Copper tripeptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-09-05. Numbers and descriptions here follow the published literature rather than marketing material.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The peptide sequence is often abbreviated Gly-His-Lys, and the copper is bound through the histidine imidazole nitrogen and adjacent peptide nitrogens. The complex is frequently described as a 1:1 peptide-to-copper species. It occurs naturally in human plasma, saliva, and urine at low concentrations. Its endogenous levels have been reported to decline with age, although the precise physiological role of that change remains an open question.
Research interest in GHK-Cu centers on its ability to deliver copper and to influence cellular processes in laboratory models. In cell culture and animal studies, the complex has been linked to collagen synthesis, antioxidant enzyme activity, and expression of genes associated with tissue remodeling. These effects are not equivalent to proven clinical outcomes. The mechanisms proposed include copper transfer to cuproenzymes, modulation of growth factor signaling, and interactions with extracellular matrix components. How much of the observed activity depends on intact GHK-Cu versus free copper or free peptide is not fully resolved.
The peptide was first isolated from human albumin in 1973 by Loren Pickart, who later described its copper-binding behavior. Early work linked the complex to wound healing and tissue remodeling. Plasma levels of GHK decline with age, a pattern that stimulated interest in topical and supplemental applications. Researchers have reported that the tripeptide influences collagen synthesis, antioxidant defense, and inflammatory signaling in cell and animal models. Human clinical evidence remains limited and often relies on small studies.
Commercial products list GHK-Cu as copper tripeptide-1, a cosmetic ingredient. Formulators value its blue color and water solubility, which allow incorporation into serums, creams, and masks. Regulatory treatment varies: in the United States it appears in cosmetics, while some jurisdictions classify certain claims as drug-like. The compound is not an approved drug for any indication. Studies continue to examine its effects on skin, hair, and wound repair, but dosage, delivery, and long-term safety questions remain open.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Copper-binding tripeptide complex | Includes Gly-His-Lys and Cu(II) |
| Molecular formula | C14H22CuN6O4 | Reported for the 1:1 complex |
| Appearance | Blue to blue-violet solid | Color arises from copper d-d transitions |
| Solubility class | Water-soluble; slightly soluble in polar organic solvents | Often prepared as aqueous stock |
| Typical storage | -20 °C, desiccated, protected from light | Limits oxidation and moisture uptake |
The compound was first isolated from human plasma in the 1970s by Loren Pickart, who later described copper-binding activity in liver and other tissues. Early reports focused on its presence in blood and its ability to carry copper between proteins. Commercial and cosmetic use of the term 'copper peptide' has since broadened, and labels rarely distinguish GHK-Cu from other copper-binding fragments. This naming overlap makes literature searching harder, because cosmetic ingredient lists, supplier catalogues and laboratory papers use different vocabularies for the same molecule.
GHK-Cu is the copper-binding complex formed by the tripeptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The free peptide is usually written as GHK, and the complex is written as GHK-Cu or Cu-GHK. The sequence was identified in human plasma and later detected in saliva and urine. Its name comes from the single-letter codes of glycine, histidine and lysine. The complex is widely described as a naturally occurring carrier of copper in blood rather than as a free peptide with its own hormonal role.
Copper binds to the peptide through the histidine imidazole nitrogen and the terminal amino group, forming a stable square-planar complex. Binding constants reported for copper(II) with GHK are high, so the peptide competes effectively for copper in solution. The complex absorbs visible light, which gives solutions a blue to violet colour. Whether the metal-free peptide has a distinct biological function of its own is still an open question; some work treats it mainly as a copper delivery vehicle, while other work reports peptide-specific effects.
Quality specifications for research material commonly state peptide purity, copper stoichiometry, counter-ion identity, and residual water content. Frequent counter-ions include acetate and trifluoroacetate, which differ in mass and in their effect on solubility and handling. Whether batch-to-batch differences in reported responses trace to these parameters or to assay conditions remains an open question, since published comparisons rarely control for all of them at once. Independent verification therefore normally pairs a purity measurement with an elemental copper measurement on the same lot.
Practical handling notes centre on limiting exposure to water, oxygen, and repeated temperature cycling. Weighed powder is often equilibrated to room temperature before opening to avoid condensation on the solid. Working solutions are typically divided into single-use aliquots and frozen rather than stored refrigerated for long periods. Reported shelf lives vary widely between laboratories, and no single set of conditions is universally treated as a reference standard, which complicates direct comparison of published stability figures.
=== Clubs === University of Galway has more than 40 sports clubs based on campus, ranging from indoor sports (such as archery, badminton, fencing, weightlifting, table tennis, and squash), to water sports (such as rowing, kayaking, sailing, windsurfing, and scuba diving), as well as martial arts (such as judo, karate, aikido, Muay Thai, kendo, and taekwondo), plus equestrian, triathlon, athletics, and snow sports. The university also competes in the most popular Irish field sports of association football, Gaelic football, hurling, and rugby union, as well as cricket, hockey, and lacrosse. University of Galway GAA compete in the Sigerson Cup (Gaelic football) and the Fitzgibbon Cup (hurling). They are the second most prolific winners of the Sigerson Cup. University of Galway RFC compete in the Connacht Senior Cup, and are the competition's most successful side with 34 wins. University of Galway F.C. compete in the Galway & District League, the Colleges and Universities Football League (CUFL), Collingwood Cup and Harding Cup (Freshers). They previously competed in the Connacht Senior League under their former name of NUI Galway F.C. and won the competition in 1990, as UCG. The campus is home to a wide range of sport facilities. Facilities include Dangan Sportsground, where the university's GAA teams compete, and the Kingfisher, where Moycullen Basketball Club play their games.
A third trial, Trial 3, was conducted during 2007–2008 in Gabon and Malawi. In Trial 1, the most common adverse reactions in participants with malaria treated with IV artesunate were acute renal failure requiring dialysis, hemoglobinuria and jaundice. The safety profile in Trial 2 was generally similar to Trial 1. One trial was used to evaluate both, safety and benefits of artesunate. The trial enrolled participants with severe malaria who needed hospitalization because of their condition. Participants received at random either artesunate or a medicine used to treat malaria (quinine). Participants and the health care providers knew which treatment was being given. The benefit of artesunate in comparison to quinine was evaluated by comparing the number of participants who died while in the hospital (in-hospital mortality). The benefit of artesunate was supported by the data from Trial 2 in which pediatric participants younger than 15 years of age with severe malaria were randomly assigned treatment with artesunate or quinine. The application for IV artesunate was granted priority review and orphan drug designations. The FDA granted approval of artesunate for injection to Amivas.
== Commercialization == ChromaDex (now Niagen Bioscience) licensed patents for nicotinamide riboside from Dartmouth College, Cornell University, and Washington University in St. Louis in July 2012. The company developed a commercial production process for nicotinamide riboside chloride, trademarking the active ingredient as Niagen. ChromaDex has continued to expand using the brand name Tru Niagen globally while also supplying Niagen as an ingredient to other manufacturers. ChromaDex was in a patent dispute with Elysium Health over the rights to nicotinamide riboside supplements between 2016 and 2023. ChromaDex holds multiple patents related to nicotinamide riboside, including manufacturing methods, compositions, and uses. As of 2023, ChromaDex's patent portfolio for nicotinamide riboside includes 50+ granted patents and numerous pending patent applications worldwide. As of March 19, 2025, ChromaDex was renamed Niagen Bioscience, and now trades under the Ticker Symbol 'NAGE'.
==== Fragmentation tree computation ==== A fragmentation tree is a representation of the fragmentation process similar to "fragmentation diagrams" created by experts. The fragmentation tree annotates the MS2 spectrum by providing a molecular formula for each fragment peak. Peaks that do not receive an annotation are considered noise peaks. The fragmentation tree also predicts the fragmentation reactions (called losses) leading to the fragment peaks. Fragmentation trees are a valuable tool for deducing information about the fragmentation but are not a precise depiction of the actual fragmentation process. To identify the molecular formula of an unknown molecule, a separate fragmentation tree is computed for every molecular formula candidate. In other words, the method attempts to reconstruct the fragmentation process that led to this MS2 spectrum for each candidate molecular formula. This allows to compare the different hypotheses that a particular candidate is actual the correct molecular formula. The best-scoring fragmentation tree (i.e. the fragmentation process that is best explaining the spectrum) corresponds to the most likely molecular formula explanation.
Sources: en.wikipedia.org
=== Czech Republic === After joining NATO, the Army of the Czech Republic developed a combat ration known as the BDP (Czech: Bojová Dávka Potravin). The BDP comes in two versions, type I and II, each holding two ready-to-eat main courses packed in large foil "cans" (beef roast with rice, pork goulash with potato, spicy risotto, pork with carrots and vegetables, etc.), a small plastic cup of lunch meat spread, cheese spread, hard bread, cookies, jam, instant coffee, tea bags, fruit-flavored multivitamin drink tablets, vitamin C enriched fruit drink powder, a chocolate bar, sugar, salt, chewing gum, wet napkins, paper towels, a plastic bag, and a menu and instruction sheet. A modified version of the BDP known as the KDP (Czech: Konzervovaná Dávka Potravin) is also used. This contains the same items as the BDP, but adds an aluminium cup, plastic utensils, a folding stove with fuel tablets and matches, and soap.
=== Catalyst support === Diatomaceous earth also finds some use as a support for catalysts, generally serving to maximize a catalyst's surface area and activity. For example, nickel can be supported on the material—the combination is called Ni–Kieselgur—to improve its activity as a hydrogenation catalyst.
Otherwise: Cut the potato into slices as shown above, stew with Spanish wine, oil and nutmeg. (French: Tartoufle autrement. Conppez la tartoufle par tranches comme deſſus, & la mettez eſteuuer avec vin d'Eſpagne & nouveau beure, & noix muſcade.)
Transcription of insulin is regulated by the binding of various transcription factors to the ~400 base pairs before the insulin transcription start site, called the "insulin regulatory sequence". This sequence is made up of several distinct regions with different biochemical properties, each of which serve as binding sites for distinct regulatory proteins. First, multiple A/T-rich sequences, called "A elements", each of which contains a "TAAT" reocognized by homeodomain proteins. These regions are primarily bound by PDX-1, but also Cdx2 and Isl-1. Second, two so-called "C elements" – C1 located 107–118 base pairs before the transcription start site; C2 311–317 base pairs before the start site. C1 is bound by RIPE3b1 via MafA. C2 (also called the "pancreatic islet cell enhancer sequence" or "PISCES") is bound by PAX6. Third, an "E element" (two in rodents) with sequence GCCATCTG is 91–100 base pairs before the transcription start site and binds the helix-loop-helix transcription factors NEUROD1. Lastly, several "cyclic AMP response elements" with sequence TGACGTCA that binds CREB. In humans, a "Z-element" resides 243–292 base pairs before the start site and binds a complex called ZaI, as well as PDX-1 and MafA.
=== Oxytocin === Oxytocin is responsible for the milk let-down reflex as a response to neonate suckling. It is released from the posterior pituitary gland in a pulsatile manner, via stimulation of the vagus nerve. This causes myoepithelial cells, which surround the mammary alveoli, to contract. Oxytocin injections have been found to increase milk yield in cows. The role of oxytocin in the neonate is yet quite unclear, however we know that oxytocin has an important role in empathy and bonding between pairs.
Sources: en.wikipedia.org
GHK-Cu is a complex of the tripeptide glycyl-L-histidyl-L-lysine with copper(II). The peptide binds copper through its histidine residue and neighboring amide nitrogens, forming a stable coordination compound. It is studied as a research chemical and used in some cosmetic formulations.
Yes, the peptide and its copper complex have been detected in human plasma, saliva, and urine. Endogenous concentrations are low, and reported levels change with age and physiological state. The biological significance of those changes is still an active area of study.
GHK refers to the free tripeptide without a bound copper ion. GHK-Cu contains copper(II) coordinated to the same peptide backbone. The presence of copper affects the complex's color, stability, and interaction with biological molecules.
GHK is the free tripeptide, while GHK-Cu includes a bound copper(II) ion. The copper complex is the form most often studied for skin and wound-related activity. The two names are sometimes used interchangeably in product labeling, but they refer to distinct chemical species.