THE EFFECT OF GAMMA-IRRADIATION ON COLLAGEN MOLECULES, ISOLATED ALPHA-CHAINS, AND CROSS-LINKED NATIVE FIBERS

This study shows how collagen molecules are readily damaged by γ‐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 γ‐radiation should be tested for long term functional changees. We want to caution against the usag of the enzyme degradation assay as a universal test for all bioprosthetic derived from biological tissues. Copyright © 1990 John Wiley & Sons, Inc.