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.
Last reviewed on 2025-09-08. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Creatine monohydrate is stable under dry, cool conditions but can degrade when exposed to moisture and heat. In solution, it undergoes hydrolysis to creatinine, a cyclic derivative with little role in phosphagen energy transfer. The rate of conversion increases with temperature, storage time, and acidic or alkaline pH. Solid material kept in a sealed container at room temperature generally retains its composition for extended periods. Moisture uptake is a primary concern because it can accelerate breakdown and caking.
Analytical laboratories commonly use high-performance liquid chromatography to separate creatine from creatinine and related impurities. Ion chromatography, nuclear magnetic resonance, and titration assays can also quantify the compound. Water content is measured by Karl Fischer titration or loss on drying, because the monohydrate has a defined theoretical water fraction. Particle size, bulk density, and flowability are physical properties that affect blending and capsule filling. These measurements support quality control and help verify that a lot matches its specification.
| 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 |
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.
Creatine monohydrate is a crystalline organic compound formed from creatine and water in a one-to-one ratio. It belongs to the guanidino family and contains a methylated guanidine group attached to an acetate-like chain. The solid is commonly described as a white, odorless powder with a mildly bitter taste. Its molecular formula is C4H11N3O3·H2O, and the hydrated form is the most widely traded grade. The compound occurs naturally in vertebrate muscle and brain tissue, where it participates in rapid energy buffering.
In aqueous solution, creatine monohydrate exists mainly as a zwitterion, carrying both a positive guanidinium charge and a negative carboxylate charge. This charge separation raises water solubility relative to many neutral organic solids and helps explain its behavior in analytical separations. The monohydrate can lose its water of crystallization under sustained heat or low humidity, converting toward anhydrous creatine. Such transitions matter for mass balance calculations because the hydrate contributes water mass that is not part of the active creatine molecule.
The term creatine monohydrate is often shortened to creatine in casual usage, though other creatine forms exist, including citrate, nitrate, and hydrochloride salts. These alternative forms differ in solubility, pH behavior, and the amount of creatine delivered per unit mass. Regulatory categories vary by country: some jurisdictions treat it as a food ingredient, while others place it under supplement or drug frameworks depending on claims and presentation. Standard reference texts list it as a naturally occurring nitrogenous organic acid rather than a vitamin or mineral.
In addition, NADPH is used by enzymes including pyrroline-5-carboxylate synthase (P5CS) in proline biosynthesis, alpha-aminoadipic semialdehyde synthase (AASS) in lysine degradation, and 2,4-dienoyl-CoA reductase 1 (DECR) in the auxiliary pathway of mitochondrial beta oxidation of polyunsaturated fatty acids.
==== Shoulder replacement ==== For people who have shoulder osteoarthritis and do not respond to medications, surgical options include a shoulder hemiarthroplasty (replacing a part of the joint) and a total shoulder arthroplasty (replacing the joint). Demand for this treatment is expected to increase by 750% by the year 2030. There are different options for shoulder replacement surgeries, however there is a lack of evidence in the form of high-quality randomized controlled trials to determine which type of shoulder replacement surgery is most effective in different situations, what are the risks involved with different approaches, or how the procedure compares to other treatment options. There is some low-quality evidence that indicates that when comparing total shoulder arthroplasty over hemiarthroplasty, no large clinical benefit was detected in the short term. It is not clear if the risk of harm differs between total shoulder arthroplasty and a hemiarthroplasty approach.
In healthy mammalian tissues, estimates of the ratio of free NAD+ to NADH in the cytoplasm typically lie around 700:1; the ratio is thus favorable for oxidative reactions. The ratio of total NAD+/NADH is much lower, with estimates ranging from 3–10 in mammals. In contrast, the NADP+/NADPH ratio is normally about 0.005, so NADPH is the dominant form of this coenzyme. These different ratios are key to the different metabolic roles of NADH and NADPH.
Sources: en.wikipedia.org
== Names == The war is also known under other names, such as the Second Gulf War (not to be confused with the 2003 Iraq War, also referred to as such), Persian Gulf War, Kuwait War, or Iraq War before the term "Iraq War" became identified with the 2003 Iraq War, also known in the US as "Operation Iraqi Freedom". The war was named Umm al-Ma'arik ("mother of all battles") by Iraqi officials. After the US invasion of Iraq in 2003, the Gulf War of 1990–1991 is often known as the "First Iraq War". The following names have been used to describe the conflict itself: Gulf War and Persian Gulf War are the most common terms for the conflict used within western countries. It may also be called the First Gulf War, to distinguish it from the 2003 invasion of Iraq and the subsequent Iraq War. Some authors have called it the Second Gulf War to distinguish it from the Iran–Iraq War. Liberation of Kuwait (Arabic: تحرير الكويت) (taḥrīr al-kuwayt) is the term used by Kuwait and most of the coalition's Arab states, including Saudi Arabia, Bahrain, Egypt, and the United Arab Emirates. Terms in other languages include French: la Guerre du Golfe and Guerre du Koweït (War of Kuwait); German: Golfkrieg (Gulf War) and Zweiter Golfkrieg (Second Gulf War).
A surface is prepared with a known quantity of capture antibody. Any nonspecific binding sites on the surface are blocked. The antigen-containing sample is applied to the plate, and captured by antibody. The plate is washed to remove unbound antigen. A specific antibody is added, and binds to antigen (hence the 'sandwich': the antigen is stuck between two antibodies). This primary antibody could be in the serum of a donor, to be tested for reactivity towards the antigen. Enzyme-linked secondary antibodies are applied as detection antibodies, which bind specifically to the antibody's Fc region (nonspecific). The plate is washed to remove the unbound antibody-enzyme conjugates. A chemical is added to be converted by the enzyme into a color, fluorescent, or electrochemical signal. The absorbance, fluorescence, or electrochemical signal (e.g., current) of the plate's wells is measured to determine the presence and quantity of the antigen. The image to the right includes the use of a secondary antibody conjugated to an enzyme, although, in the technical sense, this is not necessary if the primary antibody is conjugated to an enzyme (which would be direct ELISA). However, the use of a secondary-antibody conjugate avoids the expensive process of creating enzyme-linked antibodies for every antigen one might want to detect. By using an enzyme-linked antibody that binds the Fc region of other antibodies, this same enzyme-linked antibody can be used in a variety of situations.
=== Legacy === De Duve founded a multidisciplinary biomedical research institute at Université catholique de Louvain in 1974, originally named the International Institute of Cellular and Molecular Pathology (ICP). He remained its president until 1991. On his 80th birthday in 1997 it was renamed the Christian de Duve Institute of Cellular Pathology. In 2005 its name was further contracted to simply the de Duve Institute. De Duve was one of the founding members of the Belgian Society of Biochemistry and Molecular Biology, established on 15 September 1951. De Duve is remembered as an inventor of important scientific terminology. He coined the word lysosome in 1955, peroxisome in 1966, and autophagy, endocytosis, and exocytosis in one instance at the Ciba Foundation Symposium on Lysosomes held in London during 12–14 February 1963, while he, "was in a word-coining mood." De Duve's life, including his work resulting in a Nobel Prize, and his passion for biology is the subject of a documentary film Portrait of a Nobel Prize: Christian de Duve (Portrait de Nobel : Christian de Duve), directed by Aurélie Wijnants. It was first aired on Eurochannel in 2012.
== Service branches == The PLA consists of four services (Ground Force, Navy, Air Force, and Rocket Force) and four arms (Aerospace Force, Cyberspace Force, Information Support Force, and Joint Logistics Support Force).
Sources: en.wikipedia.org
== Long-lasting erections == Antiandrogens can considerably relieve and prevent priapism (potentially painful penile erections that last more than four hours) via direct blockade of penile ARs. In accordance, bicalutamide, at low dosages (50 mg every other day or as little as once or twice weekly), has been found in a series of case reports to completely resolve recurrent priapism in men without producing significant side effects, and is used for this indication off-label. In the reported cases, libido, rigid erections, the potential for sexual intercourse, orgasm, and subjective ejaculatory volume have all remained intact or unchanged, and gynecomastia has not developed when bicalutamide is administered at a total dosage of 25 mg/day or less. Some gynecomastia and breast tenderness developed in one patient treated with 50 mg/day, but significantly improved upon the dosage being halved. The observed tolerability profile of bicalutamide in these subjects has been regarded as significantly more favorable than that of GnRH analogues and estrogens (which are also used in the treatment of this condition). However, although successful and well tolerated, very few cases have been reported. Despite the apparent efficacy of bicalutamide for priapism, a small clinical study found that bicalutamide monotherapy at a dosage of 50 mg/day had no effect on nocturnal erections in men with prostate cancer.
Chick-fil-A has donated over $5 million, via the WinShape Foundation, to groups that oppose same-sex marriage. In response, students at several colleges and universities worked to ban or remove the company's restaurants from their campuses. In June and July 2012, Chick-fil-A's chief operating officer Dan T. Cathy made several public statements about same-sex marriage, saying that those who "have the audacity to define what marriage is about" were "inviting God's judgment on our nation". Several prominent politicians expressed disapproval. Boston Mayor Thomas Menino and Chicago Alderman Proco "Joe" Moreno said they hoped to block franchise expansion into their areas. The proposed local bans drew criticism from liberal pundits, legal experts, and the American Civil Liberties Union. The Jim Henson Company, which had a Pajanimals kids' meal toy licensing arrangement with Chick-fil-A, said it would cease its business relationship, and donate the payment to the Gay & Lesbian Alliance Against Defamation. Chick-fil-A stopped distributing the toys, claiming that unrelated safety concerns had arisen before the controversy. Chick-fil-A released a statement on July 31, 2012, saying, "We are a restaurant company focused on food, service, and hospitality; our intent is to leave the policy debate over same-sex marriage to the government and political arena." In response to the controversy, former Arkansas Governor Mike Huckabee initiated a Chick-fil-A Appreciation Day movement to counter a boycott of Chick-fil-A launched by same-sex marriage activists.
== Research == In 1960 he commenced work in Cambridge on his PhD degree under the supervision of Fred Hoyle, and published his first scientific paper "On Graphite Particles as Interstellar Grains" in Monthly Notices of the Royal Astronomical Society in 1962. He was awarded a PhD degree in mathematics in 1963 and was elected a Fellow of Jesus College Cambridge in the same year. In the following year he was appointed a Staff Member of the Institute of Astronomy, Cambridge. Here he continued to work on the nature of interstellar dust, publishing many papers in this field, that led to a consideration of carbon-containing grains as well as the older silicate models. Wickramasinghe published the first definitive book on Interstellar Grains in 1967. He has made many contributions to this field, publishing over 350 papers in peer-reviewed journals, over 75 of which are in Nature. Hoyle and Wickramasinghe further proposed a radical kind of panspermia that included the claim that extraterrestrial life forms enter the Earth's atmosphere and were possibly responsible for epidemic outbreaks, new diseases, and genetic novelty that Hoyle and Wickramasinghe contended was necessary for macroevolution. Chandra Wickramasinghe had the longest-running collaboration with Fred Hoyle. Their publications on books and papers arguing for panspermia and a cosmic hypothesis of life are controversial and, in particular detail, essentially contra the scientific consensus in both astrophysics and biology.
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.
A sealed container at room temperature, away from moisture and direct heat, is suitable for most solid material. Keeping the lid closed limits water uptake and caking. Long-term storage in a refrigerator is not necessary if the powder remains dry.