title: The effect of gamma-irradiation on collagen molecules, isolated alpha-chains, and crosslinked native fibers.
abstract: This study shows how collagen molecules are readily damaged by gamma-radiation at dosages commonly used for sterilizing biomedical products. At 1 Mrad, while the reported effectiveness of the radiation at such a low dosage to completely sterilize a material is questionable, less damage was caused to the collagen peptide backbone. Above such dosage, however, significant damage was clearly demonstrated with collagen alone and collagen in a chemically crosslinked tissue matrix. The enzyme digestion study showed that the material exposed to a very high dosage of radiation resisted degradation by pronase. However, molecular weight analysis showed a significant number of peptide bonds being cleaved by the radiation which could cause considerable changes in the long-term characteristics of the material. Therefore, tissues exposed to high dosages of gamma-radiation should be tested for long term functional changes. We want to caution against the usage of the enzyme degradation assay as a universal test for all bioprosthetic derived from biological tissues.
authors.affiliation: University of Southern California, School of Medicine, Department of Medicine and Biochemistry, Los Angeles 90007.
authors.forename: D T
authors.initials: DT
authors.lastname: Cheung
authors.forename: N
authors.initials: N
authors.lastname: Perelman
authors.forename: D
authors.initials: D
authors.lastname: Tong
authors.forename: M E
authors.initials: ME
authors.lastname: Nimni
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D001705:Bioprosthesis; D002417:Cattle; D003094:Collagen / Q000378:metabolism / Q000528:radiation effects*; D005720:Gamma Rays; D051381:Rats; D013242:Sterilization / Q000379:methods*; D013710:Tendons / Q000378:metabolism / Q000528:radiation effects*
chemical_list: D003094:Collagen