What is GHK-Cu?

Structure: a copper-binding tripeptide

GHK-Cu is the copper complex of GHK, a tripeptide made of three amino acids, glycine, L-histidine and L-lysine, joined in that order (hence GHK, from the single-letter codes for each amino acid). The peptide itself was first identified as a naturally occurring component of human plasma, and it has a strong, specific affinity for copper ions (Cu2+), which it binds through coordination bonds formed primarily by the histidine side chain together with the peptide backbone.

This copper-binding property is central to the compound's chemistry: GHK-Cu behaves as a distinct, stable metal-peptide complex rather than simply as free peptide mixed with free copper, and much of the research literature on this compound specifically studies the complexed form rather than the peptide alone.

Collagen and the extracellular matrix

A substantial part of the published research literature on GHK-Cu concerns the extracellular matrix, the network of proteins including collagen that surrounds and supports cells in connective tissue. Laboratory studies using cell and tissue culture models have examined how exposure to GHK-Cu is associated with changes in the activity of cells responsible for producing and remodelling this matrix, including studies looking at collagen-related proteins specifically.

This research is generally conducted in fibroblast cell cultures or related tissue models, and describes molecular and cellular observations under laboratory conditions rather than outcomes measured in human clinical studies. A small number of topical human studies exist, and a Phase 2 trial of topical GHK-Cu (NCT07437586) has been recruiting since February 2026; no therapeutic effect has been established.

Gene-expression studies

GHK-Cu has also been examined in gene-expression research, where techniques such as microarray or gene-array analysis are used to measure how exposing cultured cells to the compound changes the activity levels of large numbers of genes simultaneously. This type of study is used across cell biology broadly to build a picture of which cellular pathways respond to a given compound, and GHK-Cu is one of the peptide compounds that has been studied this way in the published literature, contributing to research interest in its mechanisms at a molecular level.

Why the copper complex matters for research design

Because GHK-Cu's activity in laboratory studies is tied to its specific copper-bound structure, researchers designing experiments with this compound generally need to consider the complex as the unit of study, rather than treating the peptide and copper as interchangeable with separately sourced peptide and copper salts. This is a structural chemistry point relevant to experimental design, not a claim about any effect in a living organism.

How GHK-Cu is supplied for research

As with other research peptides, GHK-Cu supplied for laboratory use is typically characterised by HPLC for purity and by mass spectrometry or a reference standard for identity. Certificates for the GLOW and KLOW pens are being re-issued and are not yet published, so no GLOW or KLOW test result is claimed here. Celyfe includes GHK-Cu at 75mg per 3ml cartridge in its GLOW Pen and KLOW Pen, alongside BPC-157, TB-500 and, in KLOW's case, KPV, shipped cold-chain and stored refrigerated between 2 and 8 degrees Celsius.

Research use only

GHK-Cu supplied by Celyfe is intended for laboratory and research use only. It is not an approved medicine or cosmetic ingredient in the products sold here, and nothing in this guide describes or implies its use in or on a human or animal body.