Material scientists admire spider silk for being lightweight and strong. Now another arthropod product is getting into the act—insect cuticle, the tough, flexible material in the insect exoskeleton.
Researchers at Harvard’s Wyss Institute for Biologically Inspired Engineering analyzed insect cuticle, which includes chitin and other proteins, such as the fibroin also found in spider silk. They then devised a method to produce a material made up of layers of chitin and fibroin. The result is on par with an aluminum alloy for strength, but at half the metal’s weight.
They call the stuff “shrilk” - a combination of shrimp, as discarded shrimp shells are a good source of chitin, and silk. Its flexibility can be manipulated by adjusting the water content – just as insects do. The research is in the journal Advanced Materials. [Javier G. Fernandez and Donald E. Ingber, Unexpected Strength and Toughness in Chitosan-Fibroin Laminates Inspired by Insect Cuticle]
Shrilk’s creators say it could be a green alternative to plastic, for trash bags and even diapers. Its strength and biocompatibility could make it good for surgical suture or as scaffolding for tissue regeneration.
Shrilk is a clear film. If it can be made to stay clear when thick, it could make Enterprise Engineer Montgomery Scott’s transparent aluminum obsolete. In advance.
—Cynthia Graber
