A voltammetric study on drug-DNA interactions: Kinetic and thermodynamic aspects of the relations between the anticancer agent dasatinib and ds-DNA using a pencil lead graphite electrode

The interaction of anticancer drug dasatinib (DSB) with double-stranded calf thymus DNA (ds-DNA) was investigated by using voltammetric techniques on a single-use pencil graphite electrode (PGE). Free DSB displayed a single oxidation peak in acetate buffer solution (pH 4.80). The changes in the anodic CV and DPV peak currents of DSB were investigated in the absence and presence of DNA in aqueous media. Some kinetic parameters, such as diffusion coefficient (D), heterogeneous rate constants (k(s)), and electrode surface concentration (Gamma) of free DSB and DSB-DNA complex, were calculated using CV data. The DSB-DNA complex formation constant (K) and Gibbs free energy (Delta G degrees) were determined to be 2.51x10(4) M-1 and 25.10 kJ mol(-1), respectively. The results obtained show that there is an interaction between DSB and ds-DNA, and DSB binds to DNA through intercalation interaction. The formation equilibrium constant (K) was found to compare well with similar data reported in the literature. Besides, the thermodynamic parameters (K and Delta G degrees) obtained by voltammetric measurements were compared with UV spectroscopic data and were found to be approximately of the same order (4.49x10(4) M-1).