GHK-Cu is a copper complex of the tripeptide glycyl-L-histidyl-L-lysine, naturally present in human plasma. It is one of the most studied peptides in skin-model and gene-expression research and is supplied strictly for laboratory research use.

Why does GHK-Cu solution look blue?

The characteristic blue color comes from the copper(II) ion coordinated to the GHK peptide — the same copper-peptide complex studied in the literature. The tint is an expected physical property of the authentic complex.

What does the research literature say about GHK-Cu?

Published work spans skin-model endpoints, wound-context models, and gene-expression profiling, with reported modulation of repair- and matrix-associated gene pathways in cell-culture systems.

What purity standard applies to GHK-Cu?

PX1 specifies ≥ 99% purity by HPLC with molecular identity confirmed by LC-MS. Every batch includes a lot-specific Certificate of Analysis and endotoxin screening.

Is GHK-Cu approved for human use?

GHK-Cu supplied by PX1 Research is strictly a laboratory research compound and is not for human or veterinary administration.

Compound Monograph — PX-GHK

GHK-Cu

Copper tripeptide — glycyl-L-histidyl-L-lysine Cu(II) complex

For laboratory research use only. Not for human or veterinary use.

Compound data

Compound class: Copper-binding tripeptide complex
Structure: Glycyl-L-histidyl-L-lysine complexed with Cu(II)
Molecular formula: C14H24CuN6O4
Molar mass: ≈ 403.9 g/mol (complex)
CAS number: 49557-75-7
Natural occurrence: Endogenous in human plasma, saliva, and urine; declines with age in published data
Presentation: Lyophilized powder — 50mg and 100mg vials
Purity specification: ≥ 99% by HPLC, identity confirmed by LC-MS

Overview

GHK-Cu is a naturally occurring copper complex of the tripeptide glycyl-L-histidyl-L-lysine, first isolated from human plasma in 1973 by Loren Pickart. The tripeptide has a high affinity for copper(II) ions, and the resulting complex is the biologically studied form.

Published research places GHK-Cu among the most studied cosmetic and dermatological-model peptides, with a literature spanning skin-model endpoints, wound-context models, and gene-expression studies. A frequently cited data point in the literature is the age-related decline of endogenous GHK-Cu plasma levels.

Mechanism in the research literature

Copper delivery and enzyme cofactor context

GHK functions as a copper(II) carrier in published models. Copper is an essential cofactor for enzymes including lysyl oxidase and superoxide dismutase, both of which appear in the connective-tissue and antioxidant research contexts associated with GHK-Cu.

Gene-expression findings

Published gene-expression profiling work has reported that GHK modulates the expression of a substantial number of human genes in cell-culture models, with enrichment in matrix-remodeling and repair-associated pathways — the basis of much of its research interest.

Matrix metalloproteinase context

Published studies have examined GHK-Cu's interaction with metalloproteinase and antiproteinase expression in skin-model systems, framing its role in extracellular-matrix research.

Published research summary

Isolated from human plasma in 1973; the founding publications describe its growth-modulating activity in hepatocyte culture models.
Published gene-array studies report broad expression modulation in cultured human cells, concentrated in repair and matrix pathways.
An extensive cosmetic-formulation literature examines GHK-Cu in topical skin-model endpoints.
Every PX-GHK batch is released against ≥ 99% HPLC purity with LC-MS identity confirmation and a lot-specific Certificate of Analysis.

Handling, reconstitution & storage

Storage (lyophilized): -20 °C long term; 2–8 °C short term; protect from light
Reconstitution: Bacteriostatic water down the vial wall; the solution will present a characteristic blue tint from the Cu(II) complex
Example ratio: 50mg vial + 2.0 mL diluent = 25 mg/mL
Stability (reconstituted): Reference ≈ 28–30 days refrigerated at 2–8 °C with bacteriostatic water
Light sensitivity: Protect both lyophilized and reconstituted material from light

Frequently asked questions

Related resources

GHK-Cu research overview Glow Protocol research hub Peptide reconstitution calculator

Research use only. GHK-Cu (PX-GHK) is supplied exclusively as a laboratory research compound. It is not a drug, food, or cosmetic, and it is not intended for human or veterinary administration, diagnostic use, or household use. Statements on this page summarize published scientific literature for reference purposes and do not constitute medical advice or health claims. All PX1 Research batches ship with lot-specific Certificates of Analysis confirming ≥ 99% purity by HPLC and identity by LC-MS.