DIELECTRIC-PROPERTIES OF BAT COLLAGEN IN THE TEMPERATURE-RANGE OF THERMAL-DENATURATION

The measurements of dielectric properties of collagen BAT in the solid state were made over a frequency of the electric field range of 10 Hz to 10 kHz and at temperatures from 298 to 503 K. The temperature dependence of the dielectric constant epsilon' and the dielectric loss factor epsilon'' of collagen show that thermal denaturation involves two stages. The first one corresponds to the removal of loosely bound water. The second stage is related to the release of structural bound water and probably to the beginning of the thermal transition from triple helix to coil. The observed frequency dependence of the constants epsilon' and epsilon'' may be due to Maxwell-Wagner-Sillars polarization and a lesser degree to dipolar polarization of water molecules. The method of time-temperature superposition was used to calculate the energy of activation from dielectric date of collagen.