On the physico-chemical and dielectric properties of glutaraldehyde crosslinked galactomannan–collagen films

The effects of galactomannan, a plant polysaccharide widely distributed in nature, on the physicochemical properties of collagen films, were studied using infrared spectroscopy, dielectric spectroscopy, thermal analysis (DSC), swelling and scanning electron microscopy, with possible applications in biomedical, cosmetic and food industry. Infrared bands typical for collagen molecules (amide I, II and III) and galactomannan structure, present in the spectrum of films with 50% of galactomannan, showed that the gum was retained in the collagen fibers. The integrity of the triple helical structure of collagen was conserved in the mixture. The resulting films crosslinked with increasing amounts of glutaraldehyde (GA), when analysed by differential scanning calorimetry (DSC), showed that the reaction induced the presence of two structures, which were the result of the heterogeneous reaction of GA. The presence of galactomannan in the collagen films, increased the swelling, and this effect was inconsistent with GA increments. Scanning electron microscopy showed the entanglement of the galactomannan by fibers of collagen. The piezoelectric strain tensor element d14, the elastic constant s55, and the dielectric permittivity ε11 as obtained for the galactomannan–collagen film were studied. Resonance measurement of the piezoelectric strain constant d14 of galactomannan–collagen film (60%) gives 0.081 pC/N.