Cyclic Voltammetry-An Electrochemical Approach to Study Metal-based Potential Antitumor Drug-DNA Interaction

The application of electrochemical measurements of the redox couples of metal-based antitumor potential drugs in the presence of DNA is a highly sensitive method due to the resemblance between the electrochemical and biological reactions. CV provides a useful complement to the other biophysical methods of investigations such as UV-visible spectroscopy and fluorescence studies. Since the redox active metal complexes are not amenable to such methods either due to weak absorption bands viz; forbidden d-d transitions or because of overlap of electronic transitions with those of DNA molecule, they can potentially be studied via voltammetric techniques. Equilibrium constant (K) for the interaction of the metal complexes with DNA can be obtained from shifts in peak potentials, and the number of base pair sites involved in binding through intercalative, electrostatic or hydrophobic interactions can be obtained from the dependence of current passed during oxidation or reduction of the bound species on the amount of added DNA. In this review, we primarily focus on the description of the DNA interaction with some potential metalbased antitumor drugs as investigated by cyclic voltammetry. In our laboratory, we have employed CV studies to validate the binding strength of a series of potential metal- based drugs with CT-DNA.