Opening a bottle of GHK-Cu is surprising the first time: the powder is blue, and so is the solution. This color isn't a dye; it's copper. Here's what it indicates, what proportion of the bottle is actually copper, how to handle and store the peptide, and how not to confuse it with GHK alone or biotinyl-GHK.
GHK-Cu 50 mg – €39.90G50 bundle with equipment – €49.90
Why is GHK-Cu blue?
GHK alone is a white powder. When bound to copper(II) ions, it forms a complex that absorbs some visible light: the freeze-dried powder appears blue to blue-violet, and the reconstituted solution blue. The intensity depends on the concentration. A white or colorless "GHK-Cu" should raise doubts about the presence of copper.
How much copper is in a bottle?
Janoshik separately measured the peptide and copper. Based on our three analyses of GHK-Cu 50 mg:
| Report | Batch | GHK | Copper | Total | HPLC Purity |
|---|---|---|---|---|---|
| Report#241207 | BatchMP-777CU502 | GHK44.65 mg | Copper8.13 mg | Total52.78 mg | HPLC Purity99,781 % |
| Report#226148 | BatchMP-777CU501 | GHK42.70 mg | Copper7.74 mg | Total50.44 mg | HPLC Purity99,525 % |
| Report#223490 | BatchMP-777CU501 | GHK51.99 mg | Copper9.53 mg | Total61.52 mg | HPLC Purity99,765 % |
Copper represents approximately 15% of the mass, which corresponds to the expected ratio of one copper ion to one GHK molecule (masses of approximately 64 and 340 g/mol). A ratio that only indicates purity, without measuring the copper content, cannot be verified. To interpret these figures, seeread an HPLC analysis certificate.
Reconstruction
GHK-Cu dissolves easily inbacteriostatic waterAllow the bottle to return to room temperature before opening it. Inject the solvent slowly along the side, then gently rotate the bottle without shaking it. The complete method is described inreconstitute a lyophilized peptide. THEG50 Packgathers the bottle and the necessary equipment.
Conservation
| State | Où | Approximate duration |
|---|---|---|
| StatePowder, sealed bottle | OùRefrigerator (2 to 8 °C), away from light | Approximate durationSeveral months |
| StatePowder, long storage | OùFreezer (−20 °C) | Approximate durationBeyond a few months |
| StateSolution with bacteriostatic water | OùRefrigerator, never freezer | Approximate durationUp to 28 days |
These are the same rules as for other lyophilized peptides; they are detailed, with the example of retatrutide, inpeptide preservation.
Signs of a problem
A GHK-Cu solution should remain clear and blue. Discard it if it becomes cloudy, if a deposit appears, if the color changes significantly (green, brown) or disappears, or if the shelf life has expired.
GHK, GHK-Cu, biotinyl-GHK: do not confuse
| Name | What it is | Use |
|---|---|---|
| NameGHK | What it isThe tripeptide alone, without copper (white powder) | UseResearch |
| NameGHK-Cu (Copper Tripeptide-1) | What it isCopper(II) bound tripeptide (blue) | UseResearch; cosmetic ingredient |
| NameBiotinyl-GHK (Biotinoyl Tripeptide-1) | What it isGHK coupled with biotin, without copper | UseCosmetic ingredient for hair care |
| NameAHK-Cu | What it isAn analogue where alanine replaces glycine | UseSearch (seeGHK-Cu or AHK-Cu) |
Biotinyl-GHK is not GHK-Cu: it does not contain copper and is primarily used in hair lotions. PeptiLine does not sell it. For skin, ourGHK-Cu and SNAP-8 serumis formulated for this purpose.
Frequently Asked Questions
Why is GHK-Cu blue?
Because the copper(II) ion bound to the peptide absorbs some of the visible light. GHK alone, without copper, is white.
How much copper is contained in a vial of GHK-Cu 50 mg?
Based on our Janoshik analyses, between 7.74 and 9.53 mg of copper depending on the vial, or about 15% of the total mass, which corresponds to one copper ion per molecule of GHK.
How long does reconstituted GHK-Cu keep?
With bacteriostatic water, it can be stored for up to 28 days in the refrigerator, away from light. In powder form, it can be stored for several months in the refrigerator or freezer.
My GHK-Cu has changed color, is it still usable?
No, not if the solution becomes cloudy, if a deposit appears, or if the color changes significantly. A correct solution remains clear and blue.
Is biotinyl-GHK the same as GHK-Cu?
No. Biotinyl-GHK (Biotinoyl Tripeptide-1) is GHK coupled with biotin, without copper, used in hair care products. GHK-Cu is the tripeptide bound to copper.
- GHK-Cu Guide— copper tripeptide and what research says about it
- GHK-Cu and SNAP-8 Serum— copper peptide in cosmetics
- GHK-Cu or AHK-Cu— two copper peptides, two research avenues
- GHK-Cu blue: color and preservation— what the color indicates, reconstitution, storage, biotinyl-GHK (you are here)
- GHK-Cu 50 mg— lyophilized research vial, analyzed by Janoshik
- G50 Pack— GHK-Cu 50 mg with reconstitution materials
- Reading a certificate of analysis— understanding an HPLC report
- Certificates of analysis— the Janoshik reports from GHK-Cu (lots MP-777CU501 and MP-777CU502)
Janoshik Reports #241207, #226148, and #223490; standard laboratory practices for lyophilized peptides. PeptiLine products are intended for scientific laboratory research use only. This page does not provide medical advice, protocols, or dosage information.