Electrical conductivity of aqueous solutions of high-polymeric DNA with LiCl salt

The structure of DNA solutions with LiCl salt was investigated through electrical conductivity experiments conducted across various temperatures. The results show that the presence of DNA markedly reduces the conductivity of LiCl solutions, revealing three characteristic concentration ranges: in the first range (0–0.3 M), the conductivity of the DNA-containing solution increases more slowly than that of the pure LiCl solution; in the second range (0.3–0.9 M), both systems exhibit nearly the same rate of conductivity increase; and in the third range (above 0.9 M), the conductivity of the DNA solution grows much more slowly than that of the salt solution without DNA. These effects are qualitatively explained by a developed model, which attributes them to the ordering of ions induced by the macromolecule, which constrains their motion and limits their contribution to charge transport. The findings indicate potential applications in DNA-based technologies, particularly in the development of electrolyte batteries. • Electrical conductivity of DNA-LiCl system was studied for concentration (0.0 – 1.0 M) and temperature (25 – 65 °C) ranges. • DNA reduces LiCl conductivity, showing three regimes: 0–0.3 M weak rise; 0.3–0.9 M similar rates; >0.9 M strongly suppressed. • The results are explained by the ordering of ions around DNA, restricting their motion and reducing charge transport.