PHG · REV 2026.10 For laboratory research use only. Not medical or dosing guidance.
Peptide Handling Guide Storage, handling and documentation for research peptides
Document
CS-GHKCU
Type
Compound handling sheet
Revised
Sources checked
Bands
−20 °C

GHK-Cu (Copper Tripeptide) Handling Sheet

Also known as Copper peptide, glycyl-L-histidyl-L-lysine copper complex, prezatide copper

A tripeptide complexed with copper(II). The metal changes the handling rules: avoid chelating agents and reducing agents, protect from light, and expect a blue colour.

2 min read

Identity

Sequence
GHK
Formula
C14H24N6O4 (GHK free peptide)
Molecular weight
340.4 g/mol (GHK free peptide); the copper complex and salts weigh more
Usual supplied form
Blue lyophilized powder (copper complex), or colourless GHK peptide
Record
PubChem

Formula and weight are for the free peptide. Salt forms (acetate, TFA) weigh more; use the figure on the lot's COA.

Storage & sensitivity

Lyophilized−20 °C
In solution−20 °C
Oxidation
Moderate
Light
Moderate
Moisture
Moderate
Partly documented

Some compound data exists; the rest follows general peptide chemistry.

Bench card

  • Keep away from EDTA, citrate and other chelators, which can strip the copper.
  • Avoid reducing agents such as DTT and ascorbate, which change the copper's oxidation state.
  • Copper can catalyze oxidation; use clean tools and fresh, high-purity water.
  • Protect from light, especially in solution.
  • A colour change away from blue suggests the complex has changed.

Handling-relevant features

FeatureWhy it matters for handling
Copper(II) complexBinds through the Gly amine, His imidazole and backbone nitrogens; competing chelators can remove it
His2Copper-binding site; histidine is also susceptible to metal-catalyzed oxidation
Lys3Basic side chain; the free peptide is positively charged at neutral pH
Very short sequenceLittle aggregation risk; adsorption is low compared with longer hydrophobic peptides

What it is

GHK (glycyl-histidyl-lysine) is a tripeptide first isolated from human plasma by Pickart and colleagues, who described its high affinity for copper(II). GHK-Cu is the copper complex. It is used widely in cell and cosmetic-science research, and Pickart’s later reviews summarize that literature.

The metal matters

A copper complex behaves differently from a plain peptide:

  • Chelators such as EDTA or citrate in buffers can compete for the copper and strip it from the peptide.
  • Reducing agents such as DTT, β-mercaptoethanol or ascorbate can reduce Cu(II) to Cu(I), changing the complex and generating reactive oxygen species.
  • Redox chemistry: copper ions catalyze oxidation reactions, as reviewed by Stadtman, so oxidation of His and other components is possible even in the dry state if moisture is present.
  • Colour: the complex is blue. Loss of colour or a shift towards green or brown is worth investigating.

Storage

Form Recommended Notes
Sealed powder −20 °C Desiccant; opaque box
Solution, days 2–8 °C Amber tube; no chelators or reducing agents in the buffer
Solution, longer −20 °C Single-use aliquots

Analytical notes

Mass spectrometry may show the free peptide (about 340 Da) and copper-containing species, depending on conditions, since the complex can partly dissociate during analysis. The COA should state whether purity refers to the peptide or the complex, and whether copper content was measured.

References

  1. Pickart L, Freedman JH, Loker WJ, et al. Growth-modulating plasma tripeptide may function by facilitating copper uptake into cells. Nature. 1980;288(5792):715–717. DOI
  2. Pickart L, Vasquez-Soltero JM, Margolina A. GHK peptide as a natural modulator of multiple cellular pathways in skin regeneration. Biomed Res Int. 2015;2015:648108. DOI
  3. Pickart L, Margolina A. Regenerative and protective actions of the GHK-Cu peptide in the light of the new gene data. Int J Mol Sci. 2018;19(7):1987. DOI
  4. Stadtman ER. Oxidation of free amino acids and amino acid residues in proteins by radiolysis and by metal-catalyzed reactions. Annu Rev Biochem. 1993;62:797–821. DOI
  5. Kerwin BA, Remmele RL Jr. Protect from light: photodegradation and protein biologics. J Pharm Sci. 2007;96(6):1468–1479. DOI

This sheet covers laboratory storage and handling of research material only. It does not describe use in humans or animals, and the supplier's datasheet for your lot takes priority.