Interaction study of methyl violet 2B with DNA and voltammetric determination of DNA in aqueous solutions

Differential pulse voltammetry, cyclic voltammetry, and chronocoulometry at a hanging mercury drop electrode were used for the study of the interaction of methyl violet 2B (MV) with double-stranded DNA in 0.1 mol dm(-3) acetate buffer pH 4.0. The mechanism of the electrochemical reduction of MV was also investigated, using cyclic voltammetry at a hanging mercury drop electrode. UV-Vis spectrophotometry was used for the investigation of the interaction as well. The kinetic parameters of the reduction of MV and the DNA-MV complex and the thermodynamic parameters of the formed DNA-MV complex were calculated. Moreover, the calibration dependence of the peak current of MV on the concentration of DNA in acetate buffer was constructed to be used for the indirect determination of DNA based on the decreasing peak current of MV with increasing concentration of DNA in the measured solution. [GRAPHICS] .