GHK Cu Copper Peptide: Dosage, Before and After Results, and How It Works Perfect B The Pretty Purple Peptide with Powerful Benefits That gorgeous blue purple solution isn't just for looksit's GHK Cu, one of the most studied peptides in regenerative medicine. Here's what it can do for GHK Cu Lyophilized Powder Copper Peptide Powder GHK Cu Ghkcu Peptide 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 GHK CU Copper Peptide, Face Serum, 1 oz (30 ml)