Radiation-sterilized insoluble collagenous bone matrix is a functional carrier of osteogenin for bone induction.

The influence of gamma radiation on the role of the collagenous substratum as a carrier for proteins which cause bone induction was examined. Osteoinductive demineralized bone matrix was extracted by 4 M guanidinium hydrochloride. The insoluble collagenous bone matrix (ICBM) obtained was not osteoinductive; however, when reconstituted with partially purified osteogenin, bone induction was restored. In order to apply the principle of bone induction to clinical use, methods of sterilization must be optimized to maintain the osteoinductive activity of bone allografts. The inactive substratum was irradiated and reconstituted with an active, partially purified bone extract and bioassayed. Irradiation of the ICBM by a Cobalt 60 source at a dose of 1 and 3 Mrads had no deleterious effect on the functional role of the substratum.