Creatinine comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-08-25. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
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.
| 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 |
Identity and purity are assessed with several complementary methods. High-performance liquid chromatography can separate creatine from creatinine and related impurities, often with ultraviolet detection. Nuclear magnetic resonance and infrared spectroscopy provide structural confirmation, while Karl Fischer titration measures water content. Elemental analysis and mass spectrometry may be used for additional confirmation, especially in research or forensic settings. No single method captures every quality attribute, so laboratories typically combine results and compare them against a specification.
Creatine monohydrate is sold as a dietary ingredient in some countries and as a food supplement in others. Regulatory frameworks vary, so purity limits, labeling rules, and permitted claims are not globally uniform. In the United States, it falls under dietary supplement rules, whereas the European Union treats it as a food supplement ingredient. Pharmacopeial monographs, where they exist, can provide public quality standards, but not every product is required to meet them. Questions about long-term effects and patterns of use remain areas of active study rather than settled regulatory findings.
Solid creatine monohydrate is generally stable when kept cool and dry, but it can hydrolyze to creatinine over time. Moisture, heat, and acidic conditions accelerate this conversion, which reduces assay values and changes the material's properties. Creatinine is a cyclic dehydration product that is also a normal human metabolite, so its presence in a sample is not necessarily a health concern by itself. In quality testing, creatinine is monitored as a marker of degradation and purity.
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.
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.
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.
The vast majority of reported cases of foodborne illness occur as individual or sporadic cases. The origin of most sporadic cases is undetermined. In the United States, where people eat outside the home frequently, 58% of cases originate from commercial food facilities (2004 FoodNet data). An outbreak is defined as occurring when two or more people experience similar illness after consuming food from a common source. Often, a combination of events contributes to an outbreak, for example, food might be left at room temperature for many hours, allowing bacteria to multiply which is compounded by inadequate cooking which results in a failure to kill the dangerously elevated bacterial levels. Outbreaks are usually identified when those affected know each other. Outbreaks can also be identified by public health staff when there are unexpected increases in laboratory results for certain strains of bacteria. Outbreak detection and investigation in the United States is primarily handled by local health jurisdictions and is inconsistent from district to district. It is estimated that 1–2% of outbreaks are detected. When an outbreak is suspected, investigators conduct an epidemiologic assessment, laboratory analysis, and environmental assessment simultaneously. Investigators construct an epidemic curve, a histogram of cases over time, to characterize transmission patterns and narrow the exposure window. Case-control studies are commonly used, comparing foods eaten by ill individuals against those eaten by healthy controls to identify statistically significant exposures.
Freeman made six appearances in various films in 2005. In the drama An Unfinished Life, Freeman plays Mitch, a neighbor of a Wyoming rancher (Robert Redford). The film had a mixed response; The Guardian critic thought it was amiable but questioned the purpose of Freeman's "sidekick" role. Freeman's authoritative voice led to his narration of two documentaries; Steven Spielberg's War of the Worlds and the Academy Award-winning March of the Penguins. He also appeared in Christopher Nolan's Batman Begins, the first installment in what would become The Dark Knight Trilogy, as the fictional Lucius Fox. After this, he co-starred with Jet Li in the action-thriller Unleashed, playing Sam, a blind piano tuner who helps Li's character turn his life around. The film gained a mixed-to-positive reception; Peter Hartlaub of San Francisco Chronicle was confused with the genre and thought Freeman's character interrupted the narrative. Freeman's next role was in the thriller Edison, which bombed at the box office. In his last release of 2005, he provided the voice of Neil Armstrong in the documentary Magnificent Desolation: Walking on the Moon 3D. Freeman starred in 2006's The Contract, as assassin Frank Carden opposite John Cusack. The film was released direct-to-video, which critic John Cornelius suggests was unsurprising, considering the generic formula of the thriller. Freeman next appeared in Lucky Number Slevin (2006), a crime thriller directed by Paul McGuigan.
Most individuals become relatively tame within a short time, and are capable of recognising individual humans and discriminating between familiar and unfamiliar keepers. Komodo dragons have also been observed to engage in play with a variety of objects, including shovels, cans, plastic rings, and shoes. This behavior does not seem to be "food-motivated predatory behavior".
Sources: en.wikipedia.org
1977: Argentine-Canadian scientist Veronica Dahl became the first graduate at Université d'Aix-Marseille II (and one of the first women in the world) to earn a PhD in artificial intelligence. 1977: Canadian-American Elizabeth Stern published her research on the link between birth control pills – which contained high levels of estrogen at the time – and the increased risk of cervical cancer development in women. Her data helped pressure the pharmaceutical industry into providing safer contraceptive pills with lower hormone doses. 1977: Janina Oszast is among the first Polish palaeobotanists attempting biogeographic synthesis of Miocene land sediments. She was also the first person in Poland to identify pollen from a range of herbaceous plants and the first to find pollen grains of Ephedra in glaciation period deposits. 1978: Anna Jane Harrison became the first female president of the American Chemical Society. 1978: American biochemist Mildred Cohn served as the first female president of the American Society for Biochemistry and Molecular Biology, then called the American Society of Biological Chemists.
16 February – Former footballer Ciaran Dickson is sentenced to six years in prison by the High Court in Glasgow for the hit-and-run killing of Aidan Pilkington in September 2021, when he was more than three times over the drink drive limit. Scotland is to scrap its Super 6 rugby series and reinstate a national "A team" as part of a comprehensive restructuring programme. 17 February – Delegates at the Scottish Labour Party conference pass a resolution calling for an immediate ceasefire in Gaza. Two men are killed in a road traffic accident involving three cars on the B9077 in Maryculter, Aberdeenshire. 20 February – Heather Woodbridge, aged 29, is appointed as leader of Orkney Islands Council, becoming Scotland's youngest council leader and the first woman to lead Orkney Islands Council. The BBC announces plans to reshape the BBC Scotland TV channel, including axing the hour-long news programme The Nine and replacing it with a 30-minute programme. 22 February – Argyll and Bute Council votes to raise its council tax by 10%, and rejects the Scottish Government's council tax freeze by doing so. 23 February – The Scottish Government publishes draft legislation proposing a ban on the sale of disposable vapes in Scotland by 1 April 2025. 24 February – Police Scotland begins an investigation after burnt human remains are found near Motherwell Football Club. 25 February – The Scottish Government confirms that Economy Secretary Màiri McAllan, who is pregnant, will take maternity leave during the summer, becoming the second Scottish Government minister to do so.
This allows for convenient once-daily administration. The medication is eliminated predominantly by metabolism in the liver (83 to 85%) but also by residual excretion by the kidneys, unchanged (11%). Anastrozole is excreted primarily in urine but also to a lesser extent in feces.
Benefits to this method include that the person who is suspected of drug use does not need to be confronted or aware of testing. Only a very small amount of material is needed to obtain results, and can be used to test powder, pills, capsules, crystals, or organic material. There is also the ability to detect illicit material when mixed with other non-illicit materials. The tests are used for general screening purposes, offering a generic result for the presence of a wide range of drugs, including heroin, cocaine, methamphetamine, amphetamine, ecstasy/MDMA, methadone, ketamine, PCP, PMA, DMT, MDPV, and may detect rapidly evolving synthetic designer drugs. Separate tests for cannabis are also available. There are five primary color-test reagents used for general screening purposes. The Marquis reagent turns into a variety of colors when in the presence of different substances. Dille-Koppanyi reagent uses two chemical solutions which turns a violet-blue color in the presence of barbiturates. Duquenois-Levine reagent is a series of chemical solutions that turn to the color of purple when the vegetation of marijuana is added. Van Urk reagent turns blue-purple when in the presence of LSD. Scott test's chemical solution shows up as a faint blue for cocaine base. In recent years, the use of presumptive test kits in the criminal justice system has come under great scrutiny due to the lack to forensic studies, questioned reliability, rendering of false positives with legal substances, and wrongful arrests.
Sources: en.wikipedia.org
The human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary glands, pancreas, liver, and gallbladder). Digestion involves the breakdown of food into smaller and smaller components, until they can be absorbed and assimilated into the body. The process of digestion has three stages: the cephalic phase, the gastric phase, and the intestinal phase. The first stage, the cephalic phase of digestion, begins with secretions from gastric glands in response to the sight and smell of food, and continues in the mouth with the mechanical breakdown of food by chewing, and the chemical breakdown by digestive enzymes in the saliva. Saliva contains amylase, and lingual lipase, secreted by the salivary glands, and serous glands on the tongue. Chewing mixes the food with saliva to produce a food bolus to be swallowed down the esophagus to enter the stomach. The second stage, the gastric phase, takes place in the stomach, where the food is further broken down by mixing with gastric juice until it passes into the duodenum, the first part of the small intestine. The intestinal phase where the partially digested food is mixed with pancreatic digestive enzymes completes the process of digestion. Digestion is helped by the chewing of food carried out by the muscles of mastication, the tongue, and the teeth, and also by the contractions of peristalsis, and segmentation. Gastric juice containing gastric acid, and the production of mucus in the stomach, are essential for the continuation of digestion.
The larger group of Japanese aircraft had flown to Guam and were intercepted over Orote Field by 27 Hellcats while landing. Thirty of the forty-nine Japanese aircraft were shot down, and the rest were damaged beyond repair. Aboard the Lexington afterward, a pilot was heard to remark "Hell, this is like an old-time turkey shoot!"
In a case where gaseous exchange is impaired, mechanical ventilation and intubation may be necessary and if bronchiolitis obliterans develop within 2 to 6 weeks of nitrogen dioxide exposure, corticosteroid therapy or anticholinergic medications may be required for 6 to 12 months to lower the body overreaction to nitrogen dioxide gas.
The 2026 FIFA World Cup was the 23rd FIFA World Cup, the quadrennial international men's soccer championship contested by the national teams of the member associations of FIFA. The tournament began on June 11, 2026, and concluded on July 19 with Spain winning the championship for the second time. It was jointly hosted by 16 cities—11 in the United States, 3 in Mexico, and 2 in Canada. The tournament was the first FIFA World Cup to be hosted by three countries and the first to include 48 teams, an expansion from the previous 32-team format. The 2026 tournament was the second World Cup to be hosted by multiple nations, after the 2002 edition. Mexico became the first country to host the World Cup three times, having hosted the 1970 and 1986 tournaments. The United States previously hosted the World Cup in 1994, while it was Canada's first time hosting the tournament. The event returned to its traditional June–July schedule after the 2022 World Cup in Qatar, which was uniquely held in November and December to avoid Qatar's extreme summer heat. Canada, Mexico, and the United States qualified automatically as hosts, while Cape Verde, Curaçao, Jordan, and Uzbekistan made their World Cup debuts. For the first time in the tournament's history, the top four teams from the FIFA Men's World Ranking at the time of the contest (Argentina, Spain, France, and England) advanced to the semifinals. Spain won the final against defending champion Argentina 1–0 after extra time, winning its second title and first since 2010.
Richard G. Hiskey (May 21, 1929 – July 28, 2016) was an American chemist and Alumni Distinguished Professor of Chemistry at University of North Carolina at Chapel Hill. Hiskey joined the department of chemistry of the University of North Carolina at Chapel Hill in 1958. He served in various capacities within the university, including director of graduate studies (1965-1970) and chairman of the department (1970-1975), (elected) chairman of the division of natural sciences from 1975 to 1981, and faculty representative to the Atlantic Coast Conference and National Association of Intercollegiate Athletics (1985-1995).
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.
Dry, sealed creatine monohydrate can remain stable for years, but storage conditions affect its shelf life. Moisture, heat, and repeated opening of containers can reduce quality over time.