DNA binding and DNA cleavage studies of a water soluble cobalt(II) complex containing dinitrogen Schiff base ligand: The effect of metal on the mode of binding

Binding interaction of a water soluble cobalt(II) complex of a Schiff base, SF, (SF = N,N′-bis{5-[(triphenylphosphonium chloride)-methyl] salicylidine}- o-phenylenediamine) with calf thymus DNA (CT-DNA) has been investigated. The intrinsic binding constant ( K b = 5 × 10 4 M −1) was determined. In comparison with previous study the results indicate that the binding affinity of SF is stronger than its Co(II) complex. Multi-spectroscopic experiments reveal that the binding modes of Co(II) complex in comparison with SF are different; SF may be intercalating between DNA base pairs while its Co(II) complex most likely interact with DNA in an electrostatic binding mode. Binding interaction of water soluble cobalt(II) complex containing Schiff base ligand, SF, with calf thymus DNA (CT-DNA) has been investigated and the result were compared with the SF. [Display omitted]