Physical and chemical properties of freeze-dried amnio-chorion membranes sterilized by γ irradiation

Physical and chemical properties of freeze-dried amnio-chorion membranes sterilized by γ-irradiation. Investigation on physical and chemical properties of freeze-dried amnio-chorion membrane as well as the total number of bacteria contained were done on irradiated and unirradiated membranes. Parameters observed to evaluate the membranes were tensile strength, water vapour transmission rate, Aw, infrared spectra and total bacterial count before irradiation. These membranes will be used as biological burn dressing. The effects of storage time up to 1 month at room temperatures, i.e. 29 +- 20C on mechanical properties of freeze-dried membranes were also done. No significant change could be observed on physical and chemical properties of radiation sterilized membranes compared to unirradiated ones (p. 0.1). To protect the physical properties of freeze-dried membranes it is suggested that the membranes be processed as quickly as possible after delivery. (author). 10 figs, 7 refs