Keratincovered

Keratincovered is a term used to describe an object, surface, or tissue that is covered with keratin, a family of fibrous structural proteins. Keratin-covered tissues owe their durability and protective properties to keratin, which is produced by specialized epidermal cells and becomes a tough, cross-linked outer layer through keratinization. In vertebrates, keratin occurs in different forms: alpha-keratin in mammals, which makes up hair, nails, and the outer skin layer; beta-keratin in birds and reptiles, forming feathers, claws, beaks, and scales.

Keratincovered surfaces can be natural, such as human skin or nails and bird feathers, or artificial, when keratin-based coatings are applied to materials to enhance biocompatibility, wear resistance, or barrier properties. In practical contexts, keratin coatings and films have been explored for wound care, dental and orthopedic implants, and protective coatings on various substrates, where the keratin layer serves as a protective or bioactive interface.

Properties and limitations: Keratin is relatively insoluble, resistant to proteolysis, and can be crosslinked by disulfide bonds, contributing to stiffness and resilience. Limitations include potential brittleness under certain conditions, sensitivity to heat and aggressive solvents, and variability depending on keratin source and processing methods.

Sourcing and sustainability: Keratin materials are commonly derived from animal byproducts such as feathers, wool, and hair. Research also examines recombinant or plant-based alternatives to address environmental and ethical considerations.

See also: Keratin, Keratinization, Biomaterial coatings.