A practical reference on HPLC: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-01-10. Anything still debated is marked as such rather than presented as settled.
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.
Dry creatine monohydrate is generally stable when kept sealed and protected from heat and moisture. In solution, however, creatine undergoes a slow cyclization to creatinine, a related compound with no role in phosphocreatine storage. The rate of this conversion increases with temperature and is influenced by pH. Because creatinine is a common impurity in liquid or poorly stored products, analytical testing often measures both compounds. The crystalline monohydrate is less prone to degradation than aqueous preparations, though caking can occur if moisture enters the container.
Laboratory analysis of creatine monohydrate typically uses high-performance liquid chromatography to separate creatine from creatinine and other impurities. Detection may be ultraviolet, refractive index, or mass spectrometric, depending on the laboratory's equipment and the required sensitivity. Nuclear magnetic resonance spectroscopy can quantify the main component and identify related substances. Water content is measured by Karl Fischer titration, which is important because the monohydrate has a defined theoretical hydration level. Heavy metals, residual solvents, and microbial limits are also checked in quality control programs.
Commercial creatine monohydrate is produced mainly by chemical synthesis rather than extraction from animal tissue. Suppliers provide a certificate of analysis listing assay, water content, and impurity limits, and some products undergo third-party testing. Verification of identity can use infrared or Raman spectroscopy alongside chromatographic methods. Storage recommendations generally call for a cool, dry place and a tightly closed container to limit moisture uptake. Open questions include how packaging, flavoring agents, and long-term storage affect the stability of finished products.
| Property | Value | Notes |
|---|---|---|
| Chemical formula | C4H9N3O2·H2O | Monohydrate includes one water molecule per creatine molecule |
| Molar mass | 149.15 g/mol | Value for the monohydrate; anhydrous creatine is about 131.13 g/mol |
| Appearance | White crystalline powder | Odorless or nearly odorless in purified form |
| Solubility in water | About 13 g/L at 25 °C | Solubility increases with temperature and varies with pH |
| Common synonyms | Creatine hydrate; N-(aminoiminomethyl)-N-methylglycine | Monohydrate distinguishes it from anhydrous creatine |
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.
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 when one molecule of creatine binds with one molecule of water. Creatine itself is a nitrogen-containing organic acid involved in cellular energy transfer, particularly in muscle and nerve tissue. The monohydrate form is the most common solid form used in research and commercial products because it is relatively stable and easy to handle. Its molecular formula is C4H9N3O2·H2O, and its molar mass is about 149.15 grams per mole.
In the human body, creatine is synthesized mainly in the liver and kidneys from the amino acids glycine, arginine, and methionine. Dietary sources include meat, fish, and other animal tissues, which supply preformed creatine. Because plant foods contain little or no creatine, dietary intake varies widely among populations. The compound is stored largely in skeletal muscle, where it is converted to phosphocreatine and used to regenerate adenosine triphosphate during short bursts of activity.
Creatine monohydrate is one of several solid forms of creatine described in the literature. Other forms include anhydrous creatine, creatine hydrochloride, and creatine ethyl ester, each with different solubility and stability characteristics. The monohydrate is distinct from creatinine, a spontaneous breakdown compound that forms when creatine loses water and cyclizes. Commercial descriptions sometimes use synonyms such as methylguanidoacetic acid or N-(aminoiminomethyl)-N-methylglycine, which refer to the same base molecule. These names appear in chemical databases and product labels.
In aqueous solution, creatine monohydrate undergoes a slow conversion to creatinine, a cyclized degradation product. This reaction is pH- and temperature-dependent, and it proceeds faster in warm or alkaline conditions. Because the conversion is gradual, analytical measurements of creatine in solution must account for time and storage history. The equilibrium favors creatinine more strongly at higher temperatures, which is relevant to sample handling in laboratories and to beverage formulations. Refrigeration slows but does not entirely stop this process.
Quality assessment of creatine monohydrate typically uses high-performance liquid chromatography to separate creatine from creatinine and other impurities. Other methods include nuclear magnetic resonance spectroscopy, titration, and infrared spectroscopy for identity confirmation. Purity is often reported as a percentage of the labeled compound on a dry basis, while moisture content is measured separately. Because different analytical methods have different selectivity, comparing purity values across sources requires attention to the method and sample preparation.
In dry solid form, creatine monohydrate is relatively stable when protected from moisture and heat. The crystal lattice includes water, and exposure to high humidity can cause caking or gradual changes in powder flow. Elevated temperatures may accelerate decomposition, particularly if moisture is present. Studies generally report that sealed, dry material retains acceptable purity for extended periods, although exact shelf life depends on packaging and storage conditions. Light exposure is not usually considered a major factor for this compound.
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.
Creatine monohydrate is the hydrated form of creatine, a nitrogen-containing organic acid involved in cellular energy transfer. Its molecular formula is C4H11N3O3, and it consists of creatine plus one water molecule in the crystal lattice. The anhydrous base, creatine, has the formula C4H9N3O2. The compound appears as a white, odorless, crystalline powder and is classified as a guanidine derivative. It is distinct from creatinine, a breakdown product measured in clinical chemistry.
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.
== Personal life == In the early 1990s, Staley enrolled in several rehab programs, but he failed to stay clean for long. At one point, the other members of Alice in Chains flew to Los Angeles for weekly therapy at Staley's rehab. During the Dirt tour, Alice in Chains' manager, Susan Silver, hired bodyguards to keep Staley away from people who might try to pass him drugs, but he ended up relapsing on alcohol and drugs during the tour. Screaming Trees' Mark Lanegan recalled partying with Staley on tour and said that, "off stage, it was an insane, dark, drug and alcohol-fuelled frat party from start to finish, with Layne [Staley] and I raising hell, behaving like teenagers, staying up for days on end. We partook of whatever drugs came our way. Heroin, cocaine, painkillers, anything." Kurt Cobain's death in April 1994 scared Staley into temporary sobriety, but soon he was back into his addiction. Alice in Chains' managers turned down lucrative touring possibilities and kept the band off the road, hoping that would help Staley. Pearl Jam lead guitarist Mike McCready also tried to help Staley by inviting him to his side project, Mad Season. McCready had hoped that playing with sober musicians would encourage Staley. On October 29, 1996, Staley's former fiancée, Demri Lara Parrott, died of a drug overdose. Staley was placed on a 24-hour suicide watch, according to NME, which quoted a friend saying Staley was taking Parrott's death "extremely badly" and had fallen into a deep depression. Lanegan told Rolling Stone in 2002, "He never recovered from Demri's death.
== Richest royals == The Crown Property Bureau presides over the wealth of Thailand's king and royal family, judged to be the world's richest. Its holdings include over 7,588 rai (1,214.1 ha; 3,000 acres) of land in central Bangkok and shares in Siam Cement and Siam Commercial Bank. The king also owns the 545-carat Golden Jubilee Diamond, the largest cut and faceted diamond in the world.
The overactivation can lead to inflammation of vital organs, anemia via overactivated macrophages phagocytosing blood cells, and can potentially be fatal. In Trapani's paper he talks about how granzymes may have other functions, in addition to their ability to fight off infection. Granzyme A contains certain chemicals that allow it to cause proliferation in B cells to reduce the chance of cancer growth and formation. Test on mice have shown that granzyme A and B might not have a direct link to controlling viral infections, but helping accelerate the immune systems response.
Sources: en.wikipedia.org
Despite guidelines recommending that intensive blood sugar control be based on balancing immediate harms with long-term benefits, many people – for example people with a life expectancy of less than nine years who will not benefit, are over-treated. It is recommended that all people with type 2 diabetes get regular eye examinations. There is moderate evidence suggesting that treating gum disease by scaling and root planing results in an improvement in blood sugar levels for people with diabetes.
=== Contestants === 1st - Jasmin Bell, Pastry Instructor from Seattle, Washington 2nd - Jonathan Elias, Pastry Chef from Troy, Michigan 3rd - Jessica Scott, Executive Pastry Chef from San Diego, California 4th - Ray Vizcaino, Cake Decorator from San Diego, California 5th - Tyler Davis, Pastry Chef from St. Louis, Missouri 6th - Dina Melendez, Pastry Chef from Brooklyn, New York 7th - Cliff Butler, Pastry Chef from Austin, Texas 8th - Andrea Kratville, Home Baker from Sonora, California
== History == Diabulimia is not currently recognised in the DSM-5. Current diagnoses are based on the idea of insulin restriction being a feature of existing anorexia nervosa and bulimia nervosa. Diabulimia is gaining notability within scientific research. In 2019, NHS England began trialling specialist diabulimia clinics. Whilst access to eating disorder clinics is improving, access to specialist diabulimia services is not widely available.
== Mutations == Mutations or deletions in the AZF genes are associated with inability or lessened ability to create sperm. It may cause azoospermia (not having any measurable level of sperm in semen). Deletions in the USP9Y gene, which is located within AZF1, are usually associated with inability to form sperm.
Sources: en.wikipedia.org
=== Regulation === Translation is one of the key energy consumers in cells, hence it is strictly regulated. Numerous mechanisms have evolved that control and regulate translation in eukaryotes as well as prokaryotes. Regulation of translation can impact the global rate of protein synthesis which is closely coupled to the metabolic and proliferative state of a cell. To study this process, scientists have used a wide variety of methods such as structural biology, analytical chemistry (mass-spectrometry based), imaging of reporter mRNA translation (in which the translation of a mRNA is linked to an output, such as luminescence or fluorescence), detecting it via radioactive amino acid incorporation, and next-generation sequencing based methods. Other methods such as toeprinting assay can also be used to determine the location of ribosomes of a particular mRNA in vitro, and footprints of other proteins regulating translation. To delve deeper into this intricate process, scientists typically use a technique known as ribosome profiling. This method enables researchers to take a snapshot of the translatome, showing which parts of the mRNA are being translated into proteins by ribosomes at a given time. Ribosome profiling provides valuable insights into translation dynamics, revealing the complex interplay between gene sequence, mRNA structure, and translation regulation. Expanding on this concept, single-cell ribosome profiling, is a technique that allows the study of the translation process at the resolution of individual cells.
== Veterinary use == Oxymorphone provides up to 5–6 hours of clinical analgesia in dogs and cats following intravenous administration. Intramuscular administration in dogs produces approximately 90 minutes of antinociception. Oxymorphone is ineffective when administered via the oral-transmucosal route in cats, likely due to low bioavailability. Only few reports exist on its use in large animal species due to the cost of oxymorphone.
Because of the practical and, in particular, the financial scale of the program needed, the NCI decided to seek association with a pharmaceutical company, and in August 1989, it published a Cooperative Research and Development Agreement (CRADA) offering its current stock and supply from current bark stocks, and proprietary access to the data so far collected, to a company willing to commit to providing the funds to collect further raw material, isolate taxol, and fund a large proportion of clinical trials. In the words of Goodman and Welsh, authors of a substantial scholarly book on taxol, "The NCI was thinking, not of collaboration, ... but of a hand-over of taxol (and its problems)". Although the offer was widely advertised, only four companies responded to the CRADA, including the American firm Bristol-Myers Squibb (BMS), which was selected as the partner in December 1989. The choice of BMS later became controversial and was the subject of Congressional hearings in 1991 and 1992. While it seems clear the NCI had little choice but to seek a commercial partner, there was also controversy about the terms of the deal, eventually leading to a report by the General Accounting Office in 2003, which concluded the NIH had failed to ensure value for money. In related CRADAs with the USDA and Department of the Interior, Bristol-Myers Squibb was given exclusive first refusal on all Federal supplies of Taxus brevifolia. This exclusive contract lead to some criticism for giving BMS a "cancer monopoly".
Sources: en.wikipedia.org
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.
Creatine monohydrate contains creatine, but the two terms are not strictly interchangeable. The monohydrate includes water in the crystal, while creatine refers to the base molecule. Other creatine forms pair the molecule with different acids or carriers.
Dietary creatine is found mainly in meat and fish. The human body also synthesizes creatine from amino acids in the liver, kidneys, and pancreas. The monohydrate powder used in products is manufactured rather than extracted directly from food.
Purity testing often uses high-performance liquid chromatography to measure creatine and creatinine. Water content can be checked by Karl Fischer titration. Additional tests may cover heavy metals, residual solvents, and microbial contamination.