Silk: A Unique Family of Biopolymers

Insects produce silk fibers as a building material for structures to protect pupae during the metamorphosis, to protect eggs and Arthropods mainly for prey capture webs. Silks are produced and used alone or in combination with chitin or collagen, due to the affinity with those molecular species. Native silk firboin (SF) water solutions are obtained by diluting the content of the posterior division of the silkworm gland where SF is still separated from sericin. Regenerated SF in water is obtained from 'degummed' silk fibers by dissolving them in some organic solvents or concentrated saline solution and subsequent salt removal by dialysis. Silk proteins have found significant utility in biomedicine due to their high biocompatibility, tunable biodegradability and material format versatility. Perhaps its earliest biomaterial rendition, natural silk fibers have been employed as sutures for wound ligation for centuries.