If you have been reading about phosphocreatine 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.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
In animals, creatine is synthesized mainly in liver, kidney, and pancreas from arginine, glycine, and methionine. The first committed step transfers a guanidino group from arginine to glycine, forming guanidinoacetate. Subsequent methylation by S-adenosylmethionine yields creatine. Dietary sources include meat and fish; endogenous synthesis supplies part of the body pool. Most creatine is stored in skeletal muscle, where it is converted to phosphocreatine and participates in rapid regeneration of adenosine triphosphate during short, intense activity.
Commercial creatine products appear in several forms, including monohydrate, hydrochloride, citrate, nitrate, and ethyl ester. Creatine monohydrate is the most studied form and serves as a reference material in comparative research. Different forms vary in solubility, pH, and water content, but they share creatine as the active moiety after dissolution. Claims that one form is uniformly superior remain debated, and study designs often differ in population, exercise protocol, and outcome measures. Purity and hydration state are central to interpreting product labels.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | 15–25 °C | Cool, dry, away from moisture |
| Relative humidity | < 50% | High humidity promotes degradation |
| Primary degradation product | Creatinine | Formed via cyclization, especially in solution |
| Common analytical method | HPLC-UV | Often at 210 nm; also titration or NMR |
| Shelf life (solid) | 2–3 years | When kept sealed and dry; varies by manufacturer |
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.
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.
In the body, creatine is synthesized from arginine, glycine, and methionine, mainly in the liver and kidneys, and is also obtained from foods such as meat and fish. About 95% of body creatine is stored in skeletal muscle, where a fraction is phosphorylated to phosphocreatine. Phosphocreatine serves as a rapid reserve of high-energy phosphate for short bursts of ATP regeneration. The monohydrate form supplies creatine after dissolution and absorption, but it is not itself the active phosphorylated species.
Creatine was first identified in skeletal muscle extracts in the nineteenth century, and its role in phosphagen energy buffering was clarified in the twentieth century. The monohydrate salt became widely studied after methods for inexpensive synthesis and crystallization were developed. Modern research examines its effects on muscle energetics, recovery, and cognitive performance under specific conditions. Findings vary with population, exercise protocol, baseline creatine status, and measurement method. Studies often compare supplementation with placebo during controlled training or testing schedules.
Creatine monohydrate is a hydrated form of creatine, a nitrogen-containing compound involved in cellular energy metabolism. Its molecular formula is C4H9N3O2·H2O, with a molar mass around 149.15 g/mol. The monohydrate is the most common solid form used in research and commercial settings because it crystallizes readily and remains stable under ordinary conditions. The term monohydrate indicates one water molecule per creatine molecule in the crystal lattice. It appears as a white crystalline powder with low odor.
== Biodistribution and mechanisms of action == Lithium compartmentalization was studied in 11 biosubstrates of rats when lithium ascorbate was taken at a dose of 1000 mg/kg. As part of a tubeless analysis of the dynamics of concentrations in whole blood, the following values of the pharmacokinetic parameters of lithium ascorbate were obtained: Cmax=50.59 µg/l, tmax=1.50 h, Clast=33.7 µg/l, AUCt=1750 µg/l*h, MRTt=22.9 h, Lz=0.005 1/h, T1/2=141 h, CL=0.029 l/h, Vd=5.9 l. Multichamber pharmacokinetic analysis showed that the stabilization of lithium levels in the blood is maintained by a special "depot" of lithium, apparently consisting of the aorta, femur and brain. Application of the method of functional linkage analysis suggested that the targeted accumulation of ascorbate anion in cells is due to the activity of vitamin C transport proteins SLC23A1, SLC23A2, SLC23A3. At the same time, lithium ions and ascorbate exhibit a synergistic effect. The main effects of lithium include the support of normal excitability central nervous system: by preventing excessive concentration of norepinephrine, regulation of sodium concentration in muscle cells (which is important for the tone of blood vessels), sensitivity of neurons to dopamine, which reduces the negative impact of stress.
==== Cyclin E ==== As processes in cell cycle progression are the most fundamental processes for cellular growth and differentiation, and are the most common to be altered in human carcinomas, it is expected for cell cycle-regulatory proteins to be under tight regulation. The level of cyclins, as the name suggests, is high only at certain a time point during the cell cycle. This is achieved by continuous control of cyclins or CDKs levels through ubiquitylation and degradation. When cyclin E is partnered with CDK2 and gets phosphorylated, an SCF-associated F-box protein Fbw7 recognizes the complex and thus targets it for degradation. Mutations in Fbw7 have been found in more than 30% of human tumors, characterizing it as a tumor suppressor protein.
Culver Franchising System, LLC, doing business as Culver's, is an American regional fast-casual restaurant chain. The company was founded in 1984 by George, Ruth, Craig, and Lea Culver. The first location opened in Sauk City, Wisconsin, on July 18, 1984, under the name "Culver's Frozen Custard and ButterBurgers". The privately held company is headquartered in Prairie du Sac, Wisconsin. The chain operates primarily in the Midwestern United States, and has a total of 1,000 restaurants in 26 states as of April 2025.
== Cost-of-living == Mercer Cost of Living Survey 2016: Bangkok ranked 74 of 209 cities (1=most expensive; 209=least expensive). The Mercer survey measures the comparative cost of more than 200 items in each city, including housing, transportation, food, clothing, household goods, and entertainment. It is designed for multinationals and governments to use in determining compensation for expatriate employees. Cost of Living Index 2015 mid-year: Thailand ranked 89 of 125 nations (1=most expensive; 125=least expensive).
Sources: en.wikipedia.org
== Commercialization == 1-MNA has been approved for use in food products in the form of 1-MNA chloride. The approval process in the European Union was successfully completed by PHARMENA SA. In 2017, the European Food Safety Authority (EFSA) confirmed the safety of 1-MNA chloride in food supplements, leading to its authorization in 2018 under EU Regulation 2018/1123. 1-MNA chloride is currently used in dietary supplements. Other chemical forms of 1-MNA are not currently allowed on the market as food.
Somalia contains a variety of mammals due to its geographical and climatic diversity. Wildlife still occurring includes cheetah, lion, reticulated giraffe, baboon, serval, elephant, bushpig, gazelle, ibex, kudu, dik-dik, oribi, Somali wild ass, reedbuck and Grévy's zebra, elephant shrew, rock hyrax, golden mole and antelope. It also has a large population of the dromedary camel. Somalia is home to around 727 species of birds. Of these, eight are endemic, one has been introduced by humans, and one is rare or accidental. Fourteen species are globally threatened. Birds species found exclusively in the country include the Somali pigeon; Alaemon hamertoni (Alaudidae), Lesser Hoopoe-Lark; Heteromirafra archeri (Alaudidae), Archer's Lark; Mirafra ashi, Ash's Bushlark; Mirafra somalica (Alaudidae), Somali Bushlark; Spizocorys obbiensis (Alaudidae), Obbia Lark; Carduelis johannis (Fringillidae); and Warsangli Linnet. Somalia's territorial waters are prime fishing grounds for highly migratory marine species, such as tuna. A narrow but productive continental shelf contains several demersal fish and crustacean species. Fish species found exclusively in the nation include Cirrhitichthys randalli (Cirrhitidae), Symphurus fuscus (Cynoglossidae), Parapercis simulata OC (Pinguipedidae), Cociella somaliensis OC (Platycephalidae), and Pseudochromis melanotus (Pseudochromidae). There are roughly 235 species of reptiles. Of these, almost half live in the northern areas.
According to the marketeer, the old name "McDonald's" will soon disappear from the lexicon of the Russian consumers, and, to not pronounce the long phrase, clients of the chain will make up their own. On 13 June, various messages appeared claiming that the logo of Vkusno i tochka is a lazy alteration of a Portuguese pet food brand "Matosmix". On 15 June, the director of a fast food chain known as "Food, full stop" (Russian: Еда и точка) in Primorsky Krai, Sergei Ponkratov, accused the new chain of plagiarism and decided to sue it, demanding a change of the name. He claims that the Vkusno i tochka brand clearly intersects with and deprives his trademark, which has been operating since 2018, of uniqueness and recognizability.
Sources: en.wikipedia.org
Natural tantalum (73Ta) consists of two isotopes: observationally stable 181Ta (99.988%) and 180mTa (0.012%). There are also 35 known artificial radioisotopes, the longest-lived of which are 179Ta with a half-life of 1.82 years, 182Ta with a half-life of 114.74 days, 183Ta with a half-life of 5.1 days, and 177Ta with a half-life of 56.46 hours. All other isotopes have half-lives under a day, most under an hour. There are also numerous isomers, the most stable of which (other than 180mTa) is 182m2Ta with a half-life of 15.8 minutes. All isotopes and nuclear isomers of tantalum are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed. Tantalum has been proposed as a "salting" material for nuclear weapons (cobalt is another, better-known salting material). A jacket of tantalum, irradiated by the intense high-energy neutron flux of the weapon, would be transmuted into the radioactive isotope 182Ta, producing about 1.12 MeV of gamma radiation per decay and significantly increasing the radioactivity of the weapon's fallout for months. Such a weapon is not known to have ever been built, tested, or used.
== Industrial radioactive tracer uses == Used for the first time in 1951 to localize leaks in a drinking water supply system of Munich, Germany, iodine-131 became one of the most commonly used gamma-emitting industrial radioactive tracers, with applications in isotope hydrology and leak detection. Since the late 1940s, radioactive tracers have been used by the oil industry. Tagged at the surface, water is then tracked downhole, using the appropriated gamma detector, to determine flows and detect underground leaks. I-131 has been the most widely used tagging isotope in an aqueous solution of sodium iodide. It is used to characterize the hydraulic fracturing fluid to help determine the injection profile and location of fractures created by hydraulic fracturing.
Optical storage uses lasers to store and retrieve data. Recordable CDs, DVDs, and Blu-ray Discs are commonly used with personal computers and are generally cheap. The capacities and speeds of these discs have typically been lower than hard disks or tapes. Advances in optical media may shrink that gap in the future. Potential future data losses caused by gradual media degradation can be predicted by measuring the rate of correctable minor data errors, of which consecutively too many increase the risk of uncorrectable sectors. Support for error scanning varies among optical drive vendors. Many optical disc formats are WORM type, which makes them useful for archival purposes since the data cannot be changed in any way, including by user error and by malware such as ransomware. Moreover, optical discs are not vulnerable to head crashes, magnetism, imminent water ingress or power surges; and, a fault of the drive typically just halts the spinning. Optical media is modular; the storage controller is not tied to media itself like with hard drives or flash storage (→flash memory controller), allowing it to be removed and accessed through a different drive. However, recordable media may degrade earlier under long-term exposure to light. Some optical storage systems allow for cataloged data backups without human contact with the discs, allowing for longer data integrity. A French study in 2008 indicated that the lifespan of typically-sold CD-Rs was 2–10 years, but one manufacturer later estimated the longevity of its CD-Rs with a gold-sputtered layer to be as high as 100 years.
=== Helmholtz === The model dubbed the 'electric double layer' was first introduced by Hermann von Helmholtz. It assumes that a solution is only composed of electrolytes, no reactions occur near the electrode which could transfer electrons, and that the only Van der Waals interactions are present between the ions in solution and the electrode. These interactions arise only due to the charge density associated with the electrode which arises from either an excess or deficiency of electrons at the electrode's surface. To maintain electrical neutrality the charge of the electrode will be balanced by a redistribution of ions close to its surface. The attracted ions thus form a layer balancing the electrode's charge. The closest distance an ion can come to the electrode will be limited to the radius of the ion plus a single solvation sphere around an individual ion. Overall, two layers of charge and a potential drop from the electrode to the edge of the outer layer (outer Helmholtz Plane) are observed. Given the above description, the Helmholtz model is equivalent in nature to an electrical capacitor with two separated plates of charge, for which a linear potential drop is observed at increasing distance from the plates. The Helmholtz model, while a good foundation for the description of the interface does not take into account several important factors: diffusion/mixing in solution, the possibility of adsorption on to the surface and the interaction between solvent dipole moments and the electrode.
Sources: en.wikipedia.org
Yes, especially when exposed to moisture or heat, where it converts to creatinine. In dry, sealed containers at room temperature, degradation is slow and the product may remain within specification for two to three years.
Common methods include high-performance liquid chromatography, titration, and nuclear magnetic resonance spectroscopy. These techniques quantify the parent compound and detect related substances such as creatinine.
Keep the powder in a tightly sealed container in a cool, dry place, ideally between 15 and 25 degrees Celsius with low humidity. Avoid storing aqueous solutions for extended periods because degradation occurs faster in solution.
Creatine is the base compound, while creatine monohydrate includes one water molecule per creatine molecule in its crystal structure. The monohydrate form is common in supplements and analytical standards. The body uses creatine itself after the water is removed or dissociated.