GHK Cu: The Peptide That Supports Healthy Aging GHK Cu (copper peptide) is naturally occurring in the body and plays a role in supporting skin health, collagen production, and tissue repair. As GHK CU (50mg) Nordsci Copper Peptides Serum for Face 2% GHK CU & 4% EGF Seraphime Intense Copper Binding GHK Cu 5% +Palmitoyl Oligopeptide 0.3% Repair S Chebo Clinic Theoretical study of copper binding to GHK peptide ScienceDirect