The short version of HPLC assay fits in a sentence. The long version — which is the one that helps — is below.
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Several creatine forms are sold, including monohydrate, anhydrous, hydrochloride, nitrate, citrate, and blends. Once dissolved, these forms deliver creatine, but they differ in molar mass, solubility, counterions, and water content. Creatine monohydrate has the largest body of published human data among these forms. Questions remain about whether any alternative form offers meaningful advantages in absorption, tolerability, or tissue uptake under practical conditions. The hydrate form's lower creatine content by mass is a compositional fact, not a statement about effectiveness.
Creatine monohydrate is a crystalline compound formed when one molecule of creatine associates with one molecule of water in the solid lattice. Its molecular formula is C4H11N3O3, and its molar mass is about 149.15 grams per mole. The material appears as a white, odorless powder that dissolves sparingly in water at room temperature. The monohydrate designation distinguishes it from anhydrous creatine, which lacks the bound water and has a lower molar mass. This hydrate is the most common commercial form of creatine used in nutritional and research settings.
Creatine is synthesized endogenously in humans, mainly in the liver, kidney, and pancreas, from the amino acids arginine, glycine, and methionine. Skeletal muscle stores much of the body's creatine, where it participates in the phosphocreatine system that buffers adenosine triphosphate during short, intense contractions. Dietary sources include meat and fish, so omnivorous diets provide additional creatine beyond endogenous production. Supplemental creatine monohydrate supplies the same molecule found in food and tissues, not a distinct drug or hormone. Research interest centers on its role in cellular energy transfer and its effects on muscle and other tissues.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical formula | C4H11N3O3 | Often written C4H9N3O2·H2O |
| Molar mass | 149.15 g/mol | Anhydrous creatine is 131.13 g/mol |
| Appearance | White crystalline powder | Odorless, fine or granular |
| Water solubility | About 13 g/L at 25 °C | Low; increases with temperature |
| Common synonyms | Creatine hydrate; N-carbamimidoylsarcosine monohydrate | CAS 6020-87-7 |
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.
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.
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.
The American Society for Pharmacology and Experimental Therapeutics (ASPET) is a scientific society founded in late 1908 by John Jacob Abel of Johns Hopkins University (also the founder of the American Society for Biochemistry and Molecular Biology), with the aim of promoting the growth of pharmacological research. Many society members are researchers in basic and clinical pharmacology who help develop disease-fighting medications and therapeutics. ASPET is one of the constituent societies of the Federation of American Societies for Experimental Biology (FASEB). The society's headquarters are in Rockville, MD. The current president is Michael F. Jarvis.
The G protein-coupled receptor kinases (GRKs) are protein kinases that phosphorylate only active GPCRs. G-protein-coupled receptor kinases (GRKs) are key modulators of G-protein-coupled receptor (GPCR) signaling. They constitute a family of seven mammalian serine-threonine protein kinases that phosphorylate agonist-bound receptor. GRKs-mediated receptor phosphorylation rapidly initiates profound impairment of receptor signaling and desensitization. Activity of GRKs and subcellular targeting is tightly regulated by interaction with receptor domains, G protein subunits, lipids, anchoring proteins and calcium-sensitive proteins. Phosphorylation of the receptor can have two consequences:
Insoluble accumulations of β-amyloid peptide in brain regions related to memory and cognition are a defining characteristic of Alzheimer's disease (AD). SNX8 has a neuroprotective role related to AD: it enhances the non-amyloidogenic APP pathway and, hence, reduces the Aβ plaques and deposit accumulations and suppresses cognitive impairment caused by AD. Some studies found that SNX8 levels were drastically lower in patients with AD. Furthermore, it has been demonstrated that SNX8 overexpression mediated by adeno-associated virus (AVV) reduced Aβ levels and reversed cognitive impairment in AD mice. It is also important mentioning that a pair of polymorphisms (rs2286206 and rs10249052) within the human SNX8 gene locus have also been associated with late-onset AD.
== Active Ingredients: Weight Loss Efficacy & Potential Side Effects Caffeine === The caffeine content in the daily recommended dose of Dexatrim products ranges from 50–400 mg per day. There are a number of studies showing that caffeine has a short-term stimulatory effect on basal metabolic rate. However, in 1992, in a double-blind placebo controlled study, caffeine (at a dose of 200 mg daily) was found to be no more effective in promoting weight loss than a placebo. Potential side effects of caffeine may include insomnia, anxiety, gastrointestinal discomfort, diarrhea, headaches and abnormal heart beat. Green tea extract is currently used for a variety of conditions including improving mental alertness and aiding in weight loss. There is currently insufficient data to determine the efficacy of green tea extract in aiding weight loss. In addition to the potential side effects from the caffeine content in green tea extract, there is some risk of liver problems associated with green tea extract consumption. Liver problems have not been observed with the use of green tea in beverages.
Blastula-stage cells can behave as pluripotent stem cells in many species. Pluripotent stem cells are the starting point to produce organ specific cells that can potentially aid in repair and prevention of injury and degeneration. Combining the expression of transcription factors and locational positioning of the blastula cells can lead to the development of induced functional organs and tissues. Pluripotent Xenopus cells, when used in an in vivo strategy, were able to form into functional retinas. By transplanting them to the eye field on the neural plate, and by inducing several mis-expressions of transcription factors, the cells were committed to the retinal lineage and could guide vision based behavior in the Xenopus. Polarity in embryogenesis Diploblasty Triploblasty
Sources: en.wikipedia.org
Arrestins are elongated molecules, in which several intra-molecular interactions hold the relative orientation of the two domains. Unstimulated cell arrestins are localized in the cytoplasm in a basal inactive conformation. Active phosphorylated GPCRs recruit arrestin to the plasma membrane. Receptor binding induces a global conformational change that involves the movement of the two arrestin domains and the release of its C-terminal tail that contains clathrin and AP2 binding sites. Increased accessibility of these sites in receptor-bound arrestin targets the arrestin-receptor complex to the coated pit. Arrestins also bind microtubules (part of the cellular skeleton), where they assume yet another conformation, different from both free and receptor-bound form. Microtubule-bound arrestins recruit certain proteins to the cytoskeleton, which affects their activity and/or redirects it to microtubule-associated proteins. Arrestins shuttle between cell nucleus and cytoplasm. Their nuclear functions are not fully understood, but it was shown that all four mammalian arrestin subtypes remove some of their partners, such as protein kinase JNK3 or the ubiquitin ligase Mdm2, from the nucleus. Arrestins also modify gene expression by enhancing transcription of certain genes.
As there are two carbon atoms available for substitution, β-amino acids have four sites (chirality included; as opposed to two in α-amino acids) for attaching the organic residue group. Accordingly, two main types β-amino acids exist differing by which carbon the residue is attached to: ones with the organic residue (R) next to the amine are called β3 and those with position next to the carbonyl group are called β2. A β-peptide can consist of only one kind of these amino acids (β2-peptides and β3-peptides), or have a combination of the two. Furthermore, a β-amino acid can form a ring using both of its sites and also be incorporated into a peptide. β-Amino acids have been prepared by many routes, including some based on the Arndt-Eistert synthesis.
Iron-sulfur protein NUBPL (IND1) also known as nucleotide-binding protein-like (NUBPL), IND1 homolog, Nucleotide-binding protein-like or huInd1 is an iron-sulfur (Fe/S) protein that, in humans, is encoded by the NUBPL gene, located on chromosome 14q12. It has an early role in the assembly of the mitochondrial complex I assembly pathway. NUBPL is located on the q arm of chromosome 14 in position 12 and has 18 exons. The NUBPL gene produces a 5.9 kDa protein composed of 54 amino acids. The structure of the protein includes a presumed iron-sulfur binding (CxxC) signature, a nucleotide-binding domain which has been highly conserved, and a mitochondrial targeting sequence in the N-terminal. NUBPL is required for the assembly of complex I, which is composed of 45 evolutionally conserved core subunits, including both mitochondrial DNA and nuclear encoded subunits. One of its arms is embedded in the inner membrane of the mitochondria, and the other is embedded in the organelle. The two arms are arranged in an L-shaped configuration. The total molecular weight of the complex is 1MDa.
China is the main supplier of wolfberry products globally, with 2023 production derived from a cultivation area of 325,000 mu – about 21,667 ha (53,540 acres) – creating a national wolfberry economy of 29 billion yuan (approximately US $4.2 billion). Some 61% of commercially produced wolfberries in China comes from L. barbarum plantations in the Ningxia region, mainly in Zhongning County. Goji cultivation also occurs in Gansu, Qinghai Province, and the Haixi Mongol and Tibetan Autonomous Prefecture. The main berry products for export are manufactured beverages, juice concentrate, dried berries, snacks, and freeze-dried juice powder and berries. Ningxia goji has been cultivated along the fertile floodplains of the Yellow River over centuries. The region has developed an industrial association of growers, processors, marketers, and scholars of wolfberry cultivation to promote the berry's commercial and export potential. Ningxia goji berries, the variety used by practitioners of traditional Chinese medicine, are celebrated annually with a festival.
Sources: en.wikipedia.org
Binding sites can be characterized also by their structural features. Single-chain sites (of "monodesmic" ligands, μόνος: single, δεσμός: binding) are formed by a single protein chain, while multi-chain sites (of "polydesmic" ligands, πολοί: many) are frequent in protein complexes, and are formed by ligands that bind more than one protein chain, typically in or near protein interfaces. Recent research shows that binding site structure has profound consequences for the biology of protein complexes (evolution of function, allostery).
Agonists PACAP-38 (endogenous peptide agonist, full length version) - also activates other receptors VIP, GPR55 and MRGPRX2 and the Secretin receptor. PACAP-27 (endogenous peptide agonist, shorter fragment which retains activity) Antagonists PACAP(6-38) - N-terminal truncated version of the endogenous peptide agonist which acts as a potent PAC1 antagonist BAY 2686013 PA-915 "VIP and PACAP Receptors: PAC1". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. Human ADCYAP1R1 genome location and ADCYAP1R1 gene details page in the UCSC Genome Browser. This article incorporates text from the United States National Library of Medicine, which is in the public domain.
Paulovich is a Professor in Clinical Research, an Aven Foundation Endowed Chair, and the Director of Early Detection Initiative at the Fred Hutchinson Cancer Research Center. She was inducted to the American Society for Clinical Inviestigation in 2012. Paulovich is an expert in proteomics. Her targeted proteomics method uses multiple reaction monitoring mass spectrometry to target cancer biomarkers with ongoing clinical trials, and was named Method of the Year in 2012 by Nature Methods. She founded Precision Assays in 2016, whose rights to targeted assays were acquired by CellCarta in 2022. 2014 Life Science Innovation Northwest Woman to Watch in Life Science Award 2015 Human Proteome Organization (HUPO) Distinguished Achievement in Proteomic Sciences Award Identification and use of biomarkers for detection and quantification of the level of radiation exposure in a biological sample (2011) US 20130052668 A1 Compositions and methods for reliably detecting and/or measuring the amount of a modified target protein in a sample (2011) US 20130052669 A1
A chromogranin A-derived antifungal peptide (CGA 47–66, chromofungin) when embedded on a surface has been shown to have antifungal activity by interacting with the fungal membrane and thereby penetrating the cell. Additionally, in vitro studies have demonstrated that such an antifungal coating can inhibit the growth of yeast Candida albicans by 65% and completely stop the proliferation of filamentous fungus Neurospora crassa. Copper and copper alloy surfaces have demonstrated a die-off of Aspergillus spp., Fusarium spp., Penicillium chrysogenum, Aspergillus niger and Candida albicans fungal spores. Hence, the potential to help prevent the spread of fungi that cause human infections by using copper alloys (instead of non-antifungal metals) in air conditioning systems is worthy of further investigation. The physical topology of a surface will determine the viable environment for bacteria. It may affect a microbe's ability to adhere to its surface. Textile surfaces tend to be very easy for microbes to adhere to due to the abundance of interstitial spacing between fibers.
Antimicrobial peptides have been used as therapeutic agents; their use is generally limited to intravenous administration or topical applications due to their short half-lives. As of January 2018 the following antimicrobial peptides were in clinical use: Bacitracin for pneumonia, topical Boceprevir, Hepatitis C (oral, cyclic peptide) Dalbavancin, bacterial infections, IV Daptomycin, bacterial infections, IV Enfuvirtide, HIV, subcutaneous injection Oritavancin, bacterial infections, IV Teicoplanin, bacterial infections, IV Telaprevir, Hepatitis C, oral cyclic peptide Telavancin, bacterial infection, IV Vancomycin, bacterial infection, IV. AMPs have been observed having functions other than bacterial and fungal killing. These activities include antiviral effects , but also roles in host defence such as anticancer functions and roles in neurology. This has led to a movement for re-branding AMPs as "Host-defence peptides" to encompass the broad scope of activities AMPs can have.
Sources: en.wikipedia.org
It is the hydrated crystalline form of creatine, containing one bound water molecule per creatine unit. The compound is commonly used as a nutritional ingredient and as a research material.
Yes, endogenous synthesis occurs mainly in the liver, kidney, and pancreas. Meat and fish also contribute creatine to the diet.
Other forms contain creatine paired with different counterions or lacking water, so their mass and solubility differ. After dissolution, creatine itself is the shared active molecule.
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.