If you have been reading about creatinine 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 2026-01-13. Numbers and descriptions here follow the published literature rather than marketing material.
Commercial creatine monohydrate is typically a white to off-white powder with low odor. It is commonly sold as a fine powder, micronized powder, or larger crystals, but these are physical forms of the same chemical. Purity grades vary, and products may contain small amounts of related substances such as creatinine, dicyandiamide, or moisture. The monohydrate is often selected for supplements and research because its production is well established and its behavior in water is predictable. Analytical certificates usually report assay, loss on drying, and heavy metals.
Creatine monohydrate is a crystalline compound formed from creatine and one water molecule in its solid lattice. Creatine itself is a nitrogen-containing organic acid involved in energy transfer in muscle and other tissues. The monohydrate form is the most common solid form used in research and commercial products because it is stable and easy to handle. The term "monohydrate" refers to the fixed one-to-one ratio of water to creatine in the crystal, not to moisture content. This distinction matters when comparing labels or calculating creatine content.
In chemical terms, creatine monohydrate is often described as N-(aminoiminomethyl)-N-methylglycine monohydrate, though nomenclature varies. Its solid state consists of zwitterionic creatine molecules linked with water through hydrogen bonding. The compound dissolves in water, but dissolution rate depends on particle size, temperature, and agitation. Once dissolved, the hydrate water becomes part of the solvent, leaving free creatine in solution. The monohydrate is not the same as creatine anhydrous, which lacks the water of crystallization and has a higher creatine fraction by mass.
In the body, creatine is obtained from dietary meat and fish and is also synthesized from arginine, glycine, and methionine. Muscle stores creatine and phosphocreatine, which participate in the rapid regeneration of adenosine triphosphate during short, intense activity. The monohydrate form is used in research because it is chemically defined, stable as a dry solid, and relatively inexpensive to produce. Questions remain about whether other creatine forms offer meaningful advantages in absorption or tissue retention, and findings vary across studies and populations.
Creatine monohydrate is a crystalline compound formed from creatine and one molecule of water. Creatine itself is a nitrogen-containing organic acid that occurs in vertebrate muscle and other tissues. The monohydrate designation refers to the water included in the crystal lattice, not to water added during manufacturing. Its chemical formula is commonly written as C4H9N3O2·H2O. The solid is typically a white, odorless powder with low solubility in water at room temperature. It is one of several creatine forms described in scientific and commercial literature.
The compound was identified in the nineteenth century after chemists isolated a nitrogenous substance from meat extracts. Later work established its role in muscle energy metabolism and its conversion to phosphocreatine. Chemical synthesis of creatine followed, and industrial production made the monohydrate widely available as a purified powder. Interest expanded in the late twentieth century when researchers began studying creatine supplementation and muscle physiology. Historical accounts sometimes differ on exact dates and attributions, but the broad sequence from tissue extracts to synthetic production is well documented.
| Property | Value | Notes |
|---|---|---|
| Chemical name | N-(aminoiminomethyl)-N-methylglycine monohydrate | Nomenclature varies across sources. |
| Common synonyms | Creatine hydrate; creatine monohydrate | “Monohydrate” specifies one water per creatine. |
| Appearance | White to off-white crystalline powder | Particle size and flowability vary by grade. |
| Solubility class | Soluble in water; slightly soluble in ethanol | Dissolution increases with temperature and stirring. |
| Typical storage | Tightly closed container at 15–25 °C | Protect from moisture and excessive heat. |
Storage recommendations generally emphasize a cool, dry place away from direct sunlight and strong oxidizers. Sealed containers limit humidity exchange, which helps prevent clumping and gradual conversion to creatinine. Long-term stability studies usually monitor appearance, moisture, and purity at intervals under defined temperature and humidity conditions. Accelerated tests at elevated temperature can reveal degradation pathways, but they do not perfectly predict room-temperature shelf life. Questions remain about how much creatinine formation is acceptable in different product categories and how packaging choices affect that rate over time.
Commercial creatine monohydrate is typically manufactured through chemical synthesis, often starting from sarcosine and cyanamide. The resulting material is crystallized, washed, and dried to a specified hydrate content. Finished lots are tested for identity, purity, moisture, and heavy metals before release. Because the compound can cyclize to creatinine under heat or prolonged storage in solution, manufacturers control temperature and humidity during processing. The solid itself is relatively stable when kept dry and sealed, but moisture uptake can cause caking and complicate accurate assay.
Analytical laboratories commonly identify creatine monohydrate by high-performance liquid chromatography with ultraviolet detection, often after dissolving the sample in water or dilute acid. Ion-exchange or reversed-phase columns separate creatine from creatinine and related guanidino compounds. Nitrogen content can be checked by Kjeldahl or combustion methods, while moisture is measured by Karl Fischer titration or loss on drying. These techniques give complementary views: chromatographic purity addresses related substances, whereas moisture and elemental data confirm hydrate stoichiometry. No single test defines quality by itself; a combination is used in specifications.
Identity and purity are commonly assessed by high-performance liquid chromatography, often with ultraviolet detection, and by spectroscopic techniques such as infrared or nuclear magnetic resonance. These methods can distinguish creatine from creatinine and detect related impurities. Moisture content may be measured by Karl Fischer titration or loss on drying. Particle size, bulk density, and heavy metal limits are additional quality parameters. Not every product is tested by every method, so specifications depend on the intended use and regulatory framework.
Solid creatine monohydrate is generally stable when kept dry and protected from extremes of heat and humidity. In the presence of moisture, it can gradually convert to creatinine, a cyclic dehydration product that has little value for phosphocreatine synthesis. Elevated temperatures and acidic conditions accelerate this conversion in solution. Because the reaction is slow in cool, dry storage, typical shelf lives are measured in years rather than weeks. Packaging that limits moisture and oxygen exposure helps maintain purity.
Recommended storage usually involves a sealed container kept at room temperature, away from direct sunlight and moisture. High humidity can cause caking, which changes flow properties and may complicate accurate weighing. Repeated opening of containers exposes the powder to air and moisture, so smaller aliquots can reduce handling effects. Storage temperature ranges are not absolute requirements; they reflect conditions that slow degradation and preserve consistent physical characteristics. Clean, dry tools help prevent contamination during sampling.
Handling practices aim to limit moisture uptake and thermal exposure. Containers should stay closed when not in use, and storage areas should avoid direct sunlight, strong heat, and high humidity. Caking can occur when powder absorbs water, even if the creatine itself has not fully degraded. Aqueous stock solutions are best prepared fresh when needed because they are less stable than the solid. Open questions include how different excipients, packaging materials, and climate conditions affect long-term stability across global supply chains.
Solid creatine monohydrate is relatively stable when kept dry and sealed, but heat and moisture accelerate its conversion to creatinine. This degradation involves intramolecular cyclization, a process that removes water and forms a less useful compound for phosphocreatine metabolism. Powder stored under cool, dry conditions can remain within specification for extended periods, though exact shelf life depends on packaging, humidity, and initial purity. Aqueous solutions degrade faster than dry powder, with pH and temperature influencing the rate. Because degradation is gradual, analytical testing is used to confirm potency at manufacture and during stability studies.
Quality control for creatine monohydrate typically combines identity, assay, and impurity tests. High-performance liquid chromatography with ultraviolet detection is common for separating creatine from creatinine and related substances. Nuclear magnetic resonance and infrared spectroscopy can confirm molecular structure, while titration may assess acid-base content. Moisture content, heavy metals, residual solvents, and microbial limits are checked according to applicable standards. These tests help distinguish compliant material from powders that have degraded, been diluted, or contain manufacturing residues.
Sourcing and verification of creatine monohydrate involve both manufacturing origin and third-party testing. Industrial production commonly starts with sarcosine and cyanamide, followed by crystallization to obtain the monohydrate. Some products are derived from animal sources, while others are synthesized from non-animal precursors. Certificates of analysis report assay, heavy metals, and microbial limits. Regulations differ by country: in the United States it is sold as a dietary supplement, whereas in the European Union it falls under food supplement rules.
In solid form, creatine monohydrate is relatively stable when kept dry and away from heat. Moisture and elevated temperatures promote cyclization into creatinine, a related compound with no role in the phosphagen system. Degradation accelerates in aqueous solution, where the conversion can occur within hours to days depending on pH and temperature. Manufacturers typically recommend storage in sealed containers at room temperature, with relative humidity below 50 percent. Long-term stability data for opened containers are limited.
Analytical methods for creatine monohydrate focus on identity, purity, and degradation products. High-performance liquid chromatography with ultraviolet detection is common, often at a wavelength near 210 nanometers. Titration and nuclear magnetic resonance spectroscopy can also quantify the parent compound. Pharmacopeial monographs specify tests for appearance, solubility, water content, and related substances, including creatinine. Purity values above 99 percent are typical for pharmaceutical-grade material, though supplement-grade products vary. Independent verification can detect label discrepancies.
MR-2034, or Mr-2034, also known as (–)-MR-2033, is a selective κ-opioid receptor (KOR) agonist of the benzomorphan family. Unlike other benzomorphan KOR agonists like cyclazocine and alazocine, MR-2034 does not also act on sigma receptors. In addition to the KOR, it has affinity for the μ-opioid receptor (MOR), but does not activate this receptor. The drug produces dose-dependent hallucinogenic and dysphoric effects in humans, as well as other effects such as dizziness, anxiety, and sedation. These effects can be blocked by the non-selective opioid receptor antagonist naloxone. The preceding findings led to the conclusion that the hallucinogenic and dysphoric effects of benzomorphans are mediated by the KOR rather than by sigma receptors. MR-2034 was first described in the scientific literature by 1975 and its hallucinogenic effects in humans were described in 1986.
== History == The first acknowledged case of obesity-related non-alcoholic fatty liver was observed in 1952 by Samuel Zelman. Zelman started investigating after observing a fatty liver in a hospital employee who drank more than twenty bottles of Coca-Cola a day. He then went on to design a trial for a year and a half on 20 people with obesity who did not have alcohol use disorder, finding that about half of them had substantially fatty livers. Fatty liver was, however, linked to diabetes since at least 1784 — an observation picked up again in the 1930s. Studies in experimental animals implicated choline inadequacy in the 1920s and excess sugar consumption in 1949. The name "non-alcoholic steatohepatitis" (NASH) was later defined in 1980 by Jurgen Ludwig and his colleagues from the Mayo Clinic to raise awareness of the existence of this pathology, as similar reports previously were dismissed as "patients' lies". This paper was mostly ignored at the time but eventually came to be seen as a landmark paper, and starting in the mid-1990s, the condition began to be intensively studied, with a series of international meetings being held on the topic since 1998. The broader NAFLD term started to be used around 2002. Diagnostic criteria began to be worked out, and in 2005 the Pathology Committee of the NIH NASH Clinical Research Network proposed the NAS scoring system. In 2023, a global consensus panel composed mostly of hepatology researchers and clinicians recommended a change of name to metabolic dysfunction–associated steatotic liver disease (MASLD).
=== Sedation === Since trazodone may impair the mental or physical abilities required for the performance of potentially hazardous tasks, such as operating an automobile or machinery, the patient should be cautioned not to engage in such activities while impaired. Compared to the reversible MAOI antidepressant drug moclobemide, more impairment of vigilance occurs with trazodone. Trazodone has been found to impair driving ability.
Sources told the Miami Herald that Qatar, which "has close ties to the Venezuelan government", had "played a key role as intermediary" between Maduro officials and siblings Delcy and Jorge Rodríguez in promoting Delcy and the unrelated Miguel Rodríguez Torres to lead a transition as "a 'more acceptable' alternative to Nicolás Maduro's regime", with the aim of "preserving political stability without dismantling the ruling apparatus". The Associated Press confirmed the report, and stated that an anonymous official said the proposal was that Maduro be replaced by Delcy through the end of his term in 2031; the AP reported that Washington "rejected the proposal because it continues to question the legitimacy of Maduro's rule". Maduro and Delcy Rodríguez labeled the information as fake news, with the latter saying the report was part of a psychological warfare operation.
As the nascent polypeptide elongates during proteosynthesis, it passes through the ribosomal tunnel, interacting with the tunnel walls, thus regulating the rate at which it passes through the tunnel. This in turn affect the rate of partial folding, which may already occur at this stage. Short stretches of alpha-helix may form in the inner part of the tunnel and tertiary structure may start forming in the wider tunnel vestibule. As the N-terminus reaches the tunnel exit and is processed by the ribosome-associated protein biogenesis factors, the tertiary structure formed in the tunnel may partially refold. The folding is then completed when the C-terminus is released from the PTC and the protein escapes the tunnel.
Sources: en.wikipedia.org
The Environmental Investigation Agency in 2016 estimated that 34 species of fish were being traded on the wider Chinese fish maw market. Sciaenidae (croakers/drums) are typically the most valued, due to their similarity to the historically prized and critically endangered Chinese bahaba. Other targeted fishes include eels, stonefishes, lates perch, groupers, threadfins and sturgeon.
==== Antidepressants ==== Alaproclate (GEA-654) Centpropazine Cericlamine (JO-1017) Femoxetine (Malexil; FG-4963) Ifoxetine (CGP-15210) Omiloxetine Panuramine (WY-26002) Pirandamine (AY-23713) Seproxetine ((S)-norfluoxetine)
=== October === 1 October – PPE Medpro is ordered to pay back £122m to the government after supplying non-compliant medical gowns during the COVID-19 pandemic. 2 October – Former Conservative MP Sarah Atherton joins Reform UK and says she wants to stand in the 2026 Senedd election. Reform UK-led Nottinghamshire County Council partially lift the ban they imposed on the Nottingham Post in response to a request to lift it in full from a law firm representing the publishers. Kemi Badenoch pledges to repeal the Climate Change Act 2008. 3 October – Dame Sarah Mullally is named as the first female Archbishop of Canterbury, replacing Justin Welby following his resignation. Zack Polanski makes his keynote speech as leader of the Green Party of England and Wales at their annual conference. Shabana Mahmood calls Pro-Palestinian protests "un-British" following the 2025 Manchester synagogue attack. Michelle Mone, Baroness Mone says she has no wishes to return to the House of Lords. 4 October – The 2025 Conservative Party Conference begins in Manchester. London Assembly member Keith Prince defects from the Conservative Party to Reform UK. 5 October – The Conservatives say they would task officials with deporting 750,000 migrants over five years if they form the next government. 7 October – The Guardian publishes video footage of Robert Jenrick, the Shadow Justice Secretary, describing the Handsworth area of Birmingham as "one of the worst-integrated places" in the UK during an after dinner speech recorded in March. 20 Conservative councillors defect to Reform UK.
=== Effects on ozone layer === Sulfur dioxide aerosols in the stratosphere can contribute to ozone depletion in the presence of chlorofluorocarbons and other halogenated ozone-depleting substances. The effects of volcanic eruptions containing sulfur dioxide aerosols on the ozone layer are complex, however. In the absence of anthropogenic or biogenic halogenated compounds in the lower stratosphere, depletion of dinitrogen pentoxide in the middle stratosphere associated with its reactivity to the aerosols can promote ozone formation. Injection of sulfur dioxide and large amounts of water vapor into the stratosphere following the 2022 eruption of Hunga Tonga-Hunga Haʻapai resulted in altered atmospheric circulation that promoted a decrease in ozone in the southern latitudes but an increase in the tropics. The additional presence of hydrochloric acid in eruptions can result in net ozone depletion.
Since the beginning of the 21st century, fast food has been criticized for its animal welfare record, its links to obesity and its environmental impact. Eric Schlosser's book Fast Food Nation (2002) and Morgan Spurlock's film Super Size Me (2004) reflected these concerns. Since 2003, People for the Ethical Treatment of Animals (PETA) has protested KFC's choice of poultry suppliers worldwide. The exception is KFC Canada, which signed an agreement pledging to only use "animal-friendly" suppliers. President of KFC's US division Gregg Dedrick said PETA mischaracterized KFC as a poultry producer rather than a purchaser of chickens. In 2008, Yum! stated: "[As] a major purchaser of food products, [Yum!] has the opportunity and responsibility to influence the way animals supplied to us are treated. We take that responsibility very seriously, and we are monitoring our suppliers on an ongoing basis." In 2006, Greenpeace accused KFC Europe of sourcing the soya bean for its chicken feed from Cargill, which had been accused of clearing large swathes of the Amazon rainforest in order to grow the crop. In 2010, according to The Guardian, "in the US where fried chicken remains closely associated with age-old racist stereotypes about black people in the once segregated south", KFC Australia aired the 30-second promotion on television named "KFC's cricket survival guide" which shows a white cricket fan surrounded by black fans from the opposing team.
Sources: en.wikipedia.org
=== G protein-coupled receptor inverse agonists === Two known endogenous inverse agonists are the Agouti-related peptide (AgRP) and its associated peptide Agouti signalling peptide (ASIP). AgRP and ASIP appear naturally in humans and bind melanocortin receptors 4 and 1 (Mc4R and Mc1R), respectively, with nanomolar affinities. The opioid antagonists naloxone and naltrexone act as neutral antagonists of the mu opioid receptors under normal conditions, but as inverse agonists when chronic exposure to opioids has increased the basal activity of the mu opioid receptors. 6α-naltrexo, 6β-naltrexol, 6β-naloxol, and 6β-naltrexamine acted neutral antagonists regardless of opioid binding and caused significantly reduced withdrawal jumping when compared to naloxone and naltrexone. Nearly all antihistamines acting at H1 receptors and H2 receptors have been shown to be inverse agonists. The beta blockers carvedilol and bucindolol have been shown to be low level inverse agonists at beta adrenoceptors.
Hormone receptor proteins bind to a hormone as a result of an accumulation of weak interactions. Because of the relatively large size of enzymes and receptors, the large amount of surface area provides the basis for these weak interactions to occur. This binding is actually highly specific because of the complementarity of these interactions between polar, non-polar, charged, neutral, hydrophilic, or hydrophobic residues. Upon binding, the receptor often undergoes a conformational change and may bind further, signaling ligands to activate a signaling pathway. Because of these highly specific and high affinity interactions between hormones and their receptors, very low concentrations of hormone can produce significant cellular response. Receptors can have various different structures depending on the function of the hormone and the structure of its ligand. Therefore, hormone binding to its receptor is a complex process that can be mediated by cooperative binding, reversible and irreversible interactions, and multiple binding sites.
Cyclopia intermedia, known as 'bergtee' (mountain tea), found between Port Elizabeth and the edge of the Langkloof Cyclopia genistoides, known as 'kustee' (coastal tea), found mostly in the Western Cape near Yzerfontein and Darling and also thriving in the South Cape if cultivated Cyclopia maculata, grown in the Outeniqua area near George Cyclopia sessiliflora, known as 'Heidelberg-tee', named after the town Heidelberg in South Africa, where it grows in the local mountain range Cyclopia subternata, known as 'vleitee' (marshland tea) or 'valleitee' (valley tea) Cyclopia longifolia Some species can be cultivated whereas others have resisted all attempts at cultivation and must be harvested in the wild. It is not always easy to discover what the seeds need to enable them to germinate; some kinds bear elaiosomes and might be dependent on the services of particular ants or birds. Cyclopia intermedia (mountain tea) is one of the teas that is harvested in the Kouga mountains where it grows naturally. Mountain tea regenerates within three years after harvesting or devastation by fire; consequently less than one third of the mountain yield is available for harvesting each year by rotation. Mountain tea and valley tea flower in September/October whereas coastal tea flowers in May/June.
Homo sapiens FGFR1 oncogene partner 2 (FGFR1OP2), transcript variant 1, mRNA (NCBI) Homo sapiens FGFR1 oncogene partner 2 isoform 1 (NCBI) FGFR1OP2 human gene location in the UCSC Genome Browser. FGFR1OP2 human gene details in the UCSC Genome Browser.
Harry Emerson. For services to the community in Stockton-on-Tees, Cleveland. Elizabeth Margaret Evans. For services to the community, particularly Disabled People, in Llanelli, Dyfed. Shirley Everett, Newsvendor. For services to the community in Westminster, London. Doris Mabel Eves. For services to the Citizens' Advice Bureau in Farnborough, Hampshire. George Fitton Exley, Honorary Secretary, Scarborough Lifeboat Station. For services to the Royal National Lifeboat Institution. Ellen Branker Farmer, President, Old Paisley Society. For services to Conservation. Margaret Winifred Farmer. For services to the Royal British Legion in Sevenoaks, Kent. Eric Arnold Faux. For services to disabled people in Birmingham Valerie Ann Fea, lately Executive Secretary, the School Library Association. For services to Librananship and to Young People. Heather Duncan Findlay, Local Officer 2, the Benefits Agency, Department of Social Security. Nina Mary Fineron, lately Typist, Department of Social Security. Isabel H. Finlay, lately Chiropodist, Glasgow. For services to Health Care. Millar Henry Finlay, Divisional Officer, (Special Constabulary), Flintshire Division, North Wales Police. For services to the Police. Olwen Finlay. For services to Physiotherapy. Evelyn May Fisher. For services to Netball in Coventry. Myra Caroline Fisher. For services to the community in Paulsgrove, Portsmouth, Hampshire. Bernard Joseph Fitzsimmons. For public service. Michael Robert Flegg, Catering Manager, Nottingham City Hospital. For services to Health Care. Iris Mary Fletcher.
Sources: en.wikipedia.org
It is a solid form of creatine that contains one water molecule per creatine molecule in the crystal lattice. The hydrate water is part of the crystal structure rather than loose moisture. The term is often used for the common crystalline powder grade.
Creatine anhydrous lacks the water of crystallization and therefore contains a higher creatine fraction by mass. The monohydrate is more common in commerce and research because it is stable and easy to handle. The two forms are not identical in solid state, though both yield creatine when dissolved.
Creatine is the base molecule, while creatine monohydrate is a hydrate of that molecule. Once dissolved, the hydrate water becomes part of the solvent and free creatine is present. In casual usage the names are often shortened to creatine, but the solid forms differ.
It is a crystalline form of creatine that contains one water molecule per creatine molecule. The compound occurs naturally in muscle tissue and is also produced synthetically for research and consumer products. The monohydrate label describes the solid's hydration state.