The investigation of inclusion behavior of Solvent Violet 9 with 4-sulfonatocalix[n]arenes and its recognition to DNA.

The inclusion behavior of Solvent Violet 9 (SV9) with 4-sulfonatocalix[n]arenes (SCXn) (n=4,6,8) was investigated at various pH values by ultraviolet-visible spectroscopy. SV9 is able to form an inclusion complex with calixarenes. Different absorption behaviors were observed for the dye with the various host calixarenes. The molecular binding abilities were affected by the configuration of the calixarene cavities and the solution pH. Various experimental conditions, including calixarenes concentrations, were investigated and the results suggested that the three calixarene were most suitable for inclusion of the dye at pH=3.05. The formation constant could be calculated. The inclusion behavior of the complexes was studied in detail using nuclear magnetic resonance spectroscopy. Finally, the interactions of SV9 with Salmon testes DNA in SCXn supramolecular system were studied by UV-Vis absorption spectroscopy. The UV-Vis absorption show that the interaction of SV9 with DNA depends on the concentration ratio of SV9 to DNA and the pH values. The binding constants of inclusion complexes with DNA are calculated. It was observed that SCXn can affect the interactive mode of SV9 with DNA.