... -Pro-Gly-NH2Quality standard1,Appearance: white powder2,Water content (Karl Fischer): ≤8%3,Acetate content (HPLC method): ≤10%4,Amino acid composition ... %7,Total impurity (by two HPLC methods): ≤2%8,Peptide content (Kjeldahl method): ≥80%9,Assay (anhydrous, without acetate): 95%-105 ...