If you have been reading about Karl Fischer titration 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 2025-11-28. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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 |
|---|---|---|
| Purity (typical) | ≥99% by HPLC | Supplement and pharmacopeial grades vary |
| Water content | ≈12.1% theoretical | Measured by Karl Fischer titration |
| Creatinine limit | Often ≤0.1% in pharmacopeial grade | Supplement specifications may differ |
| Storage conditions | 15–25 °C, low humidity | Away from heat and acidic environments |
| Common analytical methods | HPLC–UV, NMR, FTIR, Karl Fischer | Used for identity, assay, and water content |
Silicone gel sheeting (SGS) has been an effective reductive and preventive scar therapy since 1980. It was first discovered to be used in treating scars by Perkins in Australia and New Zealand, and first discussed in the thesis of Karen Quinn, a British biomedical engineering student, in 1985. It is now considered the first-line prevention and treatment for hypertrophic and keloid scars by occlusion and then hydration of the scar tissue. Silicone gel is made of medical-grade silicone polymers. Silicone gel sheet consists of a soft, semi-occlusive sheet and a membrane that increases the durability of the sheet. The sheet has a solid rubber-like appearance. Although the mechanism of action of silicone gel sheeting remains partially unknown, its efficacy is confirmed by many clinical trials, and is similar to silicone gel.
=== Absolute glaucoma === Absolute glaucoma (H44.5) is the end stage of all types of glaucoma. The eye has no vision, absence of pupillary light reflex and pupillary response, and has a stony appearance. Severe pain is present in the eye. The treatment of absolute glaucoma is a destructive procedure, like cyclocryoapplication, cyclophotocoagulation, or injection of 99% alcohol.
=== Immune cells and inflammatory signaling === Macrophages present in the lesion environment differentiate into Multinucleated Giant Cells after prolonged activation. Secreted matrix metalloproteinases degrade collagen and fuel necrobiosis in response to immune activation. T cells, prominent in NL (Th-1 type cytokines) inhibit healing by the production of IFN-γ, suppressing M2 repair. These factors suggest a link to autoimmune conditions, as these factors explain a pro-inflammatory feedback loop.
=== Multidisciplinary approach === Given the systemic nature of many autoimmune disorders, a multidisciplinary approach may be necessary for their diagnosis and management. This can involve rheumatologists, endocrinologists, gastroenterologists, neurologists, dermatologists, and other specialists, depending on the organs or systems affected by the disease. In summary, the diagnosis of autoimmune disorders is a complex process that requires a thorough evaluation of clinical, laboratory, and imaging data. Due to the diverse nature of these diseases, an individualized approach, often involving multiple specialists, is crucial for an accurate diagnosis.
In the brain, hyaluronan serves as the primary component of the extracellular matrix, contributing to both structural integrity and signaling functions. High-molecular-weight hyaluronan forms a diffusional barrier that regulates local extracellular diffusion. When the ECM undergoes degradation, hyaluronan fragments are released into the extracellular space, where they act as pro-inflammatory molecules, influencing immune cell responses, including those of microglia.
Sources: en.wikipedia.org
== Bibliography == Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8. Penneman, R. A. and Keenan T. K. The radiochemistry of americium and curium, University of California, Los Alamos, California, 1960 Wiberg, Nils (2007). Lehrbuch Der Anorganischen Chemie. De Gruyter. ISBN 978-3-11-017770-1.
The panel has come to some controversy, however; on July 20, 2010, one of the panelists was discovered to have been a paid speaker for GlaxoSmithKline, arousing questions of a conflict of interest. This panel member was one of the three who voted to keep Avandia on the market with no additional warning labels. In 2011 the FDA has decided on revising its prescribing information and medication guides for all rosilitazone containing medicines. The US label for rosiglitazone (Avandia, GlaxoSmithKline) and all rosiglitazone-containing medications (Avandamet and Avandaryl) now include the additional safety information and restrictions. The revised labels restrict use to patients already taking a rosiglitazone-containing medicine or to new patients who are unable to achieve adequate glycemic control on other diabetes medications and to those, who in consultation with their healthcare provider, have decided not to take Actos (pioglitazone) or other pioglitazone-containing medicines for medical reasons. In June 2013 an FDA Advisory Committee reviewed all available data, including a re-adjudicated RECORD trial, found no evidence of increased cardiovascular risk with Avandia, and voted to remove the restrictions on Avandia marketing in the United States. In November 2013, the US FDA removed these marketing restrictions on the product. Under the FDA's instruction, Avandia's maker, GlaxoSmithKline, had funded the Duke Clinical Research Institute to re-analyze the raw data from the study.
It is worth mentioning that the pharmacokinetics of quisqualic acid has not been extensively studied and there is sparse information available on its ADME process. Therefore, more research is needed to fully understand the metabolism of the acid in the body.
where K is the area of the quadrilateral and s is its semiperimeter. For a tangential quadrilateral with given sides, the inradius is maximum when the quadrilateral is also cyclic (and hence a bicentric quadrilateral). In terms of the tangent lengths, the incircle has radius
Antiemetics Azasetron Dolasetron Granisetron Ondansetron Palonosetron Tropisetron Gastroprokinetics and for IBS-D Alosetron Renzapride (partial) Ramosetron M1, the major active metabolite of mosapride Antidepressants Mianserin Mirtazapine Vortioxetine Antipsychotics Clozapine Olanzapine Quetiapine Antimalarials Chloroquine Mefloquine Quinine Other drugs Lamotrigine (epilepsy and bipolar disorder) Memantine (Alzheimer's disease) Metoclopramide (related to gastrointestinal tract and migraine) Zacopride (anxiolytic and nootropic) Phytochemicals Cannabidiol (CBD) Menthol Thujone Tetrahydrocannabinol (THC) Unused AS-8112 Cilansetron BRL-46470 Batanopride LY-278584 Tedatioxetine Tropanserin Zatosetron
Sources: en.wikipedia.org
The medication is used to treat clear cell renal cell carcinoma, the most common histological subtype. The treatment phase is continuing treatment beyond three months. The patient has been issued an authority prescription for pazopanib. The patient must have stable or responding disease according to the Response Evaluation Criteria In Solid Tumours (RECIST). This treatment must be the sole tyrosine kinase inhibitor subsidised for this condition. Pazopanib has also demonstrated initial therapeutic properties in patients with aggressive fibromatosis (desmoid tumor), ovarian and non-small cell lung cancer. However, plans to apply to the EMA for a variation to include advanced ovarian cancer have been withdrawn and a license will not be sought in any country.
===== Legal categorization and legal issues in a near future ===== Currently, both miRNA and SiRNA are currently chemically synthesized and so, are legally categorized inside EU and in USA as "simple" medicinal products. But as bioengineered siRNA (BERAs) are in development, these would be classified as biological medicinal products, at least in EU. The development of the BERAs technology raises the question of the categorization of drugs having the same mechanism of action but being produced chemically or biologically. This lack of consistency should be addressed.
=== Solvent extraction and complexation chemistry === The liquid-liquid extraction for the selective actinide partitioning (SANEX-like processes) consists of an organic phase, containing an extracting agent dissolved in a suitable solvent mixture, and an aqueous phase, containing the irradiated fuel dissolution in hot nitric acid. The two phases are vigorously mixed to promote the extraction kinetics. The centrifugation process is performed to favour the phase separation and the transfer of the formed complexes from the depleted aqueous phase (raffinate) into the organic phase (extract) where they result more soluble. This solvent separation can be performed by neutral extracting agents dissolved in the solvent. As can be seen in the equation, the solvating ligand (L) extracts the interested metal cation (M) together with its anion (A). The products of this reaction represent all the potential complexes that can form during an extraction process such as
Arias Navarro lacked a plan to reform the Franco regime so his government adopted the one presented by Fraga Iribarne which consisted of achieving a "liberal" democracy that would be comparable to that of the rest of Western European countries through a gradual and controlled process from the power of gradual changes to the "fundamental laws" of Franco. That is why it was also known as "reform in continuity" and its support base would be what was then called "sociological Francoism". With the democratic opposition it was not intended to negotiate or agree on any essential element of the process and from the elections would be excluded the "totalitarians", in reference to the communists. For its part, the PCE, then the main anti-Francoist opposition party, and the Junta Democrática, the political platform it had created in 1974, promoted a great mobilization against the "Francoist" monarchy. There was agitation in the universities, demonstrations were held to the cry of "Freedom and Amnesty", violently dissolved by the police, and a wave of strikes was unleashed, much greater than the already very important ones of 1974 and 1975.
Sources: en.wikipedia.org
A sealed container kept at room temperature and away from moisture is typical. Heat and humidity promote conversion to creatinine and can reduce assay values. Long-term storage under dry conditions helps maintain the original crystalline form.
Creatinine is a degradation product formed when creatine loses water and cyclizes. It can appear during storage, processing, or analysis if conditions are harsh. Quality specifications often set a maximum limit for creatinine to control purity.
No universal testing protocol applies across all markets. Some products follow pharmacopeial monographs, while others rely on manufacturer specifications and third-party certificates. Common tests include assay, water content, heavy metals, and microbial limits.
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.