Molecular Structure Explorer
GHK
Structure of the compound covered in this guide.
Last reviewed: October 2026 · Cleared Peptides research team
Research use only. GHK (Basic Tripeptide): Research Guide is supplied for laboratory research. It is not a drug, food, cosmetic, or dietary supplement. It is not FDA-approved. It is not for human or veterinary administration. This page does not give a dose or a method of administration. A study cited on this page describes that study’s own test article. It does not make this lot an approved medicine. To check a fact, open the PubMed or DOI link, confirm the authors and year, and match the paper’s compound name, CAS number, or sequence to the specification table. The full method is on the research desk page. Identity and purity for a lot are only what that lot’s certificate of analysis reports. An HPLC percentage is not a sterility result and not an endotoxin result unless the certificate prints those tests.
GHK-Basic is the copper-free tripeptide glycyl-L-histidyl-L-lysine. It is the same three-residue sequence as the peptide portion of GHK-Cu, supplied without a copper ion. The copper complex is a different registry entry and is described on the GHK-Cu guide.
Identifiers
| Name | GHK (basic tripeptide) |
|---|---|
| Synonyms | Glycyl-L-histidyl-L-lysine; tripeptide-1, copper-free form |
| CAS number | 49557-75-7 |
| PubChem CID | 73587 |
| Molecular formula | C14H24N6O4 |
| Molecular weight | 340.4 g/mol |
| Sequence | Gly-His-Lys |
| Copper | Not present. GHK-Cu, the copper(II) complex, is CAS 89030-95-5. |
| Physical form | Lyophilized powder |
| Solubility | Depends on salt form and solvent. Use the lot COA. No single public solubility figure is stated here. |
Published laboratory notes
Published coordination studies describe GHK as a histidine-containing tripeptide that can bind copper(II) when copper is added in a laboratory mixture. This catalog item is the metal-free peptide, so a laboratory controls whether copper is present. The copper complex has a different molecular formula (C14H22CuN6O4) and a different CAS number.
These notes are structural and chemical. They are not statements of benefit or use.
Research material
GHK (basic tripeptide) · GHK-Cu · COA page
Other names
| This catalog item | GHK-Basic. The copper-free tripeptide. |
|---|---|
| Sequence name | Glycyl-L-histidyl-L-lysine; Gly-His-Lys |
| Other labels | GHK; tripeptide-1 in the copper-free form |
| Not this item | GHK-Cu, the copper(II) complex, CAS 89030-95-5. That complex is a different registry entry. |
GHK-Basic compared with GHK-Cu
Both names refer to the same three residues, Gly-His-Lys. The difference is the metal. GHK-Basic is supplied without copper. Published coordination studies start from that metal-free peptide and add Cu(II) in the experiment. Lau and Sarkar measured that binding by potentiometry and visible absorption. A later EPR study reported three nitrogen ligands to the copper ion. Those are coordination results. They are not statements of benefit or use.
| GHK-Basic | GHK-Cu | |
|---|---|---|
| Sequence | Gly-His-Lys | Gly-His-Lys |
| Copper | Not present | Copper(II) |
| CAS | 49557-75-7 | 89030-95-5 |
| Formula | C14H24N6O4 | C14H22CuN6O4 |
The copper complex is written up on the GHK-Cu guide.
Analytical testing notes for GHK (basic tripeptide)
GHK (basic tripeptide) is identified in this guide as CAS 49557-75-7, formula C14H24N6O4, listed mass 340.4 g/mol. The sequence recorded here is Gly-His-Lys. An identity test compares a measurement with those values. A mass spectrum is the usual measurement for a peptide. FTIR, when a certificate uses it, is a supporting infrared fingerprint and is less specific for closely related sequences.
GHK (basic tripeptide) is a short peptide. Short, polar sequences retain weakly on C18 unless the mobile phase contains an ion-pairing acid such as trifluoroacetic acid. Detection is usually ultraviolet at 214 nm, because many of these sequences have no tryptophan or tyrosine and are nearly silent at 280 nm. Mass spectrometry, and MS/MS when isomers are plausible, is what distinguishes one short sequence from another with a similar retention time.
HPLC purity for this material is an area-percent result at the wavelength and gradient the laboratory states, commonly ultraviolet detection near 214 nm on a reversed-phase column. The instrument is a gradient pump, injector, column oven, and UV or diode-array detector. That percentage is not the number of milligrams in the vial. Water, acetate, trifluoroacetate, and other UV-silent material can dominate the gross weight while the purity figure stays high. Net peptide content, from an assay or amino-acid analysis, is the separate result to read when the certificate reports it.
A sterility test and an endotoxin test are not included in a chemical purity result. The compendial sterility test is a culture method (USP <71>): membrane filtration or direct inoculation into fluid thioglycollate medium and soybean-casein digest medium, incubated for 14 days. A PCR sterility screen uses a thermal cycler to detect microbial DNA and is a different method. The endotoxin test (USP <85> LAL, or USP <86> recombinant Factor C) reports endotoxin units with an incubating reader or a cartridge reader. Use a result only when that method is printed on the lot certificate. One published example in this catalog states that the report does not cover microbial contamination or endotoxins. The full description of equipment, standards, and how US laboratory accreditation works is in peptide analytical testing. Lot records are on the COA page.
Frequently Asked Questions
Is GHK-Basic the same vial as GHK-Cu?
No. GHK-Basic is the copper-free tripeptide, CAS 49557-75-7. GHK-Cu is the copper(II) complex, CAS 89030-95-5.
What does tripeptide-1 mean here?
It is another name for the Gly-His-Lys sequence. On this page it means the copper-free form.
Is GHK-Basic for human use?
No. It is supplied for laboratory research use only and is not for human or veterinary use.
Selected References
Peer-reviewed literature listed as scientific background for laboratory researchers. Citation does not imply endorsement by the authors, and it is not a statement of benefit or use.
- Pickart L, Thaler MM. Tripeptide in human serum which prolongs survival of normal liver cells and stimulates growth in neoplastic liver. Nat New Biol. 1973;243(124):85-87. Structural and biochemical identification of the Gly-His-Lys tripeptide. PubChem 73587
- Lau SJ, Sarkar B. The interaction of copper(II) and glycyl-L-histidyl-L-lysine, a growth-modulating tripeptide from plasma. Biochem J. 1981;199(3):649-656. Cited here for the potentiometric and visible-absorption study of Cu(II) binding to Gly-His-Lys, not for any use claim in the paper title. PubMed 7340824 · DOI
- Laussac JP, Haran R, Sarkar B. N.m.r. and e.p.r. investigation of the interaction of copper(II) and glycyl-L-histidyl-L-lysine, a growth-modulating tripeptide from plasma. Biochem J. 1983;209(2):533-539. Cited here for EPR evidence that Cu(II) coordinates three nitrogen atoms of the tripeptide. PubMed 6303307 · DOI
Research Use Only Notice
This guide is provided for educational and laboratory reference purposes. It summarizes published structural and biochemical literature. It does not describe, recommend, or imply any use in humans or animals. Products sold by Cleared Peptides are for laboratory research use only. They are not drugs, foods, cosmetics, or dietary supplements, are not FDA-approved, and are not intended to diagnose, treat, cure, mitigate, or prevent any disease. No dosing, administration, or use instructions are provided.
