Fluorescence dynamics of interactions between polyamide PyPyPy beta Dp and DNA

The photophysical properties of the polyamide PyPyPy beta Dp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluorescence spectroscopy. It was found that the excited-state properties of PIPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased intensity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 32 ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.Chemistry, MultidisciplinarySCI(E)EI0ARTICLE175-804