Dielectric study of the interaction of DNA and water

The ways in which water molecules bind to DNA are studied with the aid of thermally stimulated depolarization current (TSDC) measurements of hydrated solid DNA samples and dilute aqueous solutions, in the temperature range of 80-300 K. The first two peaks of the recorded spectrum are interpreted on the basis of free water and loosely bound water dipole reorientation, respectively. It is shown that water sorbed up to at least 25% w/w is irrotationally bound to the DNA molecule. Additional dispersions, eliminated with the use of insulating foils, are attributed to space-charge depolarization connected to DC conductivity.<
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