The short version of copper chelation fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-03-14 and is reviewed periodically as new material appears.
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.
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.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-lysine and a copper(II) ion. The peptide sequence is conventionally written as Gly-His-Lys, abbreviated GHK. Copper binds through the imidazole nitrogen of histidine, the alpha-amino group, and a deprotonated amide nitrogen, producing a square-planar geometry. The complex carries a net positive charge near physiological pH and is intensely blue in aqueous solution. The metal-free peptide is often written simply as GHK, while the copper-bound form is written GHK-Cu.
The compound was first isolated from human plasma by the biochemist Loren Pickart in 1973. Early work identified it as a factor that altered the behavior of cultured liver cells, and later studies linked it to connective tissue and wound-related processes. Reported plasma concentrations fall markedly between roughly age twenty and age sixty, a pattern that generated interest in copper peptide biology. Whether that decline has functional consequences remains an open question, because differences observed across age groups do not by themselves establish causation. Research interest later expanded into cosmetic and tissue-culture settings.
| 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 |
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.
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.
Quality control for GHK-Cu relies on documentation and independent testing rather than a single accepted standard. A certificate of analysis may report peptide purity, copper content, residual solvents, water content, and microbial limits, but the underlying methods and acceptance criteria vary by supplier. Verification can include mass confirmation, amino acid analysis, and comparison with a reference standard when one is available. Open questions include how different copper-binding modes or peptide isomers affect measured activity and whether conventional purity assays capture those differences. Buyers of research-grade material typically need to request raw data rather than rely solely on a summary certificate.
=== Subdivision === Traditionally Rhodiola was divided into subgenera, sections and series, based on plant characteristics. Four subgenera were recognised; Rhodiola, Primuloides, Crassipedes and Clementsia. However molecular studies have failed to demonstrate monophyly of these subtaxa.
Each single-use vial of reslizumab is formulated as 10 mg/mL reslizumab in an aqueous solution containing 2.45 mg/mL sodium acetate trihydrate, 0.12 mg/mL glacial acetic acid, and 70 mg/mL sucrose, with a pH of 5.5.
== Further reading == Abelshauser, Werner; von Hippel, Wolfgang; Johnson, Jeffrey Allan; Stokes, Raymond G. (2003). German Industry and Global Enterprise. BASF: The History of a Company. New York: Cambridge University Press. ISBN 978-0-521-82726-3. Beer, John J. The Emergence of the German Dye Industry (1959).
Sources: en.wikipedia.org
== Patents == Magnetic method of pipe-line inspection, (1950). Photoelectric colorimeter, (1950). Refractive index measurement of fluids, (1951). Process for the purification of spent sulphuric acid, (1952). Infrared gas analyzer, (1954). Improvements in and relating to the preparation of oil solutions of highly basic polyvalent metal salts of organic acids, (1956). Process for removing coal and carbonaceous material from used sulfuric acid, (1957). Improvements in or relating to apparatus for measuring vapour pressure, (1957). Improvements in and relating to the preparation of basic polyvalent metal salts of organic acids, (1958). Sulphonation of organic liquids, (1960). A method of and apparatus for separating liquid phases, (1965). Rotary separation of viscous pseudo-plastics, (1965).
Keep-it Technologies AS (formerly TimeTemp) is a spin-off technology company from The Norwegian University of Life Sciences (NMBU) in Ås, just outside Oslo in Norway. Keep-it Technologies has offices and manufacturing facilities at Furuset in Oslo. The company is primarily engaged in research and technology development of a shelf-life indicator for temperature-sensitive products, such as food, pharmaceuticals and chemicals. The company's research efforts have received financial support from the Research Council of Norway’s Food Programme, as well as from Innovation Norway’s industrial R&D scheme (IFU).
Although sometimes applied to other cultures and religions, caste is a fundamental social institution of India, most fully developed among Hindus. All Hindus fall broadly into four castes, or varnas: Brahmin, or priests, at the top; below them Kshatriya, or warriors; further below, Vaishya, or merchants and farmers; and at the bottom, Shudra, or the service class. Outside the caste system, and of traditional Hinduism, lie people formerly called "outcastes" or "untouchables," and now scheduled caste (a term used in India's constitution) or Dalit, a later self-description of pride, meaning "broken" or "downtrodden". Each caste is further divided into sub-castes, or jātis, many of which are tied to occupations. However, the custom of endogamy, or marrying within one's subcaste, makes caste a hereditary label rather than one of occupational choice and has entrenched the caste system. The Constituent Assembly of India abolished untouchability in 1947, the Republic of India did more formally in 1950, and India has since enacted other anti-discrimination laws and social welfare initiatives related to caste. Still, caste-based inequality, discrimination, segregation, and violence persist. Multi-generational patrilineal joint families have been the norm in India, though nuclear families are becoming common in urban areas. A very large majority of Indians have their marriages arranged by their parents or family elders. Marriage is thought to be for life; and the divorce rate is extremely low, less than one in a thousand.
=== With drugs === Lipoatrophy is the localised loss of fat in tissue. It is common in diabetics who use conventional insulin injection treatment. In 1949, a much more pure form of insulin was, instead of causing lipoatrophy, shown to regenerate the localised loss of fat after injections in to diabetics. In 1984, it was shown that different insulin injections have different regenerative responses with regards to creating skin fats in the same person. It was shown in the same body that conventional forms of insulin injections cause lipoatrophy and highly purified insulin injections cause lipohypertrophy. In 1976, the regenerative response was shown to work in a non-diabetic after a 3 × 3 cm lipoatrophic arm scar was treated with pure monocomponent porcine soluble insulin. A syringe injected insulin under the skin equally in the four quadrants of the defect. To layer four units of insulin evenly into the base of the defect, each quadrant of the defect received one unit of insulin three times a day, for eighty-two days. After eighty-two days of consecutive injections the defect regenerated to normal tissue. In 2016, scientists could transform a skin cell into any other tissue type via the use of drugs. The technique was noted as safer than genetic reprogramming which, in 2016, was a concern medically. The technique, used a cocktail of chemicals and enabled efficient on site regeneration without any genetic programming. In 2016, it was hoped to one day use this drug to regenerate tissue at the site of tissue injury.
Sources: en.wikipedia.org
=== Mortality risk === A 2012 study found a significantly lower ischemic heart disease mortality (-29%) and overall cancer incidence (-18%) in vegetarians in comparison to nonvegetarians. A 2017 review found a lower mortality (−25%) from ischemic heart disease.
On April 1, 2008, Pizza Hut in America sent emails to customers advertising their pasta items. The email (and similar advertising on the company's website) stated: "Pasta so good, we changed our name to Pasta Hut!" The name change was a publicity stunt held on April Fools' Day, extending through the month of April, with the company's Dallas headquarters changing its exterior logo to Pasta Hut. This name change was also used to promote the new Tuscani Pasta line and the new Pizza Hut dine-in menu. The first Pasta Hut advertisement showed the original Pizza Hut restaurant being imploded and re-created with a "Pasta Hut" sign. A version of this stunt was re-created by Pizza Hut's UK operation later that year in October 2008, which included ten locations in London temporarily taking on new "Pasta Hut" signage. Pizza Hut UK's chief executive at the time has insisted that this was solely intended as a "PR exercise" and the chain never planned on permanently changing its name in the UK or elsewhere.
Kopeček, "Super-Resolution Imaging and Quantitative Analysis of Membrane Protein/Lipid Raft Clustering Mediated by Cell Surface Self-Assembly of Hybrid Nanoconjugates". ChemBioChem 16, 1725–1729 (2015) R. Zhang, J. Yang, M. Sima, Y. Zhou, J. Kopeček, "Sequential Combination Therapy of Ovarian Cancer with Degradable N-(2-Hydroxypropyl)methacrylamide Copolymer Paclitaxel and Gemcitabine Conjugates". Proceedings of the National Academy of Sciences of the United States of America 111(33), 12181–12186 (2014) T.-W. Chu, J. Yang, J. Kopeček, "Anti-CD20 Multivalent HPMA Copolymer-Fab’ Conjugates for the Direct Induction of Apoptosis". Biomaterials 33, 7174–7181 (2012) H. Pan, J. Yang, P. Kopečková, J. Kopeček. :Backbone Degradable Multiblock N-(2-Hydroxypropyl)methacrylamide Copolymer Conjugates via Reversible Addition-Fragmentation Chain Transfer Polymerization and Thiol-ene Coupling Reaction". Biomacromolecules 12, 247–252 (2011) K. Wu, J. Liu, R.N. Johnson, J. Yang, J. Kopeček, "Drug-Free Macromolecular Therapeutics: Induction of Apoptosis by Coiled-Coil Mediated Crosslinking of Antigens on Cell Surface". Angewandte Chemie International Edition 49, 1451–1455 (2010) J. Kopeček, P. Kopečková, "HPMA Copolymers: Origins, Early Developments, Present, and Future". Advanced Drug Delivery Reviews 62, 122–149 (2010) J. Kopeček, "Hydrogels. From Soft Contact Lenses and Implants to Self-Assembled Nanomaterials". Journal of Polymer Science Part A: Polymer Chemistry 47, 5929–5946 (2009) J. Yang, C. Xu, C. Wang, J.
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.
It is the copper(II) complex of the tripeptide glycyl-L-histidyl-lysine, a sequence of three amino acids. The copper ion is held by the histidine imidazole, the terminal amino group, and an amide nitrogen. The bound form is distinct from the free peptide in charge, color, and stability.