If you have been reading about Moisture content and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-07-31. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Sourcing and verification of creatine monohydrate involve both manufacturing origin and third-party testing. Industrial production commonly starts with sarcosine and cyanamide, followed by crystallization to obtain the monohydrate. Some products are derived from animal sources, while others are synthesized from non-animal precursors. Certificates of analysis report assay, heavy metals, and microbial limits. Regulations differ by country: in the United States it is sold as a dietary supplement, whereas in the European Union it falls under food supplement rules.
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.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | 15–25 °C | Cool, dry, away from moisture |
| Relative humidity | < 50% | High humidity promotes degradation |
| Primary degradation product | Creatinine | Formed via cyclization, especially in solution |
| Common analytical method | HPLC-UV | Often at 210 nm; also titration or NMR |
| Shelf life (solid) | 2–3 years | When kept sealed and dry; varies by manufacturer |
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.
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.
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.
Commercial creatine monohydrate is typically manufactured through chemical synthesis, often starting from sarcosine and cyanamide. The resulting material is crystallized, washed, and dried to a specified hydrate content. Finished lots are tested for identity, purity, moisture, and heavy metals before release. Because the compound can cyclize to creatinine under heat or prolonged storage in solution, manufacturers control temperature and humidity during processing. The solid itself is relatively stable when kept dry and sealed, but moisture uptake can cause caking and complicate accurate assay.
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.
Manufacturing processes can leave trace amounts of dicyandiamide, creatinine, or residual solvents, depending on the synthetic route and purification steps. Heavy metals, arsenic, and microbial contamination are also monitored for food or pharmaceutical grades. Particle size distribution can affect dissolution behavior and blending uniformity, so it may be specified for certain applications. Analytical results are reported on a dry basis or as-is basis, and the difference matters when comparing certificates of analysis. Open questions remain about how minor impurities influence long-term stability under varied storage conditions.
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.
=== Surgery === A randomized controlled trial found that surgery "reduces the recurrence of ulcers at four years and results in a greater proportion of ulcer free time". Local anaesthetic endovenous surgery using the thermoablation (endovenous laser ablation or radiofrequency), perforator closure (TRLOP) and foam sclerotherapy showed an 85% success rate of healing, with no recurrence of healed ulcers at an average of 3.1 years, and a clinical improvement in 98% in a selected group of venous leg ulcers. Endovenous ablation, in combination with compression, on superficial venous incompetence has been shown (high-quality evidence) to improve leg ulcer healing when compared to compression alone. The use of subfascial endoscopic perforator surgery is uncertain in the healing of venous ulcers.
=== 1990 === January 13, 1990 – The Stasi, the secret police of East Germany, is dissolved. January 22, 1990 – the League of Communists of Yugoslavia, the ruling party of the Socialist Federal Republic of Yugoslavia, is dissolved during its congress, ending the one party system in the country. February 1, 1990 – StB, the secret police of Czechoslovakia is dissolved. March 15, 1990 – Inauguration of Gorbachev as the first president of the Soviet Union. April 12, 1990 – The Socialist Republic of Slovenia within Yugoslavia holds its first multi-party elections. April 22–23 and May 6–7, 1990 – the Socialist Republic of Croatia within Yugoslavia holds its first multi-party elections. April 25, 1990 – Violeta Chamorro is sworn in as president of Nicaragua, ending the Sandinista rule and the Contras insurgency. May 22, 1990 – South and North Yemens are unified. June 8, 1990 – the Message from Turnberry, described as the "first official recognition of the end of the Cold War", is issued. July 5–6, 1990 – NATO holds its 11th summit in London. July 13, 1990 – The 28th Congress of the Communist Party of the Soviet Union announces the end of its monopoly of power. August 2, 1990 – Beginning of Gulf War. September 9, 1990 – Helsinki Summit between Bush and Gorbachev. September 12, 1990 – The Treaty on the Final Settlement with Respect to Germany is signed in Moscow. October 3, 1990 – Official reunification of Germany. November 6, 1990 – Hungary become the first Soviet Bloc country to join the Council of Europe.
=== Europe === Hardtack, baked with or without the addition of fat, was and still is a staple in Russian military rations, especially in the Navy, as infantry traditionally preferred simple dried bread when long shelf life was needed. Called galeta (галета) in Russian, it is usually somewhat softer and more crumbly than traditional hardtack, as most varieties made in Russia include at least some fat or shortening, making them closer to saltine crackers. One such variety, khlyebtsy armyeyskiye (хлебцы армейские), or "army crackers", is included in Russian military rations. Other brands enjoy significant popularity among the civilian population as well, both among campers and the general populace. In Genoa, hardtack was and still is a traditional addition to a fish and vegetable salad called cappon magro. In Germany, hardtack is included in every military ration and colloquially known as Panzerplatten (armor plates) or Panzerkekse (armor cookies/tank cookies). Due to conscription for many years a large part of the male population knew about them from their service and thus they became somewhat popular even in civilian use. The company that makes them also sells them unaltered to the civilian market. They are said to have many properties, some jokingly assigned, such as the ability to combine them with standard issue shoe polish to create a flammable device, or to glue them onto vehicles to increase their armor protection.
== External links == AccelrysPKA — Accelrys CHARMm based pKa calculation H++ — Poisson–Boltzmann based pKa calculations MCCE2 — Multi-Conformation Continuum Electrostatics (Version 2) Karlsberg+ — pKa computation with multiple pH adapted conformations PETIT — Proton and Electron TITration GMCT — Generalized Monte Carlo Titration DEPTH web server — Empirical calculation of pKa values using Residue Depth as a major feature
Sources: en.wikipedia.org
There is great overlap in what 1H MRS and 13C MRS can obtain spectra-wise and large reason, combined with 1H MRS's high sensitivity, why 13C MRS has never seen wide application like 1H MRS. See also Hyperpolarized carbon-13 MRI. 23Sodium Magnetic Resonance Spectroscopy Sodium NMR is infamous for its low sensitivity (9.2% relative to proton sensitivity) and low SNR because of its low sodium concentration (30 - 100 mM), especially compared to protons (40 - 50 M). However, interest in sodium NMR has been reinspired by recent significant gains in SNR at high magnetic fields, along with improved coil designs and optimized pulse sequences. There is much hope for sodium NMR's clinical potential because the detection of abnormal intracellular sodium in vivo may have significant diagnostic potential and reveal new insights into tissue electrolysis homeostasis. 19Fluorine Magnetic Resonance Spectroscopy Fluorine NMR has high sensitivity (82% relative to proton sensitivity) and 100% natural abundance. However, no endogenous 19F containing compounds are found in biological tissues and thus the fluorine signal comes from an external reference compound. Because19F is not found in biological tissues, 19F does not have to deal with interference from background signals like in vivo 1H MRS does with water, making it especially powerful for pharmacokinetic studies. 1H MRI provides the anatomical landmarks, while 19F MRI/MRS allows us to follow and map the specific interactions of specific compounds.
== Mistaken portrait == For two centuries, until the discovery of the error in 2005, books, paintings and articles had incorrectly shown a profile portrait of the obscure French politician Louis Legendre (1752–1797) as a portrait of the mathematician. The error arose from the fact that the sketch was labelled simply "Legendre" and appeared in a book along with contemporary mathematicians such as Lagrange. One of only two known portraits of Legendre, rediscovered in 2008, is found in the 1820 book Album de 73 portraits-charge aquarellés des membres de I'Institut, a book of caricatures of seventy-three members of the Institut de France in Paris by the French artist Julien-Léopold Boilly as shown below. The other portrait is from the book Le Panthéon scientifique de la tour Eiffel.
I wish that all nations may recover and retain their independence; that those which are overgrown may not advance beyond safe measure of power, that a salutary balance may ever be maintained among nations and that our peace, commerce, and friendship, may be sought and cultivated by all.... Not in our day, but at no distant one, we may shake a rod over the heads of all, which may make the stoutest of them tremble. In 1942, Robert Strausz-Hupé found that it "is in the interests of the United States no less than that of humanity" that the United States should be the only one "geographical power nucleus" from which a "balancing and stabilizing" power of arbiter be exercised. This "will pave the way for a new and universal order." Writing the same year in Life magazine, Joseph Thorndike tells about "many observers" seeking "preponderant power in the postwar world" to replace balance of power:
Sources: en.wikipedia.org
Yes, especially when exposed to moisture or heat, where it converts to creatinine. In dry, sealed containers at room temperature, degradation is slow and the product may remain within specification for two to three years.
Common methods include high-performance liquid chromatography, titration, and nuclear magnetic resonance spectroscopy. These techniques quantify the parent compound and detect related substances such as creatinine.
Keep the powder in a tightly sealed container in a cool, dry place, ideally between 15 and 25 degrees Celsius with low humidity. Avoid storing aqueous solutions for extended periods because degradation occurs faster in solution.
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.