GHK Cu Copper Peptide Neck & Face Serum Cu Peptide Before and After: What to Expect for Skin and Hair 6 month GHK CU check in Main takeaway: skin transformation takes time. GHK CU peptide binds to copper and activates genes involved in wound healing, collagen synthesis, and skin remodeling. On the face, this translates GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? Squalane + Copper Peptide (GHK Cu) Rapid Plumping Serum