CHAPTER 5: Collagen‐based Materials for Tissue Repair, from Bio‐inspired to Biomimetic

Fibrillar collagens are key components of the extracellular matrix conferring mechanical functionality to tissues in many animal organisms, while jointly supporting cell adhesion and migration. In vivo self‐assembly of collagens results in complex hierarchical architectures which are intimately related with their performance. Mimicking such architectures will allow us to come close to the properties of natural tissues and has been set as a turning point towards more efficient tissue repair materials. This chapter critically reviews the strategies developed so far, and the achievements related to the mimesis of the naturally occurring molecular, fibrillar or suprafibrillar levels found in collagen‐based extracellular matrices. The literature surveyed is mainly divided according to the criteria of the organizational level attained. Moreover, since the field of collagen‐based materials is intrinsically multidisciplinary, major concepts related to the organizational levels of collagen, such as fibril, hydrogel or dense collagen matrix, are reviewed to establish a common lexicon, allowing more effective understanding and exchange between the different participants in this research field.