KPV GHK Cu (10 50 MG) Sigma Compounds GHK Cu Copper Peptide: Dosage, Before and After Results, and How It Works Perfect B 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 Buy GHK Cu Exceptional 99%+ Purity Third Party COA Included