Electrical Conductivity of Fish Skin Collagen in the Temperature Range 290-380 K

Collagen is the major biopolymer of a living organism, which physical properties depend on water content. The observed transmission of spongiform encephalophaties (BSE) to humans resulted in the development of new sources of collagen. Fish skin seems to be one of such safe sources of collagen. Measurements of electrical conductivity as a function of temperature provides information, among other things, on the water release process. Experiment was carried out for fish skin (FSC) collagen (type I) and bovine Achilles tendon collagen (type I). Each sample was heated two times. Current-voltage characteristic was determined for FSC collagen to determine the range, within which the relation is linear. The primary differences appeared to be in electric conductivity, which was higher for FSC collagen than for BAT collagen. Electric conductivity varied from 10^{-6} S/m to 10^{-10} S/m depending on material and temperature. The process of free and bound water release was manifested as a peak on electrical conductivity-temperature curve between 320-350 K. The activation energy of the charge conduction process, determined on the basis of the Arrhenius plot, was material dependent and considerably higher for FSC collagen.