LC-MS/MS raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-01-11 and is reviewed periodically as new material appears.
Regulatory treatment varies, but cardarine is not approved as a medicine. Sports authorities list GW501516 as a prohibited substance, and it is banned at all times under the World Anti-Doping Agency code. Many countries restrict sales for human consumption, while online vendors market it as a research chemical. Such products may lack purity data, and their actual contents can differ from the label. Purchasing or possessing cardarine may carry legal consequences depending on jurisdiction. The compound is not a dietary supplement ingredient in regulated markets.
Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
Laboratory detection of GW501516 commonly uses liquid chromatography coupled with tandem mass spectrometry. The method can identify the parent compound or its metabolites in urine and blood after sample cleanup. Protein precipitation, solid-phase extraction, or enzymatic hydrolysis may precede analysis, depending on the matrix. Reference standards are required for accurate quantification and confirmation. Because the compound is not approved, testing often occurs in anti-doping, forensic, or research settings rather than routine clinical care. Results are reported with limits of detection and quantification.
Stability of GW501516 depends on form, temperature, light exposure, and moisture. Solid reference material is typically stored frozen or refrigerated in a desiccator and protected from light. Solutions in organic solvents such as dimethyl sulfoxide are often kept frozen in aliquots to reduce freeze-thaw cycling. Aqueous solubility is low, so aqueous stock solutions can be difficult to prepare without cosolvents. Degradation may appear as changes in chromatographic purity or mass spectral signal. Stability studies are needed to establish shelf life for any specific preparation.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | GW501516; GW-1516; endurobol | GW501516 is the research code |
| Drug class | PPARδ agonist | Not a selective androgen receptor modulator |
| Molecular formula | C21H18F3NO3S2 | Established chemical formula |
| Molar mass | 453.5 g/mol | Calculated from the formula |
| Regulatory status | Prohibited in sport; not approved as medicine | Status varies by country |
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
Cardarine is not approved for human therapeutic use in any major jurisdiction. It appears on the World Anti-Doping Agency Prohibited List as a PPARδ agonist within the hormone and metabolic modulators category. Sports organizations test for it because it has been detected in athlete samples and seized products. Regulatory actions against marketed research chemical versions have occurred in several countries, though enforcement varies. Availability through unregulated channels complicates oversight.
Laboratory studies indicate that GW501516 activates PPARδ, a nuclear receptor involved in fatty acid oxidation and energy metabolism. In rodent experiments, treated animals often showed increased endurance and reduced fat mass. These effects were observed under controlled conditions and do not establish safe or effective use in humans. The exact dose-response relationship in humans remains poorly characterized. Species differences in metabolism can affect how results translate across animals and people.
Safety concerns emerged from long-term animal studies. In rodents given the compound for extended periods, researchers found an increased incidence of certain cancers, including liver and bladder tumors. These findings contributed to the discontinuation of clinical development. Whether similar risks apply to short-term or low-level exposure in humans is not established, and controlled human safety data are limited. The relevance of high-dose rodent carcinogenicity findings to human use remains a subject of debate.
Human trials of GW501516 were small and short in duration. They examined lipid levels, glucose handling, and other metabolic markers, but the programs were halted after the animal cancer findings. No approved therapeutic product exists, and published human data are insufficient for establishing long-term safety. Reports of use for athletic performance come mainly from non-clinical settings and cannot be verified through controlled trials. Independent testing of products sold as cardarine has found inconsistent purity and labeling.
Cardarine can be detected in biological samples and product materials using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method separates compounds by chromatography and identifies them by mass-to-charge transitions, allowing low-level detection in urine or blood. Sample preparation often involves enzymatic hydrolysis, solid-phase extraction, or protein precipitation. Certified reference materials and isotope-labeled internal standards improve quantification. Detection windows depend on metabolism, matrix, and assay sensitivity, so no single universal window applies.
Regulatory treatment of cardarine differs by context and jurisdiction. In competitive sport, the World Anti-Doping Agency lists PPARδ agonists, including GW501516, as prohibited at all times. Outside sport, it lacks approval as a prescription medicine in major drug markets, and products sold for human consumption may be treated as unapproved drugs. Some countries also restrict importation or sale through general consumer protection and medicines laws. These classifications affect availability, testing, and legal risk without establishing therapeutic value.
Because cardarine is not an approved medicine, no pharmacopeial monograph defines its identity, purity, or storage requirements. Laboratories typically rely on in-house methods and reference standards when testing materials labeled as GW501516. Certificates of analysis may report purity and identity for a specific batch, but their scope varies and they do not guarantee safety or legal status. Independent verification can include high-performance liquid chromatography, mass spectrometry, nuclear magnetic resonance, and elemental analysis. The distinction between research chemical labeling and human use is significant because quality standards and oversight differ.
In Sri Lanka, a Member of Parliament refers to a member of the Parliament of Sri Lanka (since 1978), the National State Assembly (1972–78) and the House of Representatives of Ceylon (1947–72), the lower house of the Parliament of Ceylon. Members are elected in a general elections or appointed from the national lists allocated to parties (and independent groups) in proportion to their share of the national vote at a general election. A candidate to become an MP must be a Sri Lankan citizen and can be a holder of dual-citizenship in any other country, be at least 18 years of age, and not be a public official or officeholder.
== Chondrocyte Primary Culture == Chondrocytes can be prepared by sequential enzymatic digestion of cartilage with Pronase and Collagenase and cultured in DMEM-F12 cell culture media. Transplantation of dedifferentiated chondrocytes often leads to the formation of fibrous tissue formation. Redifferentiation of dedifferentiated chondrocytes in the 3-D system (spheroid culture) restore morphological and functional properties.
Starmer pledges to give all veterans, young care leavers and victims of domestic abuse a "guaranteed roof over their head". Senedd members vote to withdraw proposals to require parties to ensure 50% of their candidates are women. 25 September – Unions win a nonbinding vote at the Labour Party Conference calling on the government to reverse its cuts to winter fuel payments. Former Conservative MP and government minister Michael Gove is appointed as editor of The Spectator, and will take up the post in early October. Conservative Senedd member Natasha Asghar is reprimanded by Senedd authorities for calling Wales' 20 mph speed limit a "blanket" policy on social media, while signing off a report advising her party to refrain from using the term. 26 September – Starmer and Foreign Secretary David Lammy hold their first meeting with Donald Trump, attending a two-hour dinner with the Republican presidential candidate in New York. Former Conservative Party chairwoman Baroness Saeeda Warsi resigns from the party in the House of Lords, saying it has lurched to the "far-right". 27 September – 2024 Scottish Conservatives leadership election: Russell Findlay is elected as the new leader of the Scottish Conservatives, succeeding Douglas Ross. The Senedd Commission forecasts it will need an extra £1.2m in 2025–26 to prepare for a larger Senedd at the 2026 election. 28 September – Rosie Duffield, MP for Canterbury, resigns from the Labour Party, citing what she describes as it "cruel" policies and Keir Starmer's "staggering hypocrisy" over his acceptance of gifts.
Sources: en.wikipedia.org
=== Poetic style and influences === Thomas's refusal to align with any literary group or movement has made him and his work difficult to categorise. However the formative influence of the modernist symbolist and surrealist movements has been discerned throughout his poetic output and as especially evident in his poetry of the 1930s, the period in which he forged a unique modernist poetic which rejected the referential, discursive and often propagandist voice of his contemporaries for a relish of exuberant word-play and language itself. Thomas took his major theme as the unity of all life in which the turmoil of sexuality and death linked the generations, envisaging men and women locked in cycles of growth, love, procreation, new growth, death, and new life. Thomas derived his imagery from sources which include the new scientific accounts of physiology and sexuality, the Bible, Welsh folklore, and Sigmund Freud as well as from the established literary canon. Whereas earlier appraisals of his work have found an impasse in its obscurity more recent accounts have given readings which have explored in depth the complexity of Thomas's allusions, accepting that obscurity, paradox and ambiguity are integral to his work. As Thomas wrote in a letter to Glyn Jones: "My own obscurity is quite an unfashionable one, based, as it is, on a preconceived symbolism derived (I'm afraid all this sounds wooly and pretentious) from the cosmic significance of the human anatomy".
=== Acting === Director Lal Jose noticed Kallingal on a magazine cover and approached her for a goat herder role in the Tamil film Mazhai Varappoguthu. The project did not go ahead, but director Shyamaprasad subsequently cast her in the lead female role of Varsha in Ritu (2009), which marked her acting debut. In 2009 she also appeared in the anthology film Kerala Cafe, in the segment Mrityunjayam, and in Neelathaamara directed by Lal Jose. In 2012, Kallingal was cast opposite Fahadh Faasil in 22 Female Kottayam, directed by Aashiq Abu, playing a nurse and rape survivor seeking justice. The film performed well commercially and won Kallingal the Kerala State Film Award for Best Actress and the Filmfare Award for Best Actress – Malayalam. The film also drew praise from critics; Sify wrote that Kallingal "poured her heart into her character" and delivered "a spectacular performance". In 2013, she hosted the Mazhavil Manorama reality show Midukki, following which the Kerala Film Chamber imposed a temporary ban on her for disregarding a recent notice by the chamber; the ban was subsequently revoked. That same year she played a housewife in August Club. Paresh C. Palicha of Rediff.com noted that Kallingal portrayed a character "who has learnt to stifle her feelings and finding other ways to give them an outlet". In 2015, she appeared alongside Manju Warrier in Rani Padmini, playing a disruptive North Indian woman on a road trip from Kerala to Shimla. The film was a commercial success and critic Deepa Soman described her performance as a "knockout".
== Synthesis == The preparation of acifluorfen first described in the Rohm & Haas patent includes as its final steps an Ullmann condensation between 2-chloro-4-trifluoromethylphenol and 2-nitro-5-fluorobenzonitrile. The intermediate is then hydrolysed using hydrobromic acid in acetic acid as solvent.
== Occurrence == The hydroxy group is pervasive in chemistry and biochemistry. Many inorganic compounds contain hydroxyl groups, including sulfuric acid, the chemical compound produced on the largest scale industrially. Hydroxy groups participate in the dehydration reactions that link simple biological molecules into long chains. The joining of a fatty acid to glycerol to form a triacylglycerol removes the −OH from the carboxy end of the fatty acid. The joining of two aldehyde sugars to form a disaccharide removes the −OH from the carboxy group at the aldehyde end of one sugar. The creation of a peptide bond to link two amino acids to make a protein removes the −OH from the carboxy group of one amino acid.
Sources: en.wikipedia.org
Protein–protein interaction prediction is a field combining bioinformatics and structural biology in an attempt to identify and catalog physical interactions between pairs or groups of proteins. Understanding protein–protein interactions is important for the investigation of intracellular signaling pathways, modelling of protein complex structures and for gaining insights into various biochemical processes. Experimentally, physical interactions between pairs of proteins can be inferred from a variety of techniques, including yeast two-hybrid systems, protein-fragment complementation assays (PCA), affinity purification/mass spectrometry, protein microarrays, fluorescence resonance energy transfer (FRET), and Microscale Thermophoresis (MST). Efforts to experimentally determine the interactome of numerous species are ongoing. Experimentally determined interactions usually provide the basis for computational methods to predict interactions, e.g. using homologous protein sequences across species. However, there are also methods that predict interactions de novo, without prior knowledge of existing interactions.
=== Effect of parental age and temperature === Offspring produced by older beetles have shorter larval stages than those produced by younger beetles. Larvae from the older beetles also show a rapid weight increase at an earlier age than those from young parents. At 25 °C, the larval stage was shortened, the number of larval molts decreased, and the durations of adult life decreased when parental age increased, compared to the beetles at 30 °C. Another study found that at 20°, 25°, and 30 °C, parental age does not have any effect on the duration of the egg stage, or the weights of the eggs. However, the amount of hatched eggs decreased when parental age increased. When eggs were laid during the first two months after emergence, approximately 90% of the eggs hatched. When they were laid after four months, only about 50% hatched. It was found that larvae from young parents grow at a slower rate, compared to larvae produced by the same parents, nine weeks earlier. At 30 °C, there were no other effects of parental age on the larvae. At 20° and 25 °C, the larvae from young parents required significantly more time to complete development, and had more molts compared to the larvae from the same parents after they had aged one more or longer. The duration of adult life decreased when parental age increased.
In addition to the classical nuclear AR, bicalutamide has been assessed at the membrane androgen receptors (mARs) and found to act as a potent antagonist of ZIP9 (IC50 = 66.3 nM), whereas it does not appear to interact with GPRC6A. The affinity of bicalutamide for the AR is relatively low as it is approximately 30 to 100 times lower than that of DHT, which is 2.5- to 10-fold as potent as an AR agonist as testosterone in bioassays and is the main endogenous ligand of the receptor in the prostate gland. However, typical clinical dosages of bicalutamide result in circulating levels of the drug that are thousands of times higher than those of testosterone and DHT, allowing it to powerfully prevent them from binding to and activating the receptor. This is especially true in the case of surgical or medical castration, in which testosterone levels in the circulation are approximately 95% reduced and DHT levels in the prostate gland are about 50 to 60% reduced. In women, levels of testosterone are substantially lower (20- to 40-fold) than in men, so much smaller doses of bicalutamide (e.g., 25 mg/day in the hirsutism studies) are necessary. Blockade of the AR by bicalutamide in the pituitary gland and hypothalamus results in prevention of the negative feedback of androgens on the hypothalamic–pituitary–gonadal axis (HPG axis) in males and consequent disinhibition of pituitary luteinizing hormone (LH) secretion. This, in turn, results in an increase in circulating LH levels and activation of the gonadal production of testosterone and by extension production of estradiol.
Sources: en.wikipedia.org
No. Cardarine is GW501516, a PPARδ agonist, while SARMs act on androgen receptors. The two classes are often grouped in informal discussions despite different mechanisms.
No. It has no approved medical indication in any country. Regulatory agencies have not cleared it for treatment or prevention of any condition.
Early clinical work stopped after rodent carcinogenicity findings. Those animal results raised concerns about long-term human risk, although direct human evidence is lacking. The human relevance of the tumors remains an open scientific question.
LC-MS/MS is common, often after sample cleanup. The assay targets GW501516 or its metabolites.