The effect of γ-radiation on soluble and insoluble collagens

The effect of γ-radiation on soluble and insoluble collagens was studied by the modifications in the electron microscopical appearance, X-ray diffraction pattern, optical birefringence, thermal stability and the tensile properties of collagen fibres obtained from rat- and kangaroo-tail tendons. The γ-ray dosages used were 10 and 30 Mrad. At 10 Mrad collagen fibrils from rat-tail tendon did not show any change in the electron microscope while those from kangaroo-tail tendon showed partial disorder or disappearance of the cross-striations and exhibited twisting. At 30 Mrad, the latter fibrils appeared gelatinised while rat-tail-tendon fibrils retained the fibril form but without the cross-striations. These results are in conformity with the corresponding X-ray diffraction patterns and the data on the optical birefringence and thermal and mechanical stability of these fibrils, and point to the possibility that soluble collagen is more resistant to γ-radiation than insoluble collagen