Fecha de publicación: -- Fuente: WIPO "tomato" Described herein is a method of preparing processed silk fibroin which can include providing silk yarn harvested from a silk producer, the silk yarn including silk fibers containing silk fibroin and sericin, and degumming the silk yarn in greater than 0.3 to 0.5 M sodium carbonate at a temperature of about 80 to about 90° C., and for a time of 60 to 480 minutes, to provide degummed silk fibers having a sericin concentration of 0-0.5 wt %. The method can also include dissolving the degummed silk fibers in a chaotropic agent, diluting the dissolved silk fibers, and performing tangential flow filtration (TFF) on the diluted or clarified silk fiber solution using a regenerated cellulose filter, and concentrating and recovering processed silk fibroin from the TFF.