A GHK Cu face serum appears blue because the active ingredient, GHK Cu ( copper peptide), is naturally a blue colored powder, meaning its inherent color transfers to the serum when mixed in; this blue hue Wholesale Skin Care Raw Materials Copper Peptide GHK Cu Powder GHK Cu Factory and Supplier Guangyuan Are GHK Cu Injections Safe Enough? Alternatives Options Neurogan Health Glow Peptide Injection: Revolutionizing Skin Rejuvenation Hubmed The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline