Improving biomechanical performance of irradiated biological material

Compositions, and methods of making, at least one irradiated, sterilized and biomechanically strengthened biological material are described. The biological materials are treated with at least one substance that has a high affinity for free radicals. The biological materials have a molecular or supramolecular level of porosity which allows for the penetration of molecules of the high affinity free radical scavenging substance into the biological materials.