Keratin-based matrices from wool fibers and human hair

Keratin refers to a group of insoluble proteins produced by certain epithelial cells of vertebrates, belonging to the superfamily of the intermediate filament proteins, and forming the bulk of the skin and the epidermal appendages, such as wool, hairs, nails, horns, and feathers. Keratin-based materials are tough and resistant to the natural environment and to many chemicals. Keratins are naturally biocompatible and possess cell motif-binding residues supporting cellular attachment, which is the first step in the tissue engineering replacement process. Keratins for biomedical applications have been extracted, processed, and regenerated into various forms, such as films, sponges, hydrogels, fibers, nanoparticles, microcapsules, alone or blended with other natural and manmade polymers or with bioglasses. Recent literature reports on keratin-based material have been studied for different biomedical purposes, in particular for wound healing, peripheral nerve regeneration, bone reconstruction, and drug controlled release.