Spectroscopic studies on the interaction of γ-cyclodextrin-daunorubicin inclusion complex with herring sperm DNA

摘要

The interaction of daunorubicin (DNR) with herring sperm DNA in cyclomaltooctaose (γ-cydodextrin, abbrev. γ-CD) supramolecular system was studied by UV-vis absorption spectroscopy, fluorescence spectroscopy and viscosity method. On the condition of physiological pH, the results indicate that DNR prefers to form the 1:1 inclusion complex with γ-CD. These results are further supported by infrared spectrometry (IR), and X-ray diffraction (XRD). An inclusion constant (if) for the formation of γ-CD-DNR inclusion complex has been evaluated to be 9412.39 Lmol~(-1) from the absorbance changes. It is observed that the interaction mode between γ-CD-DNR and DNA are a mixed binding, which contains partial intercalation and groove binding. The binding ratio of γ-CD-DNR with DNA is n_(γ-CD-DNR):n_(DNA) = 10:1, binding constant is K~Θ _(298.15 K) = 2.44 x 10~5 Lmol~(-1), enthalpy and entropy work as driven force in this action.