Copper Peptides Serum for Face 2% GHK CU & 4% EGF Cellular Glow Copper Peptide GHK Cu Serum for Face A Dermatologist's Take on the Copper Peptide (GHK Cu) Trend Before vs. after 3 months of GHK Cu peptide therapy smoother texture, more even tone, and skin that looks healthier overall. Small peptide, big difference GHK Cu Before and After: See Fine Lines and Wrinkles Fade Fast