Review: Interactions of Metal Ions With Nucleic Acids and Their Subunits. An Electrochemical Approach

Different electrochemical methods (differential pulse polarography, sweep voltammetry, alternating current voltammetry, chronocoulometry, cyclic voltammetry) can be used to investigate the interactions of metal ions such as osmium tetroxide, platinum complexes, Cu(II), Ni(II), Zn(II), Cd(II), Pb(II) and Eu(III) with DNA, t-RNA and their subunits. Modern electrochemical methods can detect very small perturbations in a double-helical structure as well as the behavior of single stranded (denatured) fragments of nucleic acids. The effectiveness of polarographic methods is comparable to enzymatic techniques which use specific nucleases. The polarographic data can also be used for the quantitative evaluation of the metal ion nucleic acid interactions (e.g., to calculate the association or stability constants and the number of binding sites). Some topics concerning these problems as well as general aspects of metal-nucleic acid interactions are discussed in this review.