... (CAS NO. 73049-73-7) Solubility : Soluble in waterThe product is water soluble polypeptide formed by degradation of silk protein (fibroin ... (protein collagen, bone glue protein, gelatin proteins, etc), silk peptide is nutrient-rich but can be easily absorbed by hair. Skin ... peptide whose molecular weight ranges between 500 and 2,000, is better at making membrane, the membrane has nice luster, feels well ...