Copper Peptide (GHK Cu): Clinical Uses, Stability & Compounding Tips The difference between our Copper Peptides and GHK Cu GHK Cu is one specific copper peptide molecule great for signaling repair and collagen support. Our Copper Peptide formula goes beyond just Everyone's calling GHK Cu a miracle peptide But let's separate marketing from mechanism. GHK Cu isn't magic. It's a signal. A signal that: Supports tissue repair Modulates inflammation Enhances collagen + GHK Cu Copper Peptide Face Tonic (30 mL) Reduces Appearance of Fine Lines Supports Skin Firmness