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Creatine monohydrate is a crystalline compound formed from creatine and one molecule of water. Its systematic name is N-(aminoiminomethyl)-N-methylglycine monohydrate, and it appears as a white, odorless powder with limited solubility in water. The monohydrate is the most common solid form used in research and commercial products because it is stable under dry conditions. The anhydrous form lacks the water of crystallization and differs slightly in molar mass. Both forms participate in the same biochemical reactions once dissolved.
In the body, creatine is synthesized from the amino acids arginine, glycine, and methionine, primarily in the liver and kidneys. It is transported to muscle and other tissues, where it is phosphorylated to phosphocreatine by creatine kinase. This phosphagen system provides a rapid source of adenosine triphosphate during short, intense contractions. Dietary creatine comes mainly from meat and fish, and the body's total pool is influenced by both synthesis and intake.
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 form; anhydrous is C4H9N3O2 |
| Molar mass | 149.15 g/mol | For the monohydrate |
| Appearance | White crystalline powder | Odorless, slightly bitter taste |
| Solubility in water | ~13 g/L at 25 °C | Poorly soluble; increases with temperature |
| CAS Registry Number | 6020-87-7 | For creatine monohydrate |
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.
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.
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.
Quality control for creatine monohydrate begins with identity confirmation and assay determination. Laboratories commonly use high-performance liquid chromatography with ultraviolet detection, often after derivatization or using a suitable column, to quantify creatine. Karl Fischer titration measures water content, which helps verify the monohydrate stoichiometry. Additional tests screen for heavy metals, residual solvents, and microbial contamination depending on the intended use. These tests establish composition and purity rather than biological effect.
Stability studies examine how creatine monohydrate changes under controlled temperature and humidity. The solid is generally stable when kept dry, but moisture can promote hydrolysis to creatinine, especially in solution or at elevated temperatures. Color, odor, and assay values are monitored over time to detect degradation. Because degradation pathways depend on storage conditions, shelf-life claims should specify the tested packaging, temperature, and humidity. Open questions remain about the long-term behavior of different crystal habits and particle sizes.
Regulatory treatment of creatine monohydrate varies by country and intended use. In some jurisdictions it is sold as a dietary supplement, while in others it may be treated as a food ingredient or a pharmaceutical raw material. Pharmacopeial monographs, where available, define identification, assay limits, and impurity thresholds. Manufacturers often follow these monographs or internal specifications to ensure batch-to-batch consistency. Analytical method validation is important because different methods can yield different apparent purity values if sample preparation or detection conditions are not controlled.
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.
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.
== S == sarcoplasmic reticulum - satellite DNA - scientific notation - SDS-PAGE - second messenger - second messenger system - secondary structure - secretin - selectin - sensory receptor - sequence (biology) - sequence homology - sequence motif - sequencing - serine - serotonin - serotonin receptor - serpin - sexual reproduction - SH3 domain - SI - sigma factor - signal peptide - signal recognition particle - signal sequence - signal transduction - sincalide - skeleton - skin - smooth ER - sodium channel - sodium-hydrogen antiporter - soluble - solution - solvation - solvent - somatomedin - somatomedin receptor - somatostatin - somatostatin receptor - somatotropin - somatotropin receptor - somatotropin-releasing hormone - somatropin - sp1 transcription factor - spectrin - spectroscopy - src gene - src-family kinase - SSRI - starch - stem cell - stereochemistry - steroid 17alpha-monooxygenase - steroid 21-monooxygenase - steroid receptor - stimulatory gs G-protein - stoichiometry - structural biology - structural domain - Structural formula - structural motif - substance P - substrate - sugar - sulfur - supercoil - superfamily - superoxide - surface immunoglobulin - surface plasmon resonance - suspension (chemistry) - synapse - synthetic vaccine - systems biology
United States Court of Appeals, Eighth Circuit. Decided Oct. 31, 1979. LAY, Circuit Judge. John Arthur Stieren appeals from the judgment of conviction for possession of cocaine with intent to distribute and dispense under 21 U.S.C. § 841(a)(1). Stieren contends that the statute is unconstitutional because "cocaine is classified as a narcotic under Schedule II of 21 U.S.C. § 812(c) when as a matter of scientific and medical fact cocaine is not a narcotic but is a non-narcotic stimulant." The sufficiency of the evidence is not disputed. Stieren was convicted after special agents testified that he had and attempted to sell them a large quantity of cocaine. Defendant urges that the testimony and reports by physicians and scientists demonstrate that cocaine is not a narcotic. He also cites cases that hold that cocaine is not a narcotic under the pharmacological definition of the term. State v. Erickson, 574 P.2d 1 (Alaska 1978). It is within the legislative prerogative to classify cocaine, which is a non-narcotic central nervous system stimulant, as a narcotic for penalty and regulatory purposes. 21 U.S.C. § 802(16)(A). The use of cocaine poses serious problems for the community and has a high potential for abuse. Congress's choice of penalty reflects a societal policy that must be adhered to by the courts.2 Congress has the power to reclassify cocaine. This power has been delegated to the Attorney General. 21 U.S.C. § 811(a)(1). If cocaine is to be reclassified, the defendant's arguments should be made to the legislative branch, not the courts.
Larger living areas on the Skylab space station (1973–1974) allowed for an on-board refrigerator and freezer. This allowed perishable and frozen items to be stored, making microgravity the primary obstacle of future missions. When Skylab's solar panels were damaged during its launch and the station had to rely on minimal power from the Apollo Telescope Mount until Skylab 2 crewmembers performed repairs, the refrigerator and freezer were among the systems that Mission Control kept operational. The Orbital Work Shop (OWS) module had a specially designed wardroom dedicated for food preparation and dining (see image on the right). A dining table was also available, and was designed to avoid hierarchical positions through its triangular layout and to support social cohesion. The table and chairs were fastened to the floor and fitted with foot and thigh restraints, allowing for a more normal eating experience. The trays used could warm the food, and had magnets to hold eating utensils and scissors used for opening food containers. It could accommodate all three crew members at the same time using a variety of microgravity restraints. As a result of the improved eating arrangement, astronauts aboard Skylab maintained some of the best nutritional intake recorded.
Sources: en.wikipedia.org
dbAMP is an online resource that addresses various topics such as annotations of antimicrobial peptides (AMPs) including sequence information, antimicrobial activities, post-translational modifications (PTMs), structural visualization, antimicrobial potency, target species with minimum inhibitory concentration (MIC), physicochemical properties, or AMP–protein interactions. Tools such as PeptideRanker, PeptideLocator, and AntiMPmod allow for the prediction of antimicrobial peptides while others have been developed to predict antifungal and anti-Tuberculosis activities.
=== Beta-adrenoceptor antagonists === Propranolol is originally used for high blood pressure and heart diseases. It can also be used to treat anxiety with symptoms like tremor or increased heart rate. They work on the nervous system and alleviate the symptoms as a relief. Propranolol is also commonly used for public speaking when one is nervous.
=== Ireland === On 7 April, a series of protests against rising fuel prices began across major road networks, cities and ports in The Republic of Ireland. The protests continued until 14 April also causing a vote of no confidence in its government.
Sources: en.wikipedia.org
It is a compound made of creatine bound to one water molecule. It appears as a white crystalline powder and is the most common solid form of creatine used in research and supplements.
Creatine is converted to phosphocreatine in muscle, which helps regenerate adenosine triphosphate during brief, high-intensity activity. The body also obtains creatine from foods such as meat and fish.
The creatine molecule is the same whether from food or supplements, but the monohydrate form includes a water molecule in its crystal structure. Once dissolved, the monohydrate and food-derived creatine are chemically identical in the body.
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.