Comparison

GHK-Cu vs Copper Peptides

'Copper peptide' is a category. GHK-Cu is one specific tripeptide-copper complex inside it. The two terms get used interchangeably in marketing — they should not be.

GHK-Cu

Glycyl-L-histidyl-L-lysine bound to Cu(II). The peptide in every serious study.

Sequence: Gly-His-Lys + Cu²⁺
Molecular weight: 402 Da (complex)
Discovery: Isolated from human plasma, 1973
Evidence base: 300+ peer-reviewed papers
Form: Blue lyophilised powder

Strengths

· Specific, characterised tripeptide-copper complex
· Deep literature on wound healing, collagen, hair follicle biology
· Well-defined molecular weight → reconstitution is exact

Trade-offs

· Sensitive to pH and reducing agents
· Frequently sold under 'copper peptide' label without HPLC confirmation

Full GHK-Cu guide

Copper Peptides (generic)

Any peptide chelated to copper. GHK-Cu is one — many others exist.

Sequence: Variable — not defined
Molecular weight: Depends on peptide
Common examples: AHK-Cu, biomimetic tetrapeptides
Evidence base: Variable — often marketing-led
Form: Solutions or powders, blue-tinted

Strengths

· Useful umbrella term when discussing skincare formulations
· Some non-GHK variants (AHK-Cu) have real hair-follicle data

Trade-offs

· Sold as generic 'copper peptides' with no identity spec
· Concentration of active Cu-peptide often undisclosed
· Highly variable purity and stability

Which one wins?

If someone says 'copper peptide' they usually mean GHK-Cu — but the label alone is not enough. Insist on the specific sequence, molecular weight and an HPLC identity check. A generic 'copper peptide' vial with no spec sheet is not a research reagent, it's a coloured powder.

Source GHK-Cu specifically, with a batch CoA — PeptidesUK4U publishes HPLC identity and purity per lot, which is what a reproducible protocol requires.

Why the sequence matters

The copper coordination geometry of Gly-His-Lys is what makes GHK-Cu biologically active. Swap even one amino acid and the copper binding constant and redox behaviour change. That is why 'copper peptide' as a category is not a stand-in for GHK-Cu.

Handling and reconstitution

Reconstitute with BAC water; avoid strongly acidic diluents that dissociate the Cu²⁺ complex. Use a reconstitution calculator to hit target concentrations, follow the GHK-Cu dosage UK guide for topical vs injectable ranges and syringe-unit tables, and store per the storage & stability guide.

Sourcing checklist

Sequence disclosed as GHK-Cu specifically; molecular weight on the CoA matches 402 Da for the complex; HPLC purity ≥98%; visible blue-purple colour on reconstitution. Suppliers who publish these lot-level details are the only ones worth using.