A practical reference on HPLC-UV: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-04-25 and is reviewed periodically as new material appears.
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 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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical name | N-(aminoiminomethyl)-N-methylglycine monohydrate | Nomenclature varies across sources. |
| Common synonyms | Creatine hydrate; creatine monohydrate | “Monohydrate” specifies one water per creatine. |
| Appearance | White to off-white crystalline powder | Particle size and flowability vary by grade. |
| Solubility class | Soluble in water; slightly soluble in ethanol | Dissolution increases with temperature and stirring. |
| Typical storage | Tightly closed container at 15–25 °C | Protect from moisture and excessive heat. |
Stability studies typically examine the effects of temperature, humidity, and light on creatine monohydrate. Sealed containers stored in cool, dry conditions help limit moisture uptake and hydrolysis. Elevated temperature and high relative humidity can accelerate conversion to creatinine, especially in aqueous solutions. In solid dosage forms, excipients and processing steps may also affect stability. Published stability data are not fully consistent across studies because test conditions and analytical methods vary.
Quality control of creatine monohydrate relies on a combination of identity, purity, and moisture tests. High-performance liquid chromatography with ultraviolet detection is widely used to separate creatine from creatinine and other related nitrogenous compounds. Spectroscopic methods such as infrared and nuclear magnetic resonance provide structural confirmation. Because the material is a hydrate, water content is measured separately, often by Karl Fischer titration. These tests together establish whether a lot meets a defined specification.
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.
Regulatory status varies by country. In the United States, creatine monohydrate is sold as a dietary supplement ingredient, while in the European Union it is placed on the market as a food supplement component. Some jurisdictions have established purity monographs or permitted health claims, while others treat it as a novel food or require notification. Product labels may state the amount of creatine monohydrate or the equivalent creatine content, and the two figures can differ. Independent testing programs sometimes check identity, potency, and contaminant limits.
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.
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 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.
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.
=== Weak base and weak coordinating anion === As perchloric acid is one of the strongest mineral acids, perchlorate is a very weak base in the sense of Brønsted–Lowry acid–base theory. As it is also generally a weakly coordinating anion, perchlorate is commonly used as a background, or supporting, electrolyte.
=== 1 September === The RSF claimed to have taken the Dimsilk and Ziyadia neighbourhoods of El Fasher along with the Mellit bus station in the same city. At the same time, four people were killed by RSF shelling on the Abu Shouk camp, while at least 18 people were killed by RSF shelling on El Fasher.
Some stellate cells were present in the macula flava, but started to show some signs of degeneration. The stellate cells synthesized fewer extracellular matrix molecules, and the cytoplasmic processes were shown to be short and shrinking, suggesting a decreased activity. Those results confirm the hypothesis that phonation stimulates stellate cells into producing more extracellular matrix. Furthermore, using a specially designed bioreactor, Titze et al. showed that fibroblasts exposed to mechanical stimulation have differing levels of extracellular matrix production from fibroblasts that are not exposed to mechanical stimulation. The gene expression levels of extracellular matrix constituents such as fibronectin, MMP1, decorin, fibromodulin, hyaluronic acid synthase 2, and CD44 were altered. All those genes are involved in extracellular matrix remodeling, thus suggesting that mechanical forces applied to the tissue, alter the expression levels of extracellular matrix related genes, which in turn allow the cells present in the tissue to regulate the extracellular matrix constituent synthesis, thus affecting the tissue's composition, structure, and biomechanical properties. In the end, cell-surface receptors close the loop by giving feedback on the surrounding extracellular matrix to the cells, affecting also their gene expression level.
== Indications for use == Abciximab is indicated for use in individuals undergoing percutaneous coronary intervention (angioplasty with or without stent placement). The use of abciximab in this setting is associated with a decreased incidence of ischemic complications due to the procedure and a decreased need for repeated coronary artery revascularization in the first month following the procedure. Research also shows that this drug can be of use for patients with diabetes and chronic kidney disease. It is not the appropriate drug of choice if a patient is scheduled for an emergency surgery (i.e., heart surgery) because bleeding time may take about 12 hours to normalize. Pediatric uses include treatment of Kawasaki disease.
The Alexander von Humboldt Fellowship to Germany (2003–2005) Visiting Scientist to the University of Pittsburgh, (2007–2008) The ANDI Bright Contest Award for the Best African Innovative Researcher, South Africa (2009) Young Scientist (representing Nigeria) at the "Summer Davos" Annual Meeting of New Champions, Tianjin, China (2010) CV Raman Senior Fellowship, India (2013) Fellow of the Nigerian Academy of Science (2017) Pioneer national president of the Nanomedicine Society of Nigeria Recipient of various national and international grants and a reviewer to several national and international journals.
Sources: en.wikipedia.org
=== Territorial disputes, internal conflicts, and armed conflicts === A 2017 study found that autocratic leaders whose states were involved in international rivalries over disputed territory were more likely to be overthrown in a coup. The authors of the study provide the following logic for why this is:Autocratic incumbents invested in spatial rivalries need to strengthen the military in order to compete with a foreign adversary. The imperative of developing a strong army puts dictators in a paradoxical situation: to compete with a rival state, they must empower the very agency—the military—that is most likely to threaten their own survival in office.However, two 2016 studies found that leaders who were involved in militarized confrontations and conflicts were less likely to face a coup. A 2019 study found that states that had recently signed civil war peace agreements were much more likely to experience coups, in particular when those agreements contained provisions that jeopardized the interests of the military.
=== Stannane === Organostannane reagents are common. Several are commercially available. Stannane reagents can be synthesized by the reaction of a Grignard or organolithium reagent with trialkyltin chlorides. For example, vinyltributyltin is prepared by the reaction of vinylmagnesium bromide with tributyltin chloride. Hydrostannylation of alkynes or alkenes provides many derivatives. Organotin reagents are air and moisture stable. Some reactions can even take place in water. They can be purified by chromatography. They are tolerant to most functional groups. Some organotin compounds are heavily toxic, especially trimethylstannyl derivatives. The use of vinylstannane, or alkenylstannane reagents is widespread. In regards to limitations, both very bulky stannane reagents and stannanes with substitution on the α-carbon tend to react sluggishly or require optimization. For example, in the case below, the α-substituted vinylstannane only reacts with a terminal iodide due to steric hindrance.
99Mo → 99mTc + e− + νe The molybdenum isotope has a half-life of approximately 66 hours (2.75 days), so the generator has a useful life of about two weeks. Most commercial 99mTc generators use column chromatography, in which 99Mo in the form of molybdate, MoO42− is adsorbed onto acid alumina (Al2O3). When the 99Mo decays it forms pertechnetate TcO4−, which because of its single charge is less tightly bound to the alumina. Pulling normal saline solution through the column of immobilized 99Mo elutes the soluble 99mTc, resulting in a saline solution containing the 99mTc as the dissolved sodium salt of the pertechnetate. The pertechnetate is treated with a reducing agent such as Sn2+ and a ligand. Different ligands form coordination complexes which give the technetium enhanced affinity for particular sites in the human body. 99mTc decays by gamma emission, with a half-life: 6.01 hours. The short half-life ensures that the body-concentration of the radioisotope falls effectively to zero in a few days.
== Function == Erythroferrone is a hormone that regulates iron metabolism through its actions on hepcidin. As shown in mice and humans, it is produced in erythroblasts, which proliferate when new red cells are synthesized, such as after hemorrhage when more iron is needed (so-called stress erythropoiesis). This process is governed by the renal hormone, erythropoietin. Its mechanism of action is to inhibit the expression of the liver hormone, hepcidin. This process is governed by the renal hormone, erythropoietin. By suppressing hepcidin, ERFE increases the function of the cellular iron export channel, ferroportin. This then results in increased iron absorption from the intestine and mobilization of iron from stores, which can then be used in the synthesis of hemoglobin in new red blood cells. Erythroferrone inhibits hepcidin synthesis by binding bone morphogenetic proteins and thereby inhibiting the bone morphogenetic protein pathway that controls hepcidin expression. Mice deficient in the gene encoding erythroferrone have transient maturational hemoglobin deficits and impaired hepcidin suppression in response to phlebotomy with a delayed recovery from anemia. In its role as myonectin, it also promotes lipid uptake into adipocytes and hepatocytes.
In the war against the Marcomanni in 167, the town was hard pressed; its fortifications had fallen into disrepair during the long peace. Nevertheless, when in 168 Marcus Aurelius made Aquileia the principal fortress of the empire against the barbarians of the North and East, it rose to the pinnacle of its greatness and soon had a population of 100,000. Septimius Severus visited in 193. In 238, when the town took the side of the Senate against the emperor Maximinus Thrax, the fortifications were hastily restored, and proved of sufficient strength to resist for several months, until Maximinus himself was assassinated.
Sources: en.wikipedia.org
=== 1989 local government reforms === For many decades until the local government reforms of 1989, a borough with more than 20,000 people could be proclaimed a city. The boundaries of councils tended to follow the edge of the built-up area, so little distinction was made between the urban area and the local government area. New Zealand's local government structural arrangements were significantly reformed by the Local Government Commission in 1989 when approximately 700 councils and special purpose bodies were amalgamated to create 87 new local authorities. Regional councils were reduced in number from 20 to 13, territorial authorities (city/district councils) from 200 to 75, and special purpose bodies from over 400 to 7. The new district and city councils were generally much larger and most covered substantial areas of both urban and rural land. Many places that once had a city council were now being administered by a district council. As a result, the term "city" began to take on two meanings. City also came to be used in a less formal sense to describe major urban areas independent of local body boundaries. This informal usage is jealously guarded. Gisborne, for example, adamantly described itself as the first city in the world to see the new millennium. Gisborne is administered by a district council, but its status as a city is not generally disputed. Under current law, an urban area has to be at least 50,000 residents before it can be officially proclaimed as a city.
== Agents == Currently, there are 10 ACE inhibitors approved for use in the United States by the FDA: captopril (1981), enalapril (1985), lisinopril (1987), benazepril (1991), fosinopril (1991), quinapril (1991), ramipril (1991), perindopril (1993), moexipril (1995) and trandolapril (1996). ACE inhibitors are easily identifiable by their common suffix, '-pril'. ACE inhibitors can be divided into three groups based on their molecular structure of the enzyme binding sites (sulfhydryl, phosphinyl, carboxyl) to the active center of ACE:
Spironolactone, sold under the brand name Aldactone among others, is classed as a diuretic medication. It can be used to treat fluid build-up due to liver disease or kidney disease. It is also used to reduce risk of disease progression, hospitalization, and death due to some types of heart failure. Other uses include acne and excessive hair growth in women, low blood potassium that does not improve with supplementation, high blood pressure that is difficult to treat, and early puberty in boys. It is also used to block the effects of testosterone as a part of feminizing hormone therapy. Spironolactone is usually available in tablets, taken by mouth, though topical forms are also available. Common side effects include electrolyte abnormalities, particularly high blood potassium, nausea, vomiting, headache, rashes, and a decreased desire for sex. In those with liver or kidney problems, extra care should be taken. If taken during pregnancy, some animal studies suggest that spironolactone may affect the development of sex organs in babies. While this has not occurred in the few human studies available, women who are pregnant or considering pregnancy should discuss spironolactone use with their doctor due to the theoretical risk. Spironolactone is a steroid that blocks the effects of the hormones aldosterone, and to a lesser degree, testosterone, causing some estrogen-like effects. Spironolactone belongs to a class of medications known as potassium-sparing diuretics. Spironolactone was discovered in 1957, and was introduced in 1959.
aa + ATP ⟶ aa-AMP + PPi aa-AMP + tRNA ⟶ aa-tRNA + AMP The amino acid is coupled to the penultimate nucleotide at the 3′-end of the tRNA (the A in the sequence CCA) via an ester bond (roll over in illustration).
Sources: en.wikipedia.org
It is a solid form of creatine that contains one water molecule per creatine molecule in the crystal lattice. The hydrate water is part of the crystal structure rather than loose moisture. The term is often used for the common crystalline powder grade.
Creatine anhydrous lacks the water of crystallization and therefore contains a higher creatine fraction by mass. The monohydrate is more common in commerce and research because it is stable and easy to handle. The two forms are not identical in solid state, though both yield creatine when dissolved.
Creatine is the base molecule, while creatine monohydrate is a hydrate of that molecule. Once dissolved, the hydrate water becomes part of the solvent and free creatine is present. In casual usage the names are often shortened to creatine, but the solid forms differ.
Creatine is the base compound, while creatine monohydrate is a solid crystalline form that contains one water molecule per creatine molecule. Once dissolved, the monohydrate dissociates and releases creatine, which can participate in cellular energy metabolism. The monohydrate is the form most commonly used in research and commercial products.