Fabrication of nanofibers using fibroin regenerated by recycling waste silk selvage

Abstract

An effective process of recycling silk selvage to fabricate fibroin-containing nanofibers was demonstrated. Sericin and fibroin were extracted from the silk waste, and fibroin was successfully separated from the mixture. Thus, the proposed process of regeneration of useful components from silk selvage waste was effective and beneficial. We further investigated the use of the regenerated fibroin to fabricate highly functional nanofibers via electrospinning. The electrospinning solvent systems and processing conditions, such as voltage, tip-to-collector distance, and flow rate, were intensively studied. The selection of proper solvent was important to control the morphology and quality of the resultant nanofibers. Fibroin nanofibers fabricated using formic acid exhibited highly controlled uniformity. Additionally, composite PVA/fibroin nanofibers were successfully fabricated from the regenerated fibroin. Our studies highlight the potential of silk selvage, which is not a waste product but a valuable material, and it can be recycled via the proposed process to yield functional nanofiber materials suitable for cutting-edge nano/biotechnological applications owing to their biocompatibility.