DC conductivity and dielectric permittivity of collagen-chitosan films

In this paper we studied the physicochemical and dielectric properties of collagen-chitosan films, considering the development of new biomaterials which have potential applications in coating of cardiovascular prostheses, support for cellular growth and in systems for controlled drug delivery. The dielectric permittivity epsilon(11) were obtained for the collagen and collagen-chitosan films. Our results also show that the presence of chitosan contributes to an increase of the thermal stability of the collagen films, which is associated with the increase of the denaturation temperature of the collagen-chitosan samples compared with the collagen sample. We believe that the increase of the organization of the microscopic structure of the sample, results in an increase of the thermal stability. For the samples under study, the highest conductivity was obtained for the chitosan film compared to the pure collagen film. Around room temperature it is around 10 times bigger than pure collagen. (c) 2005 Elsevier B.V. All rights reserved.