Mechanisms of the interaction between Pr(DNR)(3) and herring-sperm DNA

Research on the interaction mechanism of drugs with DNA is essential to understand their pharmacokinetics. The interaction between rare earth complexes Pr(DNR)(3) and herring-sperm DNA was studied in Tris-HCl buffer solution (pH 7.4) by absorption and fluorescence spectroscopy and viscosity measurements. The results showed that the modes of interaction between Pr(DNR)(3) and herring-sperm DNA were electrostatic and intercalation. The binding ratio was n(Pr(DNA)3): n(DNA) = 5:1 and the binding constant was K-circle minus(292 K) = 4.34x10(3) L mol(-1). Furthermore, according to the double reciprocal method and the thermodynamic equation, the intercalative interaction was cooperatively driven by an enthalpy effect and an entropy effect