The short version of LC-MS/MS fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-10-06 and is reviewed periodically as new material appears.
GW501516 acts as a selective agonist at PPARδ, a nuclear receptor that regulates transcription of genes involved in lipid handling and energy metabolism. Activation of PPARδ in preclinical models increases fatty acid oxidation, mitochondrial biogenesis, and exercise endurance in rodents. These effects have made the compound a subject of metabolic research and also a target for sport anti-doping rules. In humans, however, controlled studies are limited, and whether similar endurance or metabolic changes occur at tolerated exposures remains an open question. The receptor’s broad tissue distribution also means downstream effects may vary by organ and condition.
Detection of GW501516 in biological samples generally relies on liquid chromatography coupled with tandem mass spectrometry. Urine is a common matrix in anti-doping analysis, while blood or plasma may be used in research settings. Sample preparation can involve enzymatic hydrolysis, protein precipitation, or solid-phase extraction before instrumental analysis. Because the compound undergoes metabolism, assays may target the parent molecule, one or more metabolites, or both. Detection windows are not fixed; they depend on factors such as dose, route, individual metabolism, and assay sensitivity. Reference standards are required for accurate identification and quantification.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Visual description for typical solid reference material. |
| Solubility | Poorly soluble in water; soluble in DMSO | Solubility depends on solvent, purity, and form. |
| Storage | Cool, dry, protected from light | Long-term storage often uses low temperature and desiccant. |
| Common analytical method | LC-MS/MS | Used for detection and quantification in biological matrices. |
| Common synonyms | GW-501516; GW501516; endurobol | Naming varies among literature, vendors, and databases. |
In laboratory settings, cardarine is studied as a tool compound for probing PPARδ biology. Published experiments often use cell cultures, rodent models, or isolated tissues. Some investigations focus on metabolic effects, while others assess potential risks such as carcinogenicity observed in long-term animal studies. Because human trials are sparse, most knowledge comes from preclinical work and adverse event reports. Scientific literature frequently notes the gap between animal findings and human outcomes. The compound is not a dietary supplement and is not intended for human consumption.
Cardarine is a common name for GW501516, a synthetic compound developed in the 1990s through research collaborations involving GlaxoSmithKline. It belongs to a class of molecules known as peroxisome proliferator-activated receptor delta agonists. Early studies explored its effects on lipid metabolism and energy expenditure in animal models. The compound was never approved as a human medicine, and clinical development was discontinued. In the years since, it has appeared in fitness and bodybuilding communities as a performance-enhancing substance. Regulatory agencies classify it as an unapproved drug.
PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
Products sold as cardarine have been found to contain incorrect compounds, variable amounts, or no active ingredient at all. Independent testing is required to verify identity and purity. Common analytical approaches include high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance for structural confirmation. These methods can distinguish GW501516 from related PPAR agonists and from unrelated steroids. For regulators and researchers, such verification is central to interpreting both biological results and adverse event reports.
Cardarine is a common name for GW501516, a synthetic compound first described in the 1990s as a selective agonist of the peroxisome proliferator-activated receptor delta. It was studied in preclinical models for metabolic and cardiovascular conditions, but it has not been approved as a medicine in the United States, Europe, or other major jurisdictions. Retail products labeled as cardarine are generally research chemicals or supplements, not pharmaceutical formulations. Because human safety and efficacy data remain limited, regulatory agencies treat it as an unapproved substance rather than a therapeutic product.
Sporting authorities added GW501516 to prohibited lists after it appeared in athlete samples and online markets. The World Anti-Doping Agency classifies it as a hormone and metabolic modulator, and its use can lead to an anti-doping rule violation. Some early laboratory work suggested effects on fatty acid oxidation and endurance-related metabolism in animals, but those findings do not establish safe or effective use in people. Reports of adverse events in humans are scarce and often anecdotal, which complicates risk assessment.
The pharmacological interest in cardarine centers on PPARδ activation and its downstream effects on lipid handling and mitochondrial function. In animal studies, PPARδ agonists have been associated with changes in exercise endurance and fatty acid utilization, though results vary by model and protocol. Human data remain sparse, and the absence of large controlled trials limits conclusions about efficacy. Researchers often describe the compound as a tool for probing PPARδ biology rather than a proven therapeutic agent.
Safety discussions about cardarine frequently cite rodent carcinogenicity findings reported in the 2000s. In those studies, treated animals developed tumors at multiple sites, leading sponsors to discontinue clinical development. The relevance of these findings to humans has not been resolved, but they are a major reason the compound is not approved. Current literature emphasizes uncertainty about long-term effects and the risks of unregulated use. Regulators and health agencies have not established a safe human exposure level.
Cardarine is a synthetic compound also known as GW501516, GW-501516, and sometimes endurobol. It was developed as a selective agonist of peroxisome proliferator-activated receptor delta, a nuclear receptor involved in fatty acid oxidation and energy metabolism. The compound was studied in preclinical models for metabolic and cardiovascular conditions, but it did not become a marketed human medicine. In regulatory and anti-doping contexts, it is treated as a prohibited substance rather than a licensed medicine.
=== Intellectual property issues === Ayahuasca has stirred debate regarding intellectual property protection of traditional knowledge. In 1986 the US Patent and Trademarks Office (PTO) allowed the granting of a patent on the ayahuasca vine B. caapi. It allowed this patent based on the assumption that ayahuasca's properties had not been previously described in writing. Several public interest groups, including the Coordinating Body of Indigenous Organizations of the Amazon Basin (COICA) and the Coalition for Amazonian Peoples and Their Environment (Amazon Coalition) objected. In 1999 they brought a legal challenge to this patent which had granted a private US citizen "ownership" of the knowledge of a plant that is well-known and sacred to many Indigenous peoples of the Amazon, and used by them in religious and healing ceremonies. Later that year the PTO issued a decision rejecting the patent, on the basis that the petitioners' arguments that the plant was not "distinctive or novel" were valid; however, the decision did not acknowledge the argument that the plant's religious or cultural values prohibited a patent. In 2001, after an appeal by the patent holder, the US Patent Office reinstated the patent, albeit to only a specific plant and its asexually reproduced offspring. The law at the time did not allow a third party such as COICA to participate in that part of the reexamination process. The patent, held by American entrepreneur Loren Miller, expired in 2003.
== In the aquarium == The royal angelfish can be challenging to keep in captivity, a healthy specimen that is given the right environment will likely start feeding within days when fed a variety of live, frozen, and flake or freeze-dried foods to entice satiety. A hostile environment will directly counter acclimation and feeding efforts. As such, large angelfish, triggerfish, puffers, as well some overly aggressive clownfish and surgeonfish should be avoided.
== Further reading == Jackie Y. Ying (2001). Nanostructured Materials. Academic Press. pp. 5–. ISBN 978-0-12-744451-2. Nanoparticles Used in Solar Energy Conversion (ScienceDaily). "Nanoparticles: An occupational hygiene review" Archived 24 September 2015 at the Wayback Machine by RJ Aitken and others. Health and Safety Executive Research Report 274/2004 "EMERGNANO: A review of completed and near completed environment, health and safety research on nanomaterials and nanotechnology" by RJ Aitken and others. High transmission Tandem DMA for nanoparticle studies by SEADM, 2014.
== Peptides and proteins == A number of algorithms for estimating isoelectric points of peptides and proteins have been developed. Most of them use Henderson–Hasselbalch equation with different pK values. For instance, within the model proposed by Bjellqvist and co-workers, the pKs were determined between closely related immobilines by focusing the same sample in overlapping pH gradients. Some improvements in the methodology (especially in the determination of the pK values for modified amino acids) have been also proposed. More advanced methods take into account the effect of adjacent amino acids ±3 residues away from a charged aspartic or glutamic acid, the effects on free C terminus, as well as they apply a correction term to the corresponding pK values using genetic algorithm. Other recent approaches are based on a support vector machine algorithm and pKa optimization against experimentally known protein/peptide isoelectric points. Moreover, experimentally measured isoelectric point of proteins were aggregated into the databases. Recently, a database of isoelectric points for all proteins predicted using most of the available methods had been also developed. In practice, a protein with an excess of basic aminoacids (arginine, lysine and/or histidine) will bear an isoelectric point roughly greater than 7 (basic), while a protein with an excess of acidic aminoacids (aspartic acid and/or glutamic acid) will often have an isoelectric point lower than 7 (acidic).
Sources: en.wikipedia.org
The use of concrete in construction grew rapidly from 1850 onward, and was soon the dominant use for cements. Thus Portland cement began its predominant role. Isaac Charles Johnson further refined the production of meso-Portland cement (middle stage of development) and claimed he was the real father of Portland cement. Setting time and "early strength" are important characteristics of cements. Hydraulic limes, "natural" cements, and "artificial" cements all rely on their belite (2 CaO · SiO2, abbreviated as C2S) content for strength development. Belite develops strength slowly. Because they were burned at temperatures below 1,250 °C (2,280 °F), they contained no alite (3 CaO · SiO2, abbreviated as C3S), which is responsible for early strength in modern cements. The first cement to consistently contain alite was made by William Aspdin in the early 1840s: This was what we call today "modern" Portland cement. Because of the air of mystery with which William Aspdin surrounded his product, others (e.g., Vicat and Johnson) have claimed precedence in this invention, but recent analysis of both his concrete and raw cement have shown that William Aspdin's product made at Northfleet Cement Works, Kent was a true alite-based cement. However, Aspdin's methods were "rule-of-thumb": Vicat is responsible for establishing the chemical basis of these cements, and Johnson established the importance of sintering the mix in the kiln.
== Diagnosis == Protein function tests that demonstrate a reduce in chorein levels and also genetic analysis can confirm the diagnosis given to a patient. For a disease like this it is often necessary to sample the blood of the patient on multiple occasions with a specific request given to the haematologist to examine the film for acanthocytes. Another point is that the diagnosis of the disease can be confirmed by the absence of chorein in the western blot of the erythrocyte membranes.
=== Localization of VIP === VIP is highly localised in lungs (70%) and binds with alveolar type II (AT II) cells via VPAC1. The biological (vasodilator) activity of vasoactive intestinal peptide (VIP) was discovered in the lungs before the peptide was isolated and chemical identity characterized from intestine. VIP levels are also considerably high in the brain and the gut. It is localized in key sites in the lung, has potent activities on its major functions, and appears to play an important role in pulmonary physiology and disease. The principal localization of VIP-containing neurons in the tracheobronchial tree is in the smooth muscle layer, around submucosal mucous glands and in the walls of pulmonary and bronchial arteries. Immunoreactive VIP is also present in neuronal cell bodies forming microglia that provide a source of intrinsic innervation of pulmonary structures.
Originally, René Just Haüy considered that each chemical compound had a characteristic crystalline form. However, based on his 1808 work with aragonite and his earlier studies of calcite, which are two different forms of calcium carbonate (CaCO3), Haüy had to concede that substances with the same chemical composition but different molecular arrangements could have different crystalline forms. In 1819 Eilhard Mitscherlich discovered the law of isomorphism which states that compounds which contain the same number of atoms, and have similar structures, tend to exhibit similar crystal forms. Mitscherlich carried out the first systematic research on the dependence of crystal forms on their chemical nature. The discovery of isomorphism was the first major step in chemical crystallography and Emil Wohlwill regarded Mitscherlich's work on isomorphism as a milestone in the history of the atomic-molecular theory. The discovery of the phenomena of isomorphism and polymorphism dealt a clear blow to Haüy's crystal structure theory. Mitscherlich's findings were a central consideration of the atomic weight determinations in 1819 by Jöns Jacob Berzelius, a leading proponent of Dalton's atomic theory. Berzelius classified minerals by their chemical composition rather than by their crystal morphology, as was the established practice. Mitscherlich's research, together with the work of Alexis Thérèse Petit and Pierre-Louis Dulong that heat capacities of solids vary with temperature and inversely with atomic weight, led Berzelius to declare them as a positive confirmation of the atomic theory.
=== 23 March === Dmitry Medvedev, former president of Russia and current deputy chairman of Russia's security council, threatened war against any country, if their officials attempted to arrest Putin on the ICC warrant, during a future state visit. He also described the ICC as a "legal nonentity that had never done anything significant". He also threatened that Russia would in that case possibly attack the International Criminal Court with hypersonic missiles that would be launched from a ship in the North Sea. Medvedev also reaffirmed his previous warnings that the chance of nuclear war increases each time the western nations send military aid to Ukraine. Sweden approved 6.2 billion kronor worth of military aid to Ukraine which included vehicles and ammunition.
Sources: en.wikipedia.org
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.
Most methods use liquid chromatography with tandem mass spectrometry. Urine is common in anti-doping testing, and blood or plasma may be used in research.
Typical guidance is cool, dry, dark storage, often at low temperature and with desiccant. Stability data are limited, so storage conditions should be verified for each batch or supplier.
Legal status varies by country. It is not approved as a medicine, and it is prohibited in sport. Some jurisdictions restrict import, sale, or possession.