This is a working overview of RP-HPLC, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-05-13. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| 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 |
Mechanistic accounts focus on how the complex delivers copper and how the released peptide interacts with the extracellular matrix. Copper is an essential cofactor for lysyl oxidase and other enzymes involved in collagen and elastin cross-linking, and GHK is one of several peptides able to carry the metal. Reported effects include altered gene expression in fibroblasts and changes in matrix metalloproteinase activity, although many of these findings come from cell culture rather than whole organisms. The relative contribution of the peptide backbone, the copper ion, and downstream copper metabolism is not fully resolved.
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.
Handling practices for the solid material emphasise low temperature and dryness. The lyophilised or powdered form is typically kept at refrigerator or freezer temperatures together with a desiccant. Working solutions are often prepared fresh, because repeated freeze-thaw cycles and extended storage may alter the complex. Glass or inert plastic containers are preferred over materials that could leach metal ions into the preparation. Such practices follow general peptide conventions rather than substance-specific regulations.
Analytical verification commonly relies on high-performance liquid chromatography for purity assessment and mass spectrometry for identity confirmation. Spectroscopic methods such as UV-visible absorption and electron paramagnetic resonance can probe the metal centre itself, since the d9 configuration of copper(II) produces characteristic signals. Elemental analysis or plasma-based techniques quantify copper content. Because each method reports a different aspect of the same sample, purity figures are most meaningful when the technique and its detection wavelength are stated alongside the value.
Stability of the complex in solution depends on pH, temperature, and the presence of competing ligands. It is generally described as more resistant to breakdown than the metal-free chain, since coordination reduces susceptibility to enzymatic attack. Oxidation and hydrolysis can nevertheless proceed over time in aqueous media. Storage guidance in laboratory settings commonly involves refrigeration, protection from light, and avoidance of strongly alkaline conditions. Published data on long-term behaviour vary considerably and depend on the specific matrix.
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 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.
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.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and copper(II). The peptide sequence consists of glycine, histidine, and lysine, and its imidazole and amino groups provide binding sites for the metal ion. In the complex, copper is held through nitrogen donors from the histidine side chain, the N-terminal amine, and deprotonated amide nitrogens. The resulting compound is intensely blue and water-soluble. It occurs naturally in human plasma, saliva, and urine at low concentrations.
== Implementation == The ceasefire took effect on 16–17 April 2026, following continued exchanges of fire in the hours leading up to its implementation. Israeli officials stated that forces would remain deployed inside southern Lebanon during the truce. Hezbollah, while not formally part of the agreement, indicated it would respond to any violations, raising concerns about the stability of the ceasefire. Reports of violations and continued tensions emerged shortly after the ceasefire began, with both sides accusing each other of breaches. Lebanese officials and allied groups warned displaced civilians not to return immediately due to ongoing uncertainty and security risks.
Earthworms exhibit an externally segmented tube-within-a-tube body plan with corresponding internal segmentations, and usually have setae on all segments. They have a double fluid transport system made of coelomic fluid that moves within the fluid-filled coelom and a simple, closed circulatory system, and respire (breathe) via cutaneous respiration. As soft-bodied invertebrates, they lack a true skeleton, but their structure is maintained by fluid-filled coelom chambers that function as a hydrostatic skeleton. Earthworms have a central nervous system consisting of two ganglia above the mouth, one on either side, connected to an axial nerve running along its length to motor neurons and sensory cells in each segment. Large numbers of chemoreceptors concentrate near its mouth. Circumferential and longitudinal muscles edging each segment let the worm move. Similar sets of muscles line the gut tube, and their actions propel digested food toward the worm's anus. Most earthworms are hermaphrodites: each worm carries male and female reproductive organs and genital pores. When mating, two individual earthworms will exchange sperm and fertilize each other's ova. However, many earthworm species are parthenogenetic, in particular in the Lumbricidae family (e.g. the test worm Eisenia fetida).
=== Smuggling and black-market activity === Smuggling of subsidized goods, such as wheat and other food staples, is common in Iran due to price discrepancies between Iran and its neighboring countries. Traders profit from exporting these goods illegally, reducing domestic availability and inflating prices. This problem is compounded by insufficient enforcement and border control, allowing such activities to thrive.
== Personal life == Sherman met and married Hildegard Schroeder while they were both graduate students at the University of Iowa, and they had three children: Karen, Marc, and Keith. In addition to his professional activities, he has participated in organizations such as the Boy Scouts of America, the Jewish War Veterans organization, and the Lions Club. Sherman died on December 1, 2023, at the age of 98.
== Background == Descriptions of rejuvenation and immortality remedies are often found in the writings of alchemists. But all those remedies did not allow even alchemists themselves to live longer than a hundred years. Though the average lifespan of people through the past millennia increased significantly, maximum lifespan almost did not change - even in ancient times there were fairly well and unbiasedly documented cases when some people lived for more than a hundred years (for example, Terentia who lived 103 or 104 years). While among the billions of people of the modern world, there is only one case of life over 120 years (Jeanne Calment, 122 years). The super-long lives of people that are mentioned in ancient books, apparently, are highly exaggerated, since archaeological data show that even the oldest of the ancient people lived no more than modern supercentenarians. In some cases the exaggeration, possibly, is not intentional but occurs due to errors in translation between languages and synchronization of chronological systems. The species limit of human life is estimated by scientists at 125–127 years, and even in the most ideal conditions a person will not live longer due to aging of the body. Some scientists believe that, even if medicine learns how to treat all major diseases, that will increase the average lifespan of people in developed countries by only about 10 years. For example, biogerontologist Leonard Hayflick stated that the natural average lifespan for humans is 92 years.
Sources: en.wikipedia.org
transgene Any gene or other segment of genetic material that has been isolated from one organism and then transferred either naturally or by any of a variety of genetic engineering techniques into another organism, especially one of a different species. Transgenes are usually introduced into the second organism's germ line. They are commonly used to study gene function or to confer an advantage not otherwise available in the unaltered organism.
Medical devices: Using single wall carbon nanotubes in medical devices results in no skin contamination, high flexibility, and softness, which are crucial for healthcare applications. Wearable electronics and 5G/6G communication: Electrodes with single wall carbon nanotubes (SWCNTs) exhibit excellent electrochemical properties and flexibility. Bitumen and asphalt: The world's first test section of road pavement with single wall carbon nanotubes (SWCNTs) showed a 67% increase in resistance to cracks and ruts, increasing the lifespan of the materials. Nanocomposites for aviation, automotive, and renewable energy markets: Modifying resin with just 0.02% single wall carbon nanotubes (SWCNTs) increases electrical conductivity by 276% without compromising the mechanical properties of fiber-reinforced polymers, also improving flexural properties and delaying thermal degradation. Additive manufacturing: single wall carbon nanotubes (SWCNTs) are mixed with a suitable printing medium or used as a filler material in the printing process, creating complex structures with enhanced mechanical and electrical properties. Utilizing carbon nanotubes as the channel material of carbon nanotube field-effect transistors. Using carbon nanotubes as a scaffold for diverse microfabrication techniques. Energy dissipation in self-organized nanostructures under the influence of an electric field. Using carbon nanotubes for environmental monitoring due to their active surface area and their ability to absorb gases. Jack Andraka used carbon nanotubes in his pancreatic cancer test.
==== Companion of the Order of St Michael and St George (CMG) ==== Jennifer Elizabeth Anderson, Director, Consular and Crisis, Foreign, Commonwealth and Development Office. For services to British Foreign Policy and to British Nationals Overseas. Zamir Nicholas Catasaras, Director General for Russia and Ukraine, Cabinet Office. For services to British Foreign Policy. Roger James Coventry, Criminal Justice Adviser. For services to Justice and Stability overseas. Colin Mark Evans, Director General, Foreign, Commonwealth and Development Office. For services to National Security. Dr Fiona Hill, Senior Fellow, Brookings Institution, Washington D.C., United States of America. For services to International Relations. Dr Rurik Miles Marsden, , Development Director, British Embassy Yangon, Myanmar. For services to International Development. Susanna Mary Davies Moorehead, lately Chair, Development Assistance Committee, The Organisation for Economic Co-operation and Development (OECD). For services to International Development and Diplomacy. Jane Anne Nelson, Director, Corporate Responsibility Initiative, Kennedy School of Government, Harvard University, United States of America. For services to Business and to Sustainability. Dr Sara Pantuliano, Chief Executive, ODI. For services to Peacebuilding, to Humanitarian Assistance and to International Development. Simon Penny, lately H.M. Trade Commissioner for the Middle East and Pakistan and H.M. Consul General to Dubai and the Northern Emirates. For services to International Trade and Investment.
== Proteomic profiling in disease detection == Proteomics profiling has been used in the discovery of biomarkers for diseases. A study conducted with the use of the Olink Proteomics Platform found that patients with glaucoma had differently expressed metabolic proteins, thus the potential of proteomics in early disease detection and development of a therapeutic strategy.
=== Next-generation matrix for compartmental models === In mathematical modelling of infectious disease, the dynamics of spreading is usually described through a set of non-linear ordinary differential equations (ODE). So there is always
Sources: en.wikipedia.org
10 October — Local authorities activate emergency operations centres in the Grey and Buller Districts in response to heavy rainfall, flooding and landslides. MetService issues heavy rain and wind warnings for that region. 11 October: The 2025 local elections, including local referendums on Māori wards and constituencies, conclude. 24 district and regional councils vote to remove their Māori wards and constituencies while 18 others vote to retain them. 14 October: Minister for Rail Winston Peters confirms that the New Zealand Government has contracted the Chinese state-owned shipyard COMEC to build two new rail-enabled Interislander ferries, which are expected to be delivered in 2029. The New Zealand Parliament passes legislation allowing radio and television stations to broadcast advertisements on Christmas Day, Good Friday, Easter Sunday and Anzac Day. Heavy rain causes flooding in the Waitomo and Ruapehu Districts in the central North Island, affecting several farms, roads, and some houses. Mayor of Waitomo John Robertson estimates the flood damage to be in the regions. 17 October: Highways reopen in the flood-stricken Waitomo and Ruapehu Districts. The New Zealand Professional Firefighters Union (NZPFU) held a one hour strike following the breakdown of pay negotiations broke down with Fire and Emergency New Zealand. The New Zealand Government reinstates several United Nations sanctions against Iran including asset freezes, travel bans and trade restrictions after Iran withdraws from the JCPOA agreements in September 2025.
Pratt (JP.1), it was entirely due to Collip's expertise that a far less toxic extract from that of Banting and Best's had been produced in just five weeks (p.288). Moreover, he was certain that, without Collip, the Toronto team would never have had an extract that was safe enough to administer to any human being. Also, according to Pratt (pp.286-288), the (pre-Collip) efforts of Banting and Best had been no improvement upon the work of George Ludwig Zuelzer fifteen years earlier: who, despite having been "on the right track" (in relation to recognizing the potential efficacy of a pancreatic extract in the treatment of diabetes mellitus) and, "even with the able assistance of the staff of the Physiological Institute of the University of Berlin as well as that of the trained chemists of the Schering Company over a period of four years [viz., prior to Zuelzer's 1907 publication], had been unable to lessen its toxicity sufficiently to have it employed clinically" (pp.286-288). By 22 February 1922, the Toronto team were reporting that "the effects observed in depancreatized animals have been paralleled in man", that the condition of seven patients had been "favourably influenced" by the daily injection of the extract, and that "the patients themselves report[ed] a subjective subjective sense of well being and increased vigor for a period following the [extract's] administration".
The NHS Grampian health board announcing it is to divert ambulance patients to hospitals outside its area because of "critical" pressure on its largest hospital. 29 November – Finlay MacDonald, who carried out a series of shootings on the Isle of Skye and the Scottish mainland, which included the fatal shooting of his brother-in-law, is sentenced to life imprisonment with a minimum term of 28 years. GP leaders in Scotland vote in favour of a motion to ballot workers on industrial action over pay, following what they describe as "years of disinvestment in general practice". 30 November – The Proclaimers perform at a memorial service for former first minister Alex Salmond, held at Edinburgh's St Giles' Cathedral.
In 1948, the Australian psychiatrist John Cade discovered the usefulness of lithium salts in treating mania while working at the Bundoora Repatriation Mental Hospital in Melbourne. He was injecting guinea pigs with urine extracts taken from manic patients in an attempt to isolate a metabolic compound which might be causing mental symptoms. Since uric acid in gout was known to be psychoactive, he needed soluble urate for a control. He used lithium urate, already known to be the most soluble urate compound, and observed that it caused the guinea pigs to become tranquil. Cade traced the effect to the lithium ion itself, and after Cade ingested lithium himself to ensure its safety in humans, he proposed lithium salts as tranquilizers. In 1949, he published his findings in the Medical Journal of Australia in a paper entitled "Lithium salts in the treatment of psychotic excitement". He soon succeeded in controlling mania in chronically hospitalized patients with lithium. This was one of the first successful applications of a drug to treat mental illness, and it opened the door for the development of medicines for other mental problems in the next decades. In 1950, one of Cade's first patients died of lithium toxicity after Cade had successfully treated him and released him from the hospital. Afterward, Cade abandoned the research of lithium and focused instead on testing other salts of rubidium, cerium, and strontium for their potential utility in psychiatry.
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.
The colour comes from electronic transitions in the coordinated copper(II) ion. Ligand field effects absorb part of the visible spectrum. A colourless or greenish sample may indicate degraded material.