Synthesis of new heterometallic macromolecules: Their DNA binding, cleavage activity and in vitro model electrochemotherapy study

The homodinuclear C16H30N8O5Sn2Cl4 (1), heterotetranuclear C16H38N8O9Sn2Cu2Cl8 (2) and C16H38N8O9Sn2Mn2Cl8 (3) macrocyclic complexes were synthesized and characterized by elemental analysis, spectroscopic techniques and molar conductance measurements. The interaction studies of 1–3 with calf thymus DNA (CT-DNA) were carried out by UV–vis titration, fluorescence, cyclic voltammetry and viscosity measurements. These results were further authenticated by carrying out interaction studies of 1–3 with plasmid pBR322 DNA employing gel electrophoresis. To overcome the dose resistance, auto toxicity of the drugs, a model study based on electrochemotherapy (ECT) was carried out and the results were compared in the presence and in the absence of the applied electrical potential.