Essential GHK Cu Serum: What It Is, How It Works, and Why It Matters f Bacteriostaticwater.com Copper Tripeptide (GHK CU) Peptides at Refresh Clinic Dubai: Price GHK Cu Glow Peptide Stack for Skin Rejuvenation Jennifer R. Berman MD Defy GHK Cu (glycyl L histidyl L lysine) is a naturally occurring copper binding peptide found in human plasma. As levels decline with age, so may its support of the biological processes involved in collagen production, skin