Description
GHK-Cu 50mg Refill — Product Identity and Format
The labelled mass of every GHK-Cu presentation refers to the copper-peptide complex, not the peptide component alone.
GHK-Cu 50mg Refill is a research-grade lyophilised preparation of GHK-Cu (Copper(II) glycyl-L-histidyl-L-lysine), a naturally occurring copper-binding tripeptide complex first isolated from human plasma albumin by Loren Pickart in 1973. GHK (glycyl-L-histidyl-L-lysine) is a tripeptide with the sequence Gly-His-Lys that forms a stable complex with copper(II) ions through coordination bonds involving the imidazole nitrogen of histidine and the terminal amino groups of glycine and lysine. Each vial supplied by Core Research contains lyophilised GHK-Cu, verified by RP-HPLC to a minimum purity of ≥99.0%, with molecular identity confirmed by ESI-MS.
The compound’s ability to chelate copper(II) ions and deliver them to copper-dependent enzymes — including lysyl oxidase (essential for collagen and elastin crosslinking), superoxide dismutase (SOD), and cytochrome c oxidase — is thought to underlie many of its reported biological effects in experimental systems.
Compound Identity Matrix
| Attribute | Value | Notes |
|---|---|---|
| Common Name | GHK-Cu; Copper(II) GHK; Copper Tripeptide-1 | Naturally occurring copper-binding tripeptide complex |
| Sequence | Gly-His-Lys · Cu(II) | Cu(II) coordination via His imidazole and terminal amines |
| CAS Number | 89030-95-5 | GHK-Cu copper complex; CAS 49557-75-7 is the free tripeptide GHK (distinct compound) |
| Molecular Formula | C14H23CuN6O4⁺ | Copper complex cation (PubChem CID 73981) |
| Molecular Weight | 403.91 Da | Copper complex (monoisotopic) |
| Physical Form | Blue-green lyophilised powder | Colour associated with Cu(II) coordination; not a substitute for analytical identity confirmation |
| Purity (RP-HPLC) | ≥99.0% | C18 column, UV 220 nm |
| Identity Confirmation | ESI-MS | ±0.1 Da of theoretical MW |
Analytical Specification & Release Testing
Every batch of GHK-Cu supplied by Core Research is subjected to a comprehensive analytical release protocol before dispatch. Purity is determined by RP-HPLC (C18 column, UV 220 nm) confirming ≥99.0% purity with a maximum single impurity of ≤0.5%. Molecular identity is confirmed by ESI-MS with the observed [M+H]⁺ ion matched against the theoretical mass of GHK-Cu (MW 403.91 Da) to within ±0.1 Da. Copper content is confirmed by ICP-MS to verify stoichiometric Cu(II) complexation. Endotoxin content is confirmed at <1.0 EU/mg by LAL kinetic turbidimetric assay. A batch-specific Certificate of Analysis documenting all release results is available via the CoA Portal.
| Test Parameter | Method | Release Specification |
|---|---|---|
| Purity (RP-HPLC) | C18 column, UV 220 nm | ≥99.0%; max single impurity ≤0.5% |
| Identity (ESI-MS) | Electrospray ionisation MS | ±0.1 Da of theoretical MW 403.91 Da |
| Copper Content (ICP-MS) | Inductively coupled plasma MS | Stoichiometric Cu(II) complexation confirmed |
| Endotoxin (LAL) | Kinetic turbidimetric LAL | <1.0 EU/mg (non-sterile research material) |
| Appearance | Visual inspection | Blue-green lyophilised powder |
Note: An endotoxin specification does not confer sterility. GHK-Cu 50mg is a non-sterile research reagent. Researchers requiring sterile conditions should apply appropriate filtration in accordance with their institutional SOPs. Batch-specific analytical results are available on the CoA; the specifications above are release criteria, not typical results.
Storage and Transport Conditions
| Condition | Specification | Notes |
|---|---|---|
| Long-term storage (lyophilised) | −20°C, desiccated | Store in original sealed vial until use; low humidity environment recommended |
| Short-term storage (lyophilised) | 2–8°C | Acceptable for up to 4 weeks; desiccated |
| Transit | Ambient; cold-chain packaging included | Lyophilised form is stable during standard UK domestic shipping |
Note: Reconstituted solution storage, solvent selection, working concentration, and pH guidance are not provided, consistent with Core Research’s Research Use Only supply policy. Researchers should refer to their institutional SOPs and the published literature for handling reconstituted copper peptide solutions.
Analytical Note — Core Research Quality Team
GHK-Cu presents a distinctive analytical signature: the Cu²⁺ isotope pattern in ESI-MS (⁶³Cu/⁶⁵Cu ratio ≈ 2.24) provides a reliable identity check that distinguishes the intact copper complex from the free tripeptide GHK or partially dechelated material. Our QC team verifies this isotope pattern on every batch before release. Batches where the copper isotope pattern is absent or atypical are rejected regardless of HPLC purity result, as a high HPLC purity score alone cannot confirm that the copper chelate is intact. Batch-specific analytical data is available via the CoA Portal.
Frequently Asked Questions
What is the molecular weight of GHK-Cu?
The molecular weight of GHK-Cu (Copper(II) glycyl-L-histidyl-L-lysine) is 403.91 Da. The molecular formula is C14H23CuN6O4⁺ and the CAS number is 89030-95-5. Note that CAS 49557-75-7 refers to the free tripeptide GHK (without copper), which is a structurally distinct compound.
Why does GHK-Cu appear blue-green?
GHK-Cu commonly presents as a blue-green material consistent with copper(II) complexation. Copper(II) complexes absorb light in the red-orange region of the visible spectrum (~600–700 nm) and therefore appear blue-green. Appearance may be recorded during receiving inspection, but product identity should be established from the applicable analytical documentation — specifically the ESI-MS result on the batch-specific CoA — rather than colour alone.
What is the difference between the 50mg and 100mg formats?
The GHK-Cu 50mg and GHK-Cu 100mg formats contain the same active compound at the same purity specification. The 50mg format is suitable for smaller-scale or pilot studies; the 100mg format is designed for research programmes requiring larger quantities. Both formats are supplied with batch-specific CoA documentation. The 50mg format is supplied as a refill vial compatible with the Core Research Peptide Pen system.
Is a Certificate of Analysis available?
Yes. Batch-specific CoA documents — including annotated HPLC chromatograms, ESI-MS data, and ICP-MS copper content data — are available through the Core Research CoA Portal and are included with each order.
Regulatory and Compliance Status
GHK-Cu 50mg Refill is supplied strictly for in vitro laboratory and research use only. It must not be administered to humans or animals. For the full supply boundary, refer to the RUO Compliance Policy.
Research context
The published literature on this material is summarised in the laboratory guides linked below. This record describes the material as supplied: identity, format, analytics, storage and documentation. It does not describe effects, and none should be inferred from the catalogue category.
Research Use Only — Not for Human or Veterinary Use
GHK-Cu is supplied exclusively for in vitro laboratory and pre-clinical research. Not for human or veterinary use. No formulation, application, or usage guidance is provided. Purchase confirms the buyer is a qualified researcher.
