GHK-Cu is a copper tripeptide studied for wound repair and skin healing across five decades of research.

What the GHK-Cu literature establishes

GHK-Cu is the glycyl-L-histidyl-L-lysine copper(II) complex — a three-amino-acid peptide carrying a single copper ion, and one of the most-studied copper peptides in dermatology. In human fibroblast culture it raised collagen synthesis in a dose-dependent way, beginning between 10⁻¹² and 10⁻¹¹ M and peaking near 10⁻⁹ M, with no change in cell number ^[1]. That last detail matters: the molecule changed what cells made, not how many there were.

The sequence is not exotic. GHK occurs naturally inside the alpha-2(I) chain of type I collagen and circulates in human plasma, where it declines from roughly 200 ng/mL at age 20 to about 80 ng/mL by age 60 ^[3]. Loren Pickart first isolated it in 1973 as a plasma factor that made aged liver tissue synthesize proteins like younger tissue. Five decades on, the record spans collagen biology, GHK-Cu and wound healing, copper peptides for hair growth, and a genome-wide gene-expression signature.

This site reads that record the way a careful buyer reads a certificate of analysis — claim by claim, source by source. Where the data is strong (cell-culture collagen synthesis, liposomal wound closure), it says so plainly. Where it is thin (validated human pharmacokinetics, controlled scar-fading trials), it says that too. The 'legit' question — is a given claim sourced or marketed — is the organizing principle of every page.

What GHK Copper Peptide Is

GHK copper peptide is the copper(II) chelate of the tripeptide glycine-histidine-lysine, molecular weight 402.92 Da, CAS 89030-95-5. The copper sits in a square-planar coordination, bound through the histidine imidazole nitrogen, the glycine alpha-amino nitrogen, and the deprotonated glycine-histidine amide nitrogen, leaving the lysine side chain free. The intact complex is blue-violet in solution — that color is the copper(II) d-orbital absorption, and it is one of the field's oldest visual sourcing signals: an intact GHK copper peptide reads blue-violet, while a brown or green shift indicates oxidation or precipitation.

Most of the documented bioactivity belongs to the copper-loaded form, not the bare peptide. Across reviewed wound and skin models GHK-Cu raises collagen, elastin, VEGF, FGF-2, and matrix-remodeling enzymes while suppressing several inflammatory and oxidative signals ^[6]. The free peptide circulates and is studied for systemic and gene-level effects, but copper coordination is what reproduces the local matrix work.

GHK-Cu as a Copper-Binding Tripeptide

As a copper peptide, GHK-Cu does two jobs at once: it chaperones copper and it signals. The copper enables lysyl-oxidase-mediated cross-linking of collagen and elastin and contributes superoxide-dismutase-like antioxidant activity; the peptide scaffold directs that copper to fibroblasts, keratinocytes, and follicular cells rather than letting it react indiscriminately.

The stability of that binding is part of what makes the complex usable. GHK-Cu carries a very high copper stability constant — log K around 16.4 — far above the free peptide, which limits the release of pro-oxidant free copper ^[6]. In fibroblast culture the copper-bound form drives matrix synthesis at picomolar-to-nanomolar concentrations ^[1]; the free peptide does not reproduce the same MMP-2 stimulation. For sourcing purposes, this is why the form matters: a product or a study citing 'GHK' is not automatically citing GHK-Cu, and the two are routinely conflated.

Copper Tripeptide-1 (INCI name)

Copper Tripeptide-1 is the INCI (International Nomenclature of Cosmetic Ingredients) name for GHK-Cu — the label term you see on a copper-peptide skincare ingredient list. It is the same molecule described throughout this site: glycyl-histidyl-lysine copper(II), CAS 89030-95-5, also indexed under synonyms including prezatide copper and tripeptide-1 (copper). The INCI name is a useful sourcing anchor: a topical product naming 'Copper Tripeptide-1' is declaring GHK-Cu content, and a certificate of analysis should resolve to the same CAS number.

What the Research Reports on Copper-Peptide Activity

The reported copper-peptide benefits cluster around three documented activities. First, matrix synthesis: GHK-Cu stimulates fibroblast production of collagen, dermatan sulfate, chondroitin sulfate, and the proteoglycan decorin, and one canonical review reports increased collagen production in 70% of treated subjects versus 50% for vitamin C and 40% for retinoic acid ^[3]. Second, wound and tissue repair: across many models the molecule raises VEGF, FGF-2, and matrix proteins while chemoattracting repair cells ^[6]. Third, broad gene modulation: Connectivity Map analyses report GHK shifting expression of about 31.2% of human genes at a 50%-or-greater threshold ^[2].

These are findings, not promises. The strongest of them sit in cell culture and rodent models; the human evidence is concentrated in small topical trials. The pages that follow take each activity in turn — GHK-Cu research findings, wound and skin repair, and hair — and attach the study behind every number.