Biomimetic Enzyme Entrapment Strategies

Silks are fibrous proteins produced by insects or spiders, and provide structural and protective functions.  Silkworm silk from Bombyx mori is one of the most characterized silks and consists of the heavy and light chains that form fibers with impressive mechanical strength. Aqueous processing conditions, biocompatibility, and biodegradability of silk fibroin, along with facile chemical modifications, are attractive features of silk that have led its exploitation for a variety of medical and non-medical applications. More recently, renewed emphasis has been place on silk fibroin as a matrix for the entrapment of enzymes. We will present our studies on the entrapment of enzymes using silk, and describe how the unique structure of silk fibroin protein creates an environment that is conducive to the stabilization of entrapped proteins. The water-insoluble films maintain the activity of the entrapped enzymes under a variety of temperature, pH and storage conditions. Silk is robust and malleable, thus increasing the range of processing possibilities. Silk was also used to modify paper substrates for the immobilization of enzymes for paper-based analytical devices. Based on our and other studies, silk is an intriguing material for the immobilization of biomolecules and expands the possibilities for generating multifunctional materials.