A novel injectable collagen matrix: In vitro characterization and in vivo evaluation

We present here a unique engineered collagen formulation that is injectable and compacts into a porous viscoelastic solid after implantation, achievin g completely focal application without cross-linking. This implant provides a cohesive continuously porous matrix, as demonstrated by permeability and compression experiments. Those experiments also provide initial mechanical characterization of the material and establish the ability to modify, thes e essential properties by design. Further, the short-term compaction and lo ng-term stability of the implant in vivo in terms of both physical and hist ological responses are assessed in an animal model to demonstrate the mecha nism of action and long-term persistence of this novel material.