Immobilization of factor XIII on collagen membranes.

Factor XIII from placenta was successfully grafted onto collagen membranes by the acyl-azide procedure. The transamidase activity retained on collagen membranes was determined by measuring the increase of fluorescence resulting from dansylcadaverine incorporation into casein. We studied the effect of different factors on the grafting: concentration and composition of the factor XIII preparation in the coupling solution and influence of the preactivation of factor XIII by thrombin. Stability studies have shown that the activity of factor XIII grafted on collagen membranes was almost constant over a period of 8 months. Sterilization by gamma-irradiation of factor XIII revealed a drastic loss of activity while the use of high-energized electron bombardment caused a reduced loss of activity. The potential of such a material for biomedical use is presently under investigation.