STUDY OF THE MOLECULAR MOBILITY OF COLLAGEN

The dielectric relaxations of a biopolymer, collagen, have been studie d by means of the thermally stimulated current (TSC) technique. To inv estigate effects of water on TSC spectra, complementary measurements b y differential scanning calorimetry (DSC) have been performed. In dehy drated collagen, three spectral bands were recorded in the temperature range of -180-60 degrees C, labelled alpha, beta(1), and gamma in the order of decreasing temperature. The TSC spectrum of hydrated collage n exhibits a supplementary band labelled beta(2). By using the fractio nal polarization method, the gamma and beta(1) modes have been attribu ted to localized movements of nonpolar (apolar) sequences and polar se quences, respectively. The alpha mode has been associated with delocal ized movements of the collagen macromolecules. Finally the beta(2) mod e has been attributed to reorientations of bound water molecules insid e the collagen fibers. (C) 1995 John Wiley & Sons, Inc.