We are offering collagen. Cas no: 9064-67-9 mf: c4h6n2o3r2.(c7h9n2o2r)n packing detail: 25kg carton content: protein: 90% ash: 2.0% water insoluble: 0.1% arsenic: 1.0 mg kg physical character: usage: a water-soluble protein, enzyme-catalyzed gelatin products. uses:collagen is widely used in food, medicine, daily chemical industry, textile, printing and dyeing, paper making, chemical industry