If you have been reading about redox activity and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-07-10. Numbers and descriptions here follow the published literature rather than marketing material.
The peptide portion consists of three amino acids: glycine, histidine and lysine. Copper(II) coordinates through the imidazole nitrogen of histidine, the alpha-amino group of glycine and a deprotonated amide nitrogen of the backbone, producing a roughly square-planar geometry. This arrangement gives the complex its characteristic blue-to-violet colour and helps it resist dissociation in water. Reported stability constants are high, although values differ between studies because of differences in ionic strength and measurement method.
The International Nomenclature of Cosmetic Ingredients lists the substance as copper tripeptide-1, the name that appears on most topical product labels. Related designations include copper peptide and GHK-Cu, and the hyphenated form is common in research literature. In cosmetics the material is regulated as an ingredient rather than as a drug, so products may reach the market without evidence of the effects claimed for them. Whether those effects are clinically meaningful is an open question, since most supportive data come from laboratory work and small trials.
Endogenous GHK occurs in blood plasma, saliva, and urine, and reported plasma concentrations decline with age in several studies. Researchers have proposed that the peptide acts as a copper carrier that delivers the metal to cells and to sites of injury. That transport role is a hypothesis supported by binding measurements and tissue-distribution data rather than a settled mechanism, and the peptide is generally described as a minor contributor to total plasma copper transport. Values reported in wound fluid and certain tissue extracts are higher than in circulating plasma.
The sequence carries three residues in the order glycine, histidine, lysine, which places a small, flexible chain around a single metal centre. Compared with larger copper-binding proteins, the complex is compact and its coordination chemistry can be reproduced with synthetic peptide in a laboratory. Published structural work agrees on the nitrogen donor set but differs in the exact geometry assigned under some conditions, so the arrangement is best treated as well characterised in outline rather than fixed in every detail.
| Property | Value | Notes |
|---|---|---|
| INCI name | Copper tripeptide-1 | Standard designation on cosmetic ingredient labels |
| Peptide sequence | Gly-His-Lys | Three-residue ligand; binding occurs at the histidine side chain |
| Metal-to-peptide ratio | 1 to 1 | One copper(II) ion per peptide unit |
| Appearance | Blue to violet powder | Colour arises from copper-to-peptide electronic transitions |
| Water solubility | Freely soluble | Commonly formulated in aqueous or water-alcohol systems |
Laboratory studies describe GHK-Cu as a source of copper that cells can take up, with reported effects on collagen, elastin, and glycosaminoglycan synthesis in cultured fibroblasts. The peptide also appears in wound-repair research, where it is linked to the activity of matrix metalloproteinases and their inhibitors. These observations come largely from cell and animal models. How directly the complex controls any single pathway in intact human skin remains an open question, and reported effects depend on concentration, vehicle, and exposure time.
Copper takes part in redox chemistry, and the same property that makes it useful in enzymes can generate reactive oxygen species when the ion is loosely bound. GHK chelates copper through imidazole, amino, and amide nitrogen donors, which reduces the amount of free copper in solution. Whether that chelation is protective, neutral, or harmful in a given tissue is not settled. Laboratory assays report both antioxidant and pro-oxidant behavior, depending on the conditions and the readout used.
Published work on GHK-Cu is dominated by in vitro experiments and small animal studies. Human trials tend to be short and small, with endpoints such as skin appearance rather than clinical outcomes. Review articles often summarize the same underlying laboratory findings, which can make the evidence base look broader than it is. Several basic questions remain open: the concentration of the intact complex in human tissue, the route by which it crosses the skin barrier, and whether effects seen in culture produce measurable changes in people.
Identity and purity are established with a combination of chromatographic and spectroscopic techniques. Reversed-phase high-performance liquid chromatography separates the intact complex from peptide fragments and free copper, and the elution profile yields a purity estimate. Mass spectrometry gives the mass of the intact species and exposes degradation products. Ultraviolet-visible spectroscopy displays a broad absorption band in the visible region that is characteristic of the copper center. Nuclear magnetic resonance is less informative here, because the paramagnetic metal broadens signals and complicates spectral interpretation.
Copper content is measured separately, since a peptide assay alone does not report the metal-to-peptide ratio. Elemental techniques such as inductively coupled plasma optical emission spectroscopy quantify copper after acid digestion of the sample. The result is compared with the theoretical value for a one-to-one complex, and a shortfall indicates free peptide or partial dissociation. Suppliers differ in how they state purity, as some quote peptide content and others quote the whole complex. A defined stoichiometry therefore requires both a peptide assay and a copper assay.
Identity and purity are usually assessed with reversed-phase high-performance liquid chromatography, often paired with mass spectrometry. Copper content is measured separately by techniques such as inductively coupled plasma mass spectrometry or atomic absorption. Amino acid analysis confirms the peptide sequence after hydrolysis. Because the metal and the peptide can be quantified independently, a complete certificate of analysis normally reports both values rather than a single purity figure. This separation of measurements is important when comparing suppliers.
Solid GHK-Cu appears as a blue to blue-violet powder, and the colour is a direct consequence of copper coordination. The complex dissolves readily in water and in many polar solvents, while the free peptide behaves differently. Solubility in nonpolar media is low, which limits its use in oil-based systems. Solutions are typically prepared fresh because the dissolved form is more exposed to hydrolysis and to loss of the metal ion than the dry powder. Working concentrations are usually low, and preparation notes often specify the solvent and the order of addition.
Dry material is typically held at low temperature, often around minus twenty degrees Celsius, and protected from moisture and light. Copper complexes can release their metal ion under acidic conditions or in the presence of competing chelators. Hydrolysis of the peptide backbone is a slower but real pathway, and the histidine residue is susceptible to oxidation over long periods. Stability statements therefore depend on formulation, pH, and container, and they should be read as conditional rather than absolute.
== Clinical trials == In June 2020, CureVac was launched for phase I trial with 280 participants. In August, CureVac was launched for phase II trials with 674 participants. In November, CureVac reported results of a Phase I-II clinical trial that CVnCoV (active ingredient zorecimeran) was well-tolerated, safe, and produced a robust immune response. In December 2020, CureVac began a Phase III clinical trial of CVnCoV with 36,500 participants. Bayer will provide clinical trial support and international logistics for the Phase III trial, and may be involved in eventual manufacturing should the vaccine prove to be safe and effective. In February 2021, the EU's CHMP started a rolling review of CVnCoV. In April 2021, the same procedure began in Switzerland. In June 2021, CureVac announced that the vaccine's efficacy against symptomatic disease is 48%. The company said the high number of variants in circulation may explain the low efficacy, but some scientists attribute the result to insufficient immunogenicity due to the use of unmodified mRNA (the Pfizer–BioNTech and Moderna vaccines use uracil-modified mRNA) or the dose being too low (12 μg, compared to 30 μg for Pfizer–BioNTech and 100 μg for Moderna). Neutralizing antibody levels in CureVac recipients were about the same as those in convalescence, but much lower than those seen in recipients of Pfizer–BioNTech or Moderna. The modified mRNA induces potent antibodies and other protective immune responses and circumvents the body's inflammatory reactions.
In South India, across the first millennium CE, the Middle kingdoms transmitted Dravidian language scripts and cultural traditions to Southeast Asia. Well before the millennium's end, Judaism, Christianity, Islam, and Zoroastrianism had become established on India's southern and western coasts. Early in the 2nd millennium, Muslim armies from Central Asia intermittently overran India's northern plains, eventually establishing the Delhi Sultanate and drawing India into the cosmopolitan networks of medieval Islam. The Vijayanagara Empire established a powerful military-fiscal state that fostered a flourishing, distinctively South Indian Hindu culture. During this era, Sikhism emerged in the Punjab, promoting an egalitarian devotion that transcended traditional Hindu and Muslim boundaries. The Mughal Empire ushered in two centuries of economic expansion and relative peace, leaving a lasting legacy of administrative centralisation and cultural synthesis. The expanding rule of the British East India Company consolidated territorial control over the subcontinent while transforming India into a colonial economy. Crown rule, or the British Raj, began in 1858. Although equality before the law promised to Indians was slow to materialise, both British India and, to a lesser extent, the princely states saw technological changes as modern education and more organised public life took root. A nationalist movement emerged in India, the first in the non-European British Empire. Noted for nonviolent resistance after 1920, it was a major factor in ending British rule.
Robert Carswell (1793–1857), a British professor of pathology, and Jean Cruveilhier (1791–1873), a French professor of pathologic anatomy, described and illustrated many of the disease's clinical details, but did not identify it as a separate disease. Specifically, Carswell described the injuries he found as "a remarkable lesion of the spinal cord accompanied with atrophy". Under the microscope, Swiss pathologist Georg Eduard Rindfleisch (1836–1908) noted in 1863 that the inflammation-associated lesions were distributed around blood vessels. The French neurologist Jean-Martin Charcot (1825–1893) was the first person to recognize multiple sclerosis as a distinct disease in 1868. Summarizing previous reports and adding his own clinical and pathological observations, Charcot called the disease sclérose en plaques.
Sources: en.wikipedia.org
N-Desethyletonitazene (NDE, Noretonitazene) is a benzimidazole derivative with potent opioid effects which has been sold as a designer drug. It is better known as an active metabolite of the related compound etonitazene, but has similar activity to the parent compound and has sometimes appeared as a drug of abuse in its own right, first being identified in New Zealand in 2024.
In collaboration with the team at the Lawrence Livermore National Laboratory (LLNL) in Livermore, California, United States, they made an attempt on element 114 (which was predicted to be a magic number, closing a proton shell, and more stable than element 113). In 1998, the JINR–LLNL collaboration started their attempt on element 114, bombarding a target of plutonium-244 with ions of calcium-48:
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Sources: en.wikipedia.org
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In the 1790s European whalers arrived, bringing alcohol, prostitution, and religious missionaries along with them. In the 1820s Protestantism became the main religion on Tahiti. The European ships brought such diseases for which Tahitians had little or no acquired immunity, such as dysentery, smallpox, scarlet fever, typhoid fever, venereal disease and tuberculosis. As a result of these changes, by 1830 the population of Tahiti decreased to 15,300 from estimated 110,000 in 1767, when the ship HMS Dolphin touched on the island. The 1881 census enumerated about 5,960 indigenous Tahitians. The recovery continued in spite of more epidemics. The Pōmare Dynasty rose to prominence in the early 1790s from a ruling Tahitian family aided by protection from British mercenaries from the mutineers on the Bounty. On 29 June 1880, King Pōmare V agreed to a treaty of annexation with the French. On 9 September 1842, there was a protectorate treaty signed between Tahitians and the French. The agreement was for the "protection of indigenous property and the maintenance of a traditional judicial system." In 1958 the islands in the area including Tahiti were "reconstituted as a French Overseas Territory and renamed French Polynesia". In 2013 the United Nations relisted French Polynesia as a territory to be decolonised.
Sources: en.wikipedia.org
It is a complex of a three-amino-acid peptide, glycine, histidine and lysine, bound to a single copper(II) ion. The metal is held mainly by the histidine side chain and the peptide backbone. Most commercial material is supplied as an acetate salt rather than as the free complex.
The free peptide was reported in 1973 by Loren Pickart, who isolated it from human plasma. Its copper-binding behaviour was characterised over the following years. The metal-bound form has been the subject of most later research.
Yes. Copper tripeptide-1 is the name used in cosmetic ingredient labelling, while GHK-Cu is the shorthand found in the scientific literature. Both refer to the same peptide-copper complex, and the two terms are interchangeable in most technical documents.
It consists of a three-amino-acid peptide, glycine-histidine-lysine, bound to one copper(II) ion. The peptide supplies four nitrogen donor atoms, and the resulting complex is stable in neutral aqueous solution. The metal-free peptide is usually called GHK.