A Spectroscopic Study of the Interaction Between the Bismarck Brown R-Eu(III) Complex and DNA

The interaction of the Eu(III)-BBR complex with herring sperm DNA is investigated using an acridine orange (AO) probe for UV-vis absorption spectroscopy and fluorescence spectroscopy. The results indicate that both the AO probe and the Eu(III)-BBR complex can intercalate into the base pairs of DNA. The binding constants of the Eu(III)-BBR complex with DNA are = 1.58 center dot 10(4) L/mol and = 9.35 center dot 10(4) L/mol, and the binding process is entropydriven. It is shown that the interaction modes between the Eu(III)-BBR complex and DNA include groove binding and intercalative binding. The mechanism of the interaction between the Eu(III)-BBR complex and DNA will provide an important theoretical basis for the synthesis of new drugs.