GHK-Cu Peptide

Reference

GHK vs GHK-Cu

GHK and GHK-Cu compared on composition, mass, copper complexation, research settings, evidence maturity and regulatory context, with sources.

By the GHK-Cu Peptide editorial team · Last reviewed · Editorial review: pending

Short answer

GHK is the tripeptide glycyl-histidyl-lysine (340.38 g/mol) [PubChem]; GHK-Cu is the same peptide with copper(II) bound through three nitrogen atoms [Hureau 2011], recorded at 402.92 g/mol for the 1:1 complex [PubChem]. They are different chemical entities, and findings for one are not findings for the other.

GHK vs GHK-Cu comparison

Choose a dimension. Every cell is sourced; the reference list is at the end of the page.

Not interchangeable. Findings for one form, formulation or route of exposure do not transfer to another. A result from a topical cream, a cell culture or an implanted wound chamber says nothing about a different product or route.

GHK compared with GHK-Cu
DimensionGHK (copper-free)GHK-Cu (copper complex)
Chemical compositionGlycine–histidine–lysine tripeptide, no metal [PubChem]The same tripeptide with one copper(II) ion (1:1); a 2:1 complex with two peptides per copper also exists [PubChem]
Formula and massC14H24N6O4, 340.38 g/mol [PubChem]C14H23CuN6O4⁺, 402.92 g/mol as recorded for prezatide copper [PubChem]
Registered namesPrezatide · UNII 39TG2H631E · CAS 49557-75-7 [FDA GSRS]Prezatide copper · UNII 6BJQ43T1I9 · CAS 89030-95-5 [FDA GSRS]
Copper complexationFree amine, imidazole and lysine groups with measured acid–base constants [Rabenstein 1977]; can take up copper(II) from solutionCopper(II) bound by the glycine amine, the deprotonated Gly–His amide and a histidine imidazole [Hureau 2011]; conditional Kd 7.0 × 10⁻¹⁴ M at pH 7.4 [Trapaidze 2012]
Molecular propertiesVery hydrophilic (computed XLogP3 −4.4); lysine amine protonated at physiological pH [Conato 2001]Charged complex; a dimer in the crystal and a monomer in solution [Hureau 2011]
Investigated research settingsKeratinocytes and skin equivalents [Choi 2012], carbonyl-quenching chemistry [Beretta 2007], one hair trial as a 5-ALA complex [Lee 2016], rat plasma kinetics [Endo 1997]Fibroblast and matrix studies [Siméon 2000], permeation through excised skin, animal wound models, and topical human trials [Miller 2006]
Evidence maturity (this database)7 primary records; 0 randomised human trials46 primary records; 3 randomised human trials, all topical: two null on objective measures [Bishop 1992] [Miller 2006], one reporting faster ulcer closure [Mulder 1994]
Attribution problemCopper-free results can change once copper is present in the mediumAn MMP-2 effect seen with GHK-Cu was reproduced by copper ions alone, not by GHK alone [Siméon 2000], so copper itself can explain some results
Regulatory context (US)Not an approved drug [openFDA]; used in cosmetics as tripeptide-1Not an approved drug [openFDA]; injectable routes in FDA Category 2 for compounding [FDA 2026]; cosmetic name copper tripeptide-1
Safety limitationsNo human safety study of copper-free GHK by any non-topical route is indexed; rats cleared it rapidly to His-Lys after intravenous dosing [Endo 1997]Keratinocyte irritation markers unchanged at the tested concentrations [Li 2016]; FDA cites immunogenicity risk and limited human data for injectable use [FDA 2026]; clinical evidence called sparse in 2026 [Mateescu 2026]

Why the distinction matters for reading studies

Studies use GHK-Cu, copper-free GHK, palmitoylated or conjugated derivatives, and multi-ingredient products under overlapping names. The evidence explorer tags every record with the substance actually tested, so the two can be filtered apart. Copper itself is biologically active: in one fibroblast study copper ions alone reproduced an effect attributed to the complex [Siméon 2000], which is why well-designed studies include copper-only controls.

See also molecular structure and how to tell the two apart analytically.

Frequently asked questions

What is the difference between GHK and GHK-Cu?

GHK is the tripeptide glycyl-histidyl-lysine on its own. GHK-Cu is the same peptide with a copper(II) ion bound through three of its nitrogen atoms, which changes its mass, charge, colour and chemistry.

Is “GHK basic” the same as GHK?

“GHK basic” is not a registered name; it is a retail label for copper-free GHK. The registered name for copper-free GHK is prezatide; the copper complex is prezatide copper.

Do GHK and GHK-Cu give the same results in studies?

Not necessarily. In one fibroblast study, an effect seen with GHK-Cu was reproduced by copper ions alone but not by GHK alone. Results for one form cannot be assumed for the other.

References

  1. Rabenstein DL, Greenberg MS, Evans CA (1977). Determination of the microscopic and macroscopic acid dissociation constants of glycyl-L-histidyl-L-lysine and related histidine peptides. Biochemistry. PubMed 14668 · doi:10.1021/bi00624a026[Chemistry, grade D]
  2. Hureau C, Eury H, Guillot R et al. (2011). X-ray and solution structures of Cu(II) GHK and Cu(II) DAHK complexes: influence on their redox properties. Chemistry. PubMed 21780203 · doi:10.1002/chem.201100751[Chemistry, grade D]
  3. Trapaidze A, Hureau C, Bal W et al. (2012). Thermodynamic study of Cu2+ binding to the DAHK and GHK peptides by isothermal titration calorimetry (ITC) with the weaker competitor glycine. J Biol Inorg Chem. PubMed 21898044 · doi:10.1007/s00775-011-0824-5[Chemistry, grade D]
  4. Conato C, Gavioli R, Guerrini R et al. (2001). Copper complexes of glycyl-histidyl-lysine and two of its synthetic analogues: chemical behaviour and biological activity. Biochim Biophys Acta. PubMed 11325542 · doi:10.1016/s0304-4165(01)00127-1[Chemistry, grade D]
  5. Siméon A, Emonard H, Hornebeck W et al. (2000). The tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+ stimulates matrix metalloproteinase-2 expression by fibroblast cultures. Life Sci. PubMed 11045606 · doi:10.1016/s0024-3205(00)00803-1[In vitro, grade D]
  6. Choi HR, Kang YA, Ryoo SJ et al. (2012). Stem cell recovering effect of copper-free GHK in skin. J Pept Sci. PubMed 23019153 · doi:10.1002/psc.2455[In vitro, grade D]
  7. Lee WJ, Sim HB, Jang YH et al. (2016). Efficacy of a Complex of 5-Aminolevulinic Acid and Glycyl-Histidyl-Lysine Peptide on Hair Growth. Ann Dermatol. PubMed 27489425 · doi:10.5021/ad.2016.28.4.438[Human, grade B]
  8. Beretta G, Artali R, Regazzoni L et al. (2007). Glycyl-histidyl-lysine (GHK) is a quencher of alpha,beta-4-hydroxy-trans-2-nonenal: a comparison with carnosine. insights into the mechanism of reaction by electrospray ionization mass spectrometry, 1H NMR, and computational techniques. Chem Res Toxicol. PubMed 17672515 · doi:10.1021/tx700185s[Chemistry, grade D]
  9. Miller TR, Wagner JD, Baack BR et al. (2006). Effects of topical copper tripeptide complex on CO2 laser-resurfaced skin. Arch Facial Plast Surg. PubMed 16847171 · doi:10.1001/archfaci.8.4.252[Human, grade A]
  10. Bishop JB, Phillips LG, Mustoe TA et al. (1992). A prospective randomized evaluator-blinded trial of two potential wound healing agents for the treatment of venous stasis ulcers. J Vasc Surg. PubMed 1495150 · doi:10.1067/mva.1992.37086[Human, grade A]
  11. Mulder GD, Patt LM, Sanders L et al. (1994). Enhanced healing of ulcers in patients with diabetes by topical treatment with glycyl-l-histidyl-l-lysine copper. Wound Repair Regen. PubMed 17147644 · doi:10.1046/j.1524-475X.1994.20406.x[Human, grade A]
  12. Endo T, Miyagi M, Ujiie A (1997). Simultaneous determination of glycyl-L-histidyl-L-lysine and its metabolite, L-histidyl-L-lysine, in rat plasma by high-performance liquid chromatography with post-column derivatization. J Chromatogr B Biomed Sci Appl. PubMed 9187381 · doi:10.1016/s0378-4347(96)00460-4[Chemistry, grade D]
  13. Li H, Toh PZ, Tan JY et al. (2016). Selected Biomarkers Revealed Potential Skin Toxicity Caused by Certain Copper Compounds. Sci Rep. PubMed 27892491 · doi:10.1038/srep37664[In vitro, grade D]
  14. Mateescu DM, Gavrilescu DM, Mincioaga RI et al. (2026). GHK-Cu as a Bioactive Metallopeptide and Drug-Delivery Cargo: Coordination Chemistry, Formulation Science, Therapeutic Evidence, and a Translational Roadmap. Pharmaceutics. PubMed 42797253 · doi:10.3390/pharmaceutics18091077[Review, grade R]
  15. PubChem, National Library of Medicine. glycyl-L-histidyl-L-lysine (CID 73587). Source[retrieved 2026-11-11]
  16. PubChem, National Library of Medicine. Prezatide copper (CID 71587328). Source[retrieved 2026-11-11]
  17. PubChem, National Library of Medicine. Bisprezatide copper (CID 9831891). Source[retrieved 2026-11-11]
  18. FDA Global Substance Registration System. PREZATIDE, UNII 39TG2H631E. Source[retrieved 2026-11-11]
  19. FDA Global Substance Registration System. PREZATIDE COPPER, UNII 6BJQ43T1I9. Source[retrieved 2026-11-11]
  20. U.S. Food and Drug Administration (2026-04-22). Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Source[retrieved 2026-11-11]
  21. U.S. Food and Drug Administration, openFDA. openFDA Drugs@FDA and NDC directory queries for prezatide, copper tripeptide and GHK. Source[retrieved 2026-11-11]