Your copper peptide product should be this exact blue. If it isn't, you already have your answer. GHK Cu is blue because of coordination chemistry, not dye. The Cu ion at the center 14 Glutathione Benefits for Your Body and Health Annex Naturopathic Clinic Skin Perfection GHK Cu Copper Peptide Serum Booster, 1 Percent Blue Liquid For Face, Neck, Body, Hair, And Scalp, 0.5 oz Walmart.com Glutathione Uses, Benefits, Side Effects And Medicines Close up of Blue Copper Peptides GHK Cu in Pipette. Beauty serum for anti aging beauty routine Stock Photo Alamy