Abstract: We synthesized and characterized a new complex of Cu₂(L-Arg)₂(SSA)(H₂O)₂ (L-Arg=L-Arginine, SSA=5sulfosalicylic acid), and studied interaction between complex and DNA by electrochemical method, spectroscopic method and viscosity method with herring sperm DNA as bimolecular target. The  results show that when the scanning rate is 0.1 V/s, a pair of obvious redox peaks appear at 0.124 8,-0.518 9 V,  the redox peak current of the complex increases with the scanning rate, and the reaction of complex at glassy carbon electrodes is controlled by diffusion process. After adding DNA, the oxidation and reduction peak currents of the complex decrease, the formal potential increases, the peak position of the complex shifts,  the absorption intensity decreases, which is positively related to the concentration of DNA, and the relative viscosity of the complex increases. Therefore, there is intercalation between complex and DNA.

Key words: L-Arg, 5sulfosalicylic acid, copper (Ⅱ), herring sperm DNA