Fibrous Scaffolds for Tissue Engineering Electrospun from Fibroin-Containing Solutions

The stiffness of scaffolds serving as substrates for growing cells and living tissues can be increased by using silk fiber to reinforce biopolymers. Biopolymer scaffolds for tissue engineering and regenerative medicine can be produced via electrospinning of fibrous materials from solutions of preliminarily degummed silk fibroin. The properties of fibroin solutions in the presence of nonsolvents and crosslinking agents, the influence of EtOH on the conformational transition in fibroin solutions, and the conditions for spinning fibers from compositions based on silk fibroin and chitosan were studied. Two methods for converting fibrous materials made of fibroin into a water-insoluble form were proposed, i.e., structural rearrangements on going to the β-sheet conformation and chemical crosslinking by the natural reagent genipin. Water-insoluble ultrathin fibers made of fibroin, the morphology of which was confirmed by atomic force microscopy, were obtained and shown to be effective when used as scaffolds for tissue engineering.