Human recombinant collagen can be cross-linked with a variety of chemical cross-linking agents. Cross-linking methods can be tuned to confer collagen-based scaffolds with specific physical properties, improved antigenicity and thermal stability without impeding the ability of the material to integrate into the surrounding tissue and to promote regeneration. Here, we describe a method to cross-link human recombinant collagen using a water soluble carbodiimide. Carbodiimides are referred to as zero-length cross-linking agents as they are not incorporated into the final cross-link and thus pose minimal risk with respect to cytotoxicity. The resulting collagen-based scaffold possesses properties comparable to that of the human cornea and is thus suitable for use as a corneal substitute.