Effect of Gamma-irradiation Sterilization on the Antibacterial Efficacy and the Properties of a Hybrid Burn Dressing

A new bio restorable hybrid burn dressing which combines a synthetic porous top layer with a spongy collagen sub layer was developed and studied. The top layer contained the antibiotic drug gentamicin for controlled release to the wound site. Our investigation focused on the effects of gamma-irradiation sterilization (10, 25, 35 and 50 kGy) on the antibacterial efficacy and on the mechanical and physical properties of this wound dressing. The gentamicin release profile from the hybrid wound dressing was very effective against three relevant bacterial strains, Staphylococcusalbus, S. aureus and Pseudomonas aeruginosa, for at least 14 days. This effectiveness did not decrease after gamma-irradiation sterilization, even at high irradiation doses. The changes in the mechanical properties, which were probably due to a combination of cross linking and chain scission of the hybrid layers by the gamma radiation, are beneficial when the radiation doses are in the range of 10-35 kGy.