GHK-Cu (glycyl-L-histidyl-L-lysine copper complex) is a naturally occurring copper-binding tripeptide that functions as a copper ionophore, facilitating cellular copper transport. GHK-Cu is one of the most extensively studied peptides in dermatological research, with documented effects on collagen production, fibroblast proliferation, glycosaminoglycan synthesis, antioxidant activity, and wound healing in tissue culture and animal models. The peptide is found naturally in human plasma, saliva, and urine, with concentrations declining with age. The injectable form of GHK-Cu was removed from FDA Category 2 restriction in April 2026. Research-grade GHK-Cu is typically supplied as a lyophilized blue powder (characteristic of copper peptide complexes) requiring reconstitution before use in cell culture and topical formulation studies.
Directory listing last reviewed July 2026.