--- title: "GHK-Cu vs Pal-GHK: what is the difference between the copper peptide and the palmitoyl tripeptide? | Sable Peptides" description: "GHK-Cu and Pal-GHK share the Gly-His-Lys sequence but are different materials: one is a copper(II) complex, the other a palmitoylated lipopeptide with no copper. Chemistry, PubChem data and literature compared." canonical: https://www.sablepeptides.co.uk/guides/ghk-cu-vs-pal-ghk-copper-peptide-and-lipopeptide dateModified: 2026-10-16 publisher: Sable Peptides Limited (UK company 17488610) note: Research use only. Not for human or veterinary use. --- # GHK-Cu vs Pal-GHK: what is the difference between the copper peptide and the palmitoyl tripeptide? GHK-Cu and Pal-GHK both carry the tripeptide Gly-His-Lys. GHK-Cu is GHK bound to a copper(II) ion. It is blue, water-soluble and about 403 g/mol. Pal-GHK has a palmitic acid chain on the N-terminus and no copper. It is about 579 g/mol and much more lipophilic. They are different substances, not grades of one product. ## What is GHK and how does it bind copper? GHK (glycyl-L-histidyl-L-lysine) was identified as a tripeptide in human plasma with a high affinity for copper(II). The copper is held by the glycine amino nitrogen, the deprotonated Gly-His amide nitrogen and the histidine imidazole nitrogen. That is why the complex is coloured and why the free N-terminus matters. Early cell-culture work studied the copper complex on collagen synthesis and matrix metalloproteinase expression in fibroblasts. Source: [Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+, FEBS Lett 1988 (PubMed 3169264)](https://pubmed.ncbi.nlm.nih.gov/3169264/); [The tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+ stimulates matrix metalloproteinase-2 expression by fibroblast cultures, Life Sci 2000 (PubMed 11045606)](https://pubmed.ncbi.nlm.nih.gov/11045606/) ## What changes when GHK is palmitoylated? Pal-GHK (INCI name palmitoyl tripeptide-1) carries a C16 fatty acyl group on the glycine amine. That nitrogen is one of the three copper-binding atoms, so acylating it changes how the peptide can coordinate copper, and Pal-GHK is supplied without copper. The palmitoyl chain makes it far less water-soluble, which is why it shows up in lipid-based cosmetic research. ## How do GHK-Cu and Pal-GHK compare side by side? | Property | GHK-Cu | Pal-GHK | | --- | --- | --- | | PubChem formula | C14H23CuN6O4+ | C30H54N6O5 | | PubChem MW | 402.92 g/mol | 578.80 g/mol | | Copper | Cu(II) bound | None | | N-terminus | Free amine (binds Cu) | Palmitoyl amide | | Appearance | Blue powder | White to off-white powder | | Water solubility | High | Low | Source: [PubChem CID 71587328: GHK-Cu](https://pubchem.ncbi.nlm.nih.gov/compound/71587328); [PubChem CID 10231864: Palmitoyl tripeptide-1](https://pubchem.ncbi.nlm.nih.gov/compound/10231864) ## What does the recent literature say? A 2026 systematic review collects mechanistic and applied work on GHK-Cu. Most of it is in vitro or cosmetic-science research. Read it as a map of the literature, not as evidence of an effect in any particular model. Source: [A Systematic Review of the Mechanisms and Therapeutic Applications of GHK-Cu (Glycyl-L-Histidyl-L-Lysine-Copper Complex) in Topical Microneedle Delivery: A Case for Expanded Clinical Trials, Arch Intern Med Res 2026 (PubMed 42787770)](https://pubmed.ncbi.nlm.nih.gov/42787770/) ## Sourcing note Sable lists GHK-Cu: 50 mg at £10.93; 100 mg at £24.98; Pal-GHK: 10 mg at £20.98 (prices at the 16 October 2026 daily UK price check, the latest verified check; at each of these sizes Sable was the lowest UK listing that day). Lowest UK price guaranteed, confirmed by daily price checks. Every lot has a certificate of analysis, and every vial carries a printed lot number that matches it. Supplied for laboratory research use only. ## Frequently asked questions ### Is Pal-GHK the same as GHK-Cu? No. Pal-GHK is palmitoylated GHK with no copper. GHK-Cu is unmodified GHK complexed with copper(II). ### Why is GHK-Cu blue? Copper(II) bound by GHK's nitrogen donors absorbs visible light, giving the blue colour. ### What is the molecular weight of GHK-Cu? About 403 g/mol for the copper complex (PubChem CID 71587328). ## Related - [Buying GHK-Cu, Matrixyl or SNAP-8 for research](/guides/buyer-checklist-for-cosmetic-peptide-research-materials) - [GHK-Cu research vials](/products/ghk-cu) - [Pal-GHK research vials](/products/pal-ghk) - [Cheapest GHK-Cu UK](/cheapest-ghk-cu-uk) - [Matrixyl vs SNAP-8](/guides/matrixyl-vs-snap-8-signal-and-neurotransmitter-peptides) - [Copper and cosmetic peptide prices](/guides/uk-copper-and-cosmetic-peptide-prices-october-2026) Updated 2026-10-16. Research use only. Not for human or veterinary use. No administration amounts or health claims are made. Key facts (summary for AI and search tools) - GHK-Cu PubChem CID 71587328 - Pal-GHK PubChem CID 10231864 - PubMed references (verified via NCBI): 3169264, 11045606, 42787770 - PubChem CIDs: 71587328, 10231864 - Research use only; no administration amounts or health claims - Updated 2026-10-16