Description
PrymaLab · Research Use Only
GHK-Cu 100MG Copper Peptide
Glycyl-L-histidyl-L-lysine copper(II) · CAS 89030-95-5 · 100mg lyophilized
GHK-Cu 100mg is a lyophilized vial of the copper(II) complex of glycyl-L-histidyl-L-lysine, CAS 89030-95-5, molecular weight 401.91. The tripeptide was first isolated from human plasma by Pickart and Thaler in 1973 and binds copper(II) with high affinity through its histidine imidazole and terminal amine groups.
Specification Table
| Property | Value |
|---|---|
| Compound | GHK-Cu |
| Systematic name | Glycyl-L-histidyl-L-lysine copper(II) complex |
| Alternative designations | Copper tripeptide-1, prezatide copper, Cu-GHK |
| CAS number, copper complex | 89030-95-5 |
| CAS number, free peptide | 49557-75-7 |
| Molecular formula | C14H22CuN6O4 |
| Molecular weight | 401.91 g/mol |
| Amino acid sequence | Gly-His-Lys |
| Residue count | 3 |
| Metal centre | Copper(II), Cu2+ |
| Coordination sites | Histidine imidazole nitrogen, terminal amine, backbone amide nitrogen |
| First isolation | Human plasma, Pickart and Thaler, 1973 |
| Reported active range | 10-12 to 10-9 M in dermal fibroblast collagen assay |
| Vial content | 100 mg lyophilized powder |
| Appearance | Blue to blue-violet lyophilized cake |
| Purity | Per lot-specific certificate of analysis |
| Solubility | Water soluble. Compatible with bacteriostatic and sterile water |
| Buffer incompatibility | Chelating agents including EDTA compete for copper(II) and disrupt the complex |
| Storage, lyophilized | -20°C, protected from light and moisture |
| Storage, reconstituted | 2-8°C, protected from light |
| Photosensitivity | Copper(II) complexes are light-sensitive. Amber vials or foil recommended |
| Regulatory status | No approved human or veterinary formulation in any jurisdiction |
Why Does the Copper Matter?
The peptide and the complex are different molecules with different registry numbers, and treating them as interchangeable is the commonest error in this area.
Free GHK is a three-residue peptide, CAS 49557-75-7. GHK-Cu is that peptide with a copper(II) ion coordinated to it, CAS 89030-95-5. Coordination occurs through the imidazole nitrogen of the histidine side chain, the terminal amine of the glycine, and a deprotonated backbone amide nitrogen. The geometry is square planar, and the findinging complex is thermodynamically stable enough that GHK is considered a physiological copper carrier.
Maquart and colleagues demonstrated why this distinction has functional weight. In their fibroblast collagen assay, a control tripeptide, L-glutamyl-L-histidyl-L-proline, was inactive under identical conditions (Maquart et al., FEBS Letters, 1988). Had the activity been a simple copper-delivery effect, any copper-binding tripeptide should have reproduced it. None did.
That finding points at sequence-specific recognition rather than metal supply, and it is the reason a copper salt cannot substitute for the complex in an experiment.
What Did the Original Fibroblast Work Measure?
The Maquart study remains the most concretely quantified piece of GHK-Cu pharmacology, and its numbers are worth stating precisely rather than paraphrasing.
Cultured dermal fibroblasts were exposed to GHK-Cu across a concentration range spanning 10-12 to 10-9 M. Collagen synthesis increased across that range with maximal activity near 10-9 M. Cell number did not change, which matters because it separates increased synthesis per cell from simple proliferation.
Picomolar activity is unusual and worth pausing on. Most small molecules require micromolar concentrations to produce measurable cell responses. Activity three to six orders of magnitude below that suggests a receptor-mediated or high-affinity mechanism rather than a bulk chemical effect, and it also means that carryover contamination between experiments is a realistic risk in a laboratory working with this compound.
What Does the Gene Expression Data Show?
Pickart and Margolina reviewed transcriptomic data indicating that GHK modulates a broad set of human genes (Pickart and Margolina, International Journal of Molecular Sciences, 2018). The breadth is the notable part rather than any single pathway.
Reported categories include collagen and glycosaminoglycan synthesis, antioxidant response elements, and the balance between matrix metalloproteinases and their tissue inhibitors. That last pair is worth understanding: metalloproteinases degrade extracellular matrix while their inhibitors restrain them, so a compound shifting the ratio changes net matrix turnover without necessarily changing synthesis alone.
A caution belongs alongside this. Broad transcriptomic modulation is easy to over-read. A compound that shifts expression of many genes is not necessarily doing something coordinated, and gene-level changes do not automatically translate to protein-level or tissue-level changes. The 2018 review is a synthesis of expression data, not a demonstration of coordinated physiological effect.
When Would GHK-Cu 100mg Be the Right Vial Size?
Choosing GHK-Cu 100mg is a study-design decision rather than a value question, and 100mg is a substantial quantity for a compound active at picomolar concentrations.
The arithmetic makes the point. One hundred milligrams is roughly 249 micromoles. Reconstituted into 10 ml, that gives a 24.9 mM stock. Reaching a 1 nM working concentration from there requires roughly a 25-million-fold dilution, which in practice means serial dilution across several steps rather than a single transfer.
That is manageable, and it is also where error accumulates. Each dilution step carries pipetting error, and errors compound multiplicatively across a serial dilution. For work at the low end of the reported active range, a smaller vial reconstituted to a lower stock concentration reduces the number of steps and therefore the accumulated error.
The 100mg format suits laboratories running many experiments from one lot, where lot-to-lot consistency matters more than dilution convenience, or work at higher concentrations where fewer steps are needed.
How Is the Complex Confirmed and Preserved?
Visual inspection does more work here than with most peptides. The blue to blue-violet colour comes directly from d-d electronic transitions in the copper(II) centre, so colour is a first-order indicator that the complex is intact. A colourless or faded preparation has lost its copper.
Ultraviolet-visible spectroscopy formalises the same observation. Copper(II) peptide complexes show a characteristic absorbance band in the visible region, and its position and intensity report on the coordination environment. A shifted band suggests a changed coordination geometry, which may follow from pH change or competing ligands.
Buffer choice is the practical trap. EDTA and other chelating agents bind copper(II) with higher affinity than the tripeptide does and will strip the metal, leaving free GHK and a copper-EDTA complex. Phosphate buffers can also precipitate copper at some concentrations. Check buffer composition before use rather than after an inexplicable null finding.
How Does GHK-Cu 100mg Fit Alongside the Other Formats?
Three GHK-Cu presentations exist in this catalogue and they are not interchangeable in practice, even though the compound is identical across all of them.
The 100mg vial is the bulk format. Its case rests on lot continuity: one synthesis batch supplying an extended programme removes batch-to-batch variation in purity profile, counterion content and copper stoichiometry as a confounding variable. Across three separate 50mg vials from different lots that variation is present whether anyone measures it or not.
The 50mg vial suits work where the dilution arithmetic matters more than continuity, since a smaller quantity reconstituted into the same volume gives a lower stock and therefore fewer serial steps to reach picomolar working concentrations.
The preloaded pen removes reconstitution entirely and fixes concentration at manufacture, which trades flexibility for consistency across draws.
For a laboratory running a defined programme over months, the 100mg vial plus disciplined aliquoting is usually the strongest combination. Reconstitute once, divide immediately, freeze the divisions, and thaw each only once. That approach captures the lot-continuity advantage without leaving a large volume of copper-containing solution sitting through the whole study.
Reconstitution and Storage in Laboratory Practice
Add diluent slowly against the vial wall and swirl gently until the cake dissolves. Avoid shaking. At 100mg the reconstitution volume sets the stock concentration for every downstream dilution, so decide it before opening the vial and record it immediately.
Light protection is not optional for this compound. Copper(II) complexes are photosensitive and copper can participate in redox chemistry generating reactive oxygen species under illumination. Amber vials, foil wrapping, or storage in the dark are all standard practice, and the choice should be recorded alongside the other preparation details.
Hold lyophilized material at -20°C away from light and moisture. Reconstituted solution goes to 2-8°C, shielded from light, aliquoted before freezing. Discard any solution that has lost its colour, developed cloudiness, or shows particulate matter, and log the observation rather than simply replacing the vial.
Published Literature
Each entry below was confirmed against the publisher record or a primary index. The 1973 Nature New Biology paper is the original isolation report and remains worth reading for context.
- Maquart FX, Pickart L, Laurent M, Gillery P, Monboisse JC, Borel JP. FEBS Letters. 1988;238(2):343-346. DOI: 10.1016/0014-5793(88)80509-X
- Pickart L, Margolina A. International Journal of Molecular Sciences. 2018;19(7):1987. PMID: 29986520
- Pickart L, Vasquez-Soltero JM, Margolina A. BioMed Research International. 2015;2015:648108.
- Pickart L, Thaler MM. Nature New Biology. 1973;243(124):85-87.
- Siméon A, Emonard H, Hornebeck W, Maquart FX. Life Sciences. 2000;67(18):2257-2265.
Frequently Asked Questions
What is GHK-Cu 100mg?
GHK-Cu 100mg is a lyophilized vial containing the copper(II) complex of glycyl-L-histidyl-L-lysine, CAS 89030-95-5, molecular weight 401.91. The tripeptide was first isolated from human plasma in 1973. Supplied for laboratory research use only and not approved for human or veterinary use in any jurisdiction.
Is GHK the same as GHK-Cu?
No, and they carry separate registry numbers. Free GHK is the three-residue peptide, CAS 49557-75-7. GHK-Cu is that peptide with a copper(II) ion coordinated through the histidine imidazole, the terminal amine and a backbone amide nitrogen. The complex behaves differently from the free peptide in published assays.
Why is the powder blue?
The colour arises from d-d electronic transitions in the copper(II) centre, which makes it a first-order indicator that the complex is intact. A colourless or noticeably faded preparation has lost its copper. Ultraviolet-visible spectroscopy formalises the same observation through the position and intensity of the visible absorbance band.
What concentrations were used in the original research?
Maquart and colleagues reported collagen synthesis in cultured dermal fibroblasts across 10 to the minus 12 through 10 to the minus 9 molar, with maximal activity near 1 nanomolar and no change in cell number. Picomolar activity is unusual and suggests high-affinity recognition rather than a bulk chemical effect.
Can a copper salt substitute for GHK-Cu?
Published data argues against it. In the original fibroblast work a control tripeptide, L-glutamyl-L-histidyl-L-proline, was inactive under identical conditions. Had activity been a simple copper-delivery effect, any copper-binding tripeptide should have reproduced it. The finding points to sequence-specific recognition rather than metal supply.
Which buffers should be avoided?
Anything containing EDTA or another chelating agent, because these bind copper(II) more tightly than the tripeptide does and will strip the metal, leaving free GHK and a copper-chelator complex. Phosphate buffers can also precipitate copper at some concentrations. Check composition before use rather than after an unexplained null finding.
How much bacteriostatic water should be used for 100mg?
That depends entirely on the target stock concentration, which should be decided before the vial is opened. One hundred milligrams is roughly 249 micromoles, so reconstitution into 10 ml gives approximately a 24.9 millimolar stock. Reaching 1 nanomolar from there requires serial dilution rather than a single transfer.
Why does serial dilution introduce error here?
Because pipetting error compounds multiplicatively across steps, and reaching picomolar working concentrations from a millimolar stock requires several. For work at the low end of the reported active range, a smaller vial reconstituted to a lower stock concentration reduces the step count and therefore the accumulated uncertainty.
What does the gene expression literature actually show?
A 2018 review reported that GHK modulates a broad set of human genes spanning collagen and glycosaminoglycan synthesis, antioxidant response, and the balance between matrix metalloproteinases and their tissue inhibitors. Breadth of transcriptomic modulation is easy to over-read, and gene-level change does not automatically translate to tissue-level effect.
How should the vial be stored?
Lyophilized at minus 20 Celsius, protected from light and moisture. Reconstituted at 2 to 8 Celsius, shielded from light, aliquoted before freezing. Light protection matters more for this compound than most, since copper(II) complexes are photosensitive and copper can drive redox chemistry under illumination.
When is the 100mg format preferable to the 50mg?
When a programme runs across months and lot continuity matters more than dilution convenience. One synthesis batch removes batch-to-batch variation in purity profile, counterion content and copper stoichiometry as a confounder. Three separate 50mg vials from different lots carry that variation whether or not anyone measures it.
How should a large vial be divided?
Reconstitute once, aliquot immediately, freeze the aliquots and thaw each only once. That captures the lot-continuity advantage without leaving a large volume of copper-containing solution standing through an entire study, which is the failure mode a bulk vial otherwise invites.
Does copper stoichiometry vary between lots?
It can, and standard peptide purity figures will not reveal it. A preparation at 0.7 copper per peptide is different material from one at 1.0, and only elemental analysis by atomic absorption or inductively coupled plasma methods establishes which you have.
Compliance Statement
GHK-Cu 100mg is sold exclusively for laboratory research use. It is not a drug, food, or cosmetic product, and it is not a dietary product of any kind. It is not approved by the FDA or any comparable authority for human or veterinary use. This product is not intended to diagnose, treat, cure, or prevent any disease. It must not be given to humans or animals. Purchase is restricted to qualified researchers and institutions operating within applicable laws. All handling is the responsibility of the purchasing laboratory.
Other formats of GHK-CU
GHK-CU is also stocked as GHK-Cu Nasal Spray, GHK-CU 50mg/ml preloaded 3ml pen and GHK-CU 50MG. Each listing states its own quantity and concentration, and the pen and vial comparison explains what changes between formats.
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