GHK-Cu vs Pal-GHK: what is the difference between the copper peptide and the palmitoyl tripeptide?

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); The tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+ stimulates matrix metalloproteinase-2 expression by fibroblast cultures, Life Sci 2000 (PubMed 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?

Source: PubChem CID 71587328: GHK-Cu; PubChem CID 10231864: Palmitoyl tripeptide-1

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)

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.

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