Effects of carbodiimide crosslinking conditions on the physical propertiesof laminated intestinal submucosa

Functional tissue engineering of load-bearing repair tissues requires the d esign and production of biomaterials that provide a remodelable scaffold fo r host infiltration and tissue regeneration while maintaining the repair fu nction throughout the remodeling process. Layered constructs have been fabr icated from chemically and mechanically cleaned porcine intestinal collagen using ethyl-3(3dimethylamino) propyl carbodiimide (EDC) and an acetone sol vent. By varying the concentration of the crosslinker from 1 to 10 mM and t he solvent from 0 to 90% acetone, the strength, stiffness, maximum strain, thermal stability, lamination strength, and suture retention strength can b e adjusted. These parameters have either functional importance or the poten tial to modify the remodeling kinetics, or they have both. This study inves tigates the interdependence of these parameters, the specific effects that variations in concentration can achieve, and how the two crosslinking varia bles interact. The results demonstrate that there is substantial latitude i n the design of these constructs by these straightforward crosslinking modi fications. These data provide the basis for studying the in vivo response t o crosslinking conditions that will supply the requisite strength while sti ll allowing host cell infiltration and remodeling. (C) 2001 John Wiley & So ns, Inc.