The short version of glycyl-histidyl-lysine fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-03-24. Anything still debated is marked as such rather than presented as settled.
The sequence now called GHK was first reported in the early 1970s after isolation from human plasma, where it was noted to influence liver cell behavior in laboratory preparations. Later work described a copper-binding form and its activity in fibroblast and wound-model experiments. Review articles frequently group the substance with other copper peptides. Concentrations in blood appear to fall with age in several small surveys, although the reason for this trend is not settled. Whether such a decline carries functional consequences remains an open question.
Published work on GHK-Cu concentrates largely on cell culture systems rather than whole organisms. Frequently used endpoints include collagen synthesis, expression of matrix metalloproteinases, and migration of fibroblasts. Some reports describe antioxidant behavior, while others stress delivery of copper into cells. These mechanisms are proposed rather than demonstrated, and the relative weight of each pathway is unclear. Human trials are few and generally small, so laboratory findings should not be read as confirmed clinical results.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The peptide backbone consists of glycine, histidine, and lysine joined in that order. Copper is held through the imidazole nitrogen of histidine and the alpha-amino group at the N-terminus, which together produce a square-planar arrangement around the metal center. The solid appears blue to violet, a color that originates from d-d electronic transitions within the copper coordination sphere. The complex is indexed under CAS number 89030-95-5.
Laboratory characterization of GHK-Cu typically combines separation, spectroscopic, and elemental techniques. Reverse-phase high-performance liquid chromatography is widely used to assess peptide purity, often with ultraviolet detection near the copper-related absorption band or with mass spectrometry for identity confirmation. Because the molecule contains copper, elemental methods such as inductively coupled plasma mass spectrometry or atomic absorption spectroscopy are used to quantify metal content and confirm stoichiometry. No single universal pharmacopeial monograph exists for GHK-Cu. Laboratories therefore validate their own methods, and reported purity values depend on the chosen assay and calibration standards.
Stability of GHK-Cu is influenced by light, oxygen, moisture, pH, and temperature. Solid material is generally kept desiccated and frozen to reduce hydrolysis and oxidation, while aqueous solutions are best prepared fresh or stored cold in aliquots. Repeated freeze-thaw cycles can promote aggregation, precipitation, or peptide degradation. Copper coordination may change under strongly acidic or alkaline conditions, potentially altering the complex's spectroscopic properties. Published long-term stability data for specific matrices, such as cosmetic emulsions or biological buffers, are limited, so shelf-life claims should be treated as formulation-specific rather than universal.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Copper(II) peptide complex | Peptide chain coordinated to a single metal ion |
| CAS number | 89030-95-5 | Indexed for the peptide-copper complex |
| Molecular formula | C14H22CuN6O4 | Approximate formula for a one-to-one complex |
| Appearance | Blue to violet solid | Color from copper d-d transitions |
| Solubility class | Freely soluble in water | Also dispersible in some polar solvents |
The copper-binding activity of this sequence was described in the 1970s during studies of liver tissue and plasma factors. Early work identified the peptide as a component that influenced copper uptake by cells and that appeared in wound fluid. Later investigations examined its presence across species, reporting the same chain in human and animal samples. A decline in measured concentration with age became a recurring observation, although the underlying causes remain incompletely characterised.
Published studies describe the complex in several research contexts, including collagen synthesis, antioxidant behaviour, and wound repair models. Much of this work is conducted in cultured cells or in small animal systems, and the findings are frequently cited in reviews of copper peptides. Direct clinical evidence in humans is comparatively limited, and reported outcomes vary with formulation and study design. Whether free chain or metal-bound form was used is not always stated, a point that complicates comparison between reports.
GHK-Cu is a coordination complex formed between the peptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The unbound chain, abbreviated GHK, consists of three amino acids and occurs naturally in human plasma, saliva, and urine. Binding of the metal is mediated mainly by the imidazole nitrogen of the histidine residue together with backbone amides, producing a stable chelate. Ingredient nomenclature often lists the same substance as copper tripeptide-1. Its charge and solubility behaviour differ from those of the metal-free chain.
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.
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.
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.
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.
GHK-Cu is the copper complex of the tripeptide glycyl-L-histidyl-L-lysine, a short sequence found naturally in human plasma, saliva and urine. Loren Pickart reported the isolation of the free peptide in 1973 while studying factors that influenced the growth of aged liver cells in culture. The peptide was later shown to bind copper(II) with high affinity, and the metal-bound form became the focus of most subsequent research. Its concentration in circulation declines markedly with age, a pattern that is well documented, though the physiological consequences of that decline remain debated.
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.
The study of diagenesis in rocks is used to understand the geologic history they have undergone and the nature and type of fluids that have circulated through them. From a commercial standpoint, such studies aid in assessing the likelihood of finding various economically viable mineral and hydrocarbon deposits. The process of diagenesis is also important in the decomposition of bone tissue.
=== Organoberkelium compounds === Berkelium forms a trigonal (η5–C5H5)3Bk metallocene complex with three cyclopentadienyl rings, which can be synthesized by reacting berkelium(III) chloride with the molten beryllocene (Be(C5H5)2) at about 70 °C. It has an amber color and a density of 2.47 g/cm3. The complex is stable to heating to at least 250 °C, and sublimates without melting at about 350 °C. The high radioactivity of berkelium gradually destroys the compound (within a period of weeks). One cyclopentadienyl ring in (η5–C5H5)3Bk can be substituted by chlorine to yield [Bk(C5H5)2Cl]2. The optical absorption spectra of this compound are very similar to those of (η5–C5H5)3Bk. Berkelium also forms berkelocene, an actinocene complex, with substituted cyclooctatetraenides.
=== Novel technologies === Tecemotide is based on novel technologies, which may raise new regulatory issues that could delay or complicate regulatory approval. Additionally, as of 2013, the FDA had approved for commercial sale in the United States only one active vaccine designed to stimulate an immune response against cancer. Consequently, there is limited precedent for the successful development or commercialization of products based on these technologies in this area.
Sources: en.wikipedia.org
== External links == Conserve O Gram – Preparing And Storing Herbarium Specimens The Institute of Conservation – Care and Conservation of Botanical Specimens Natural Sciences Collections Association – Pest Management, Prevention and Control Natural Sciences Collections Association – Vascular plants Melinda Peters – Conservation Process of Water-damaged Herbarium Specimens at the Harvard University Herbaria Preservation of Herbarium Specimens: An Archive Conservator's Approach
== Structure == The notochord is a long, rod-like midline structure that develops dorsal to the gut tube and ventral to the neural tube. The notochord is composed primarily of a glycoproteins core that is encased in a sheath of collagen fibers. This is wound into two opposing helices. The glycoproteins are stored in vacuolated, turgid cells, which are covered with caveolae on their cell surface. The angle between these fibers determines whether increased pressure in the core will result in shortening and thickening versus lengthening and thinning. Alternating contraction of muscle fibers attached to each side of the notochord result in a side-to-side motion resembling stern sculling, which allows locomotion. The stiffened notochord prevents movement through telescoping motion such as that of an earthworm.
food and dietary supplement labeling purposes, the amount in a serving is expressed as a "percent of daily value" (%DV). For vitamin B12 labeling purposes, 100% of the daily value was 6.0 μg, but on 27 May 2016, it was revised downward to 2.4 μg (see Reference Daily Intake). Compliance with the updated labeling regulations was required by 1 January 2020 for manufacturers with US$10 million or more in annual food sales, and by 1 January 2021 for manufacturers with lower volume food sales.
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Sources: en.wikipedia.org
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=== Available forms === Each Contrave tablet contains 8 mg naltrexone and 90 mg bupropion. Once full dosing is reached (after 4 weeks of administration), the total dosage of Contrave for treating overweight or obesity is two tablets twice daily or 32 mg naltrexone and 360 mg bupropion per day.
To achieve the goal of tissue reconstruction, scaffolds must meet some specific requirements. High porosity and adequate pore size are necessary to facilitate cell seeding and diffusion throughout the whole structure of both cells and nutrients.
Sources: en.wikipedia.org
It is the copper complex of the tripeptide glycyl-L-histidyl-lysine. The metal ion is held by the histidine imidazole group and the peptide N-terminus. Most research on it concerns skin and wound models.
The tripeptide was first isolated from human plasma and has also been reported in saliva and urine. Plasma levels appear to decline with age in some small studies. Those observations rest on limited sample sizes.
It is not authorized as a systemic medicine in most countries. Cosmetic preparations list it as an ingredient rather than an active pharmaceutical substance. Legal status therefore differs by jurisdiction.
Identification usually combines reverse-phase high-performance liquid chromatography with mass spectrometry. The copper content can be measured separately by inductively coupled plasma mass spectrometry or atomic absorption spectroscopy. The combination helps distinguish the intact complex from free peptide or free copper.