Khakl O. Metal ions effect on DNA structural transitions in aqueous solutions containing alcohols and urea

The objects of study: DNA complexes with Cu2+ and Са2+ ions in aqueous and mixed solutions containing ethanol, 1,2-propanediol, glycerol and urea. The aim of the study is to investigate the DNA structural transitions under Cu2+ and Са2+ ions action in solution, and to determine the influence of dielectric permeability, solution structure, temperature on DNA structural transitions. Methods and equipment are IR spectroscopy, light scattering, SHF-dielectrometry. Results, novelty: it is shown that on DNA interaction with Cu2+ and Ca2+ ions in aqueous and mixed solutions DNA transits into the compact state. The measure of sizes of compact particles is obtained, the compactisation model is proposed. DNA compactisation dependencies on the counter-ions valence and hydration, the temperature and content of solvents are studied. It is stated that in mixed solutions DNA compactisation depends not only on the solution dielectric permeability but on the solution structure. The fields of application are molecula r biophysics, cryobiology.