Fibrin polymer structure

In accordance with the present invention a novel fibrin polymer structure is disclosed. The novel fibrin polymer structure useful, for example, as a surgical sealant, is comprised of a plurality of discrete, droplets of polymerizing or polymerized fibrin each encapsulated by a "skin" of fibrin polymer. These fibrin-skin encapsulated droplets are applied so as to be built up one upon the other, layer by layer, to form an integral sealant structure. The cumulative effect of the encapsulating skins of those droplets which form the sealant surface is a surface skin which unexpectedly resists cell penetration but enhances cell migration across the surface. The sealant structure of the present invention can be prepared by spray delivery of fibrin polymer forming materials wherein the time required for the materials to commence polymerizing after mixing is less than or equal to the transit time of said materials from the applicator tip to the target surface.