Picosecond fluorescence anisotropy decay in the ethidium/DNA complex

Academic Article


  • Ethidium bromide intercalated into calf thymus or salmon sperm DNA exhibits fluorescence anisotropy relaxation due to torsional motion (and, at long times, bending) of the DNA which is well described by the elastic continuum model for times greater than 0.5 ns. A fast component of amplitude 0.025 ± 0.01 and characteristic time 100 (-50, +100) ps is present at short times and is affected very weakly or not at all by solution viscosity. Such fast relaxation may be attributed to "wobbling" of the dye within a binding site, although it is not completely certain that all other possibilities have been rigorously excluded. © 1983 American Chemical Society.
  • Authors

    Published In

    Digital Object Identifier (doi)

    Author List

  • Magde D; Zappala M; Knox WH; Nordlund TM
  • Start Page

  • 3286
  • End Page

  • 3288
  • Volume

  • 87
  • Issue

  • 17