Published by Peptide Protocols · Reviewed September 2026 · How we make these pages · Educational & research purposes only — not medical advice.
GHK-Cu — the "copper peptide" — shows up everywhere in skin and anti-aging conversations, from serums to research forums. If you've been trying to separate what it actually is from the marketing, here's the plain-English version.
GHK-Cu is a small copper-binding peptide: a short chain of three amino acids (glycine-histidine-lysine, hence "GHK") bound to a copper ion (the "Cu"). It occurs naturally in the body, where its levels are studied in connection with the aging process. Because of that copper bond, it's commonly called a copper peptide. In the research world it's handled as a research compound, labeled for research use only.
GHK-Cu has a relatively long research history compared with many peptides, though much of it is still preclinical. Researchers have explored areas such as:
An honest caveat: while GHK-Cu has more literature behind it than some peptides, much is still early-stage or lab-based, and human clinical data is limited. Treat it as "what studies are exploring," not "what it's proven to do for people." Always work with a qualified professional.
GHK-Cu is researched in a few forms — most often a topical (the copper peptide is well known in cosmetic-science contexts) and also an injectable reconstituted from a lyophilized (freeze-dried) powder. The form changes how it's handled, stored, and measured, which is exactly the kind of detail our reference guides spell out.
If you're working with a lyophilized research form, the powder is reconstituted with bacteriostatic water before handling. The concentration you create (mg of peptide ÷ mL of water) drives every measurement after it — get that number right and everything downstream stays accurate. Our cheat sheets and Universal Excel Logbook do this math for you with tick-mark tables for dozens of peptides, including GHK-Cu.
This is where most people get burned — quality varies wildly between suppliers. Before buying from anyone, check that they:
We do not recommend or partner with any peptide supplier. Use the checklist instead: third-party COAs that match your batch and lot, stated purity, clear research-use labeling, real support and proper cold-chain shipping.
The supplier checklist →Educational content only. Confirm the legal status where you live before ordering anything.
It's typically sold labeled for research use only — not for human consumption. Regulations vary by country and change over time, so always confirm what's permitted in your location. This is educational content, not legal advice.
Because the GHK peptide is bound to a copper ion (Cu). That copper component is central to how the molecule is studied, and it's why you'll see "copper peptide" used as a nickname across skincare and research discussions.
It's featured across several — including the Skin, Hair & Nails, Hair Loss, and Longevity cheat sheets.
Get the per-compound cheat sheets — the research, reconstitution math, timing, and a tracking logbook in one place.
Browse the full library on Etsy →The one formula, a BAC-water chart, and the 10 most-researched beginner peptides — the math done for you. Print it for the fridge.
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