexes cis PtCl (NH 3 μ 4 4 bipyridyl) ZnCl terpy )}](ClO 4 2 trans PtCl (NH 3 μ 4 4 bipyridyl) ZnCl terpy )}](ClO 4 2 cis PtCl (NH 3 μ pyrazine) ZnCl terpy )}](ClO 4 2 and trans PtCl (NH 3 μ pyrazine) ZnCl terpy )}](ClO 4 2 (where terpy 2 2 6 2 terpyridine) were synthesized and characterized The binding of the heterometallic bridged cis or trans Pt(II) Zn(II) complexes to calf thymus DNA (CT DNA) was studied using UV absorption and fluorescence emission spectroscopy The results indicate that the complexes bind strongly to DNA K b in the order of 10 4 M 1 through groove binding, hydrogen bonds, and hydrophobic or electrostatic interaction According to Stern Volmer quenching constant K SV and binding constant (K the cis PtCl (NH 3 μ 4 4 bipyridyl) ZnCl terpy )}](ClO 4 2 complex interacts with CT DNA EB more strongly than the rest of the studied complexes.