GW501516 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 2026-05-05 and is reviewed periodically as new material appears.
Laboratory detection of cardarine typically involves sample preparation followed by chromatographic separation and mass spectrometric identification. Urine is the most common matrix for anti-doping tests, though blood and hair have also been explored. Methods can target the parent compound or its metabolites, depending on the expected window of detection. Reference standards are required for accurate quantification. Matrix effects and dilution can influence results, so laboratories use internal standards and validation protocols. The exact detection window varies with dose, route, and individual metabolism.
A common misconception is that cardarine has been proven safe for human use. In reality, human clinical data are limited, and long-term animal studies have raised concerns about cancer. Another misconception is that it is a supplement or vitamin-like compound. It is a synthetic research chemical with no approved medical indication. Scientific discussion often focuses on its mechanism and detection rather than therapeutic use. Regulatory and anti-doping literature treats it primarily as a prohibited substance.
Cardarine is a common name for GW501516, also GW-1516, a synthetic compound developed as a peroxisome proliferator-activated receptor delta (PPARδ) agonist. It belongs to a class of agents that modulate gene transcription related to lipid and energy metabolism. The compound was studied in preclinical and early clinical research for metabolic and cardiovascular conditions, but it did not progress to approved therapeutic use. Its name appears in fitness and sports contexts despite not being approved as a drug.
PPARδ is a nuclear receptor that influences transcription of genes involved in fatty acid oxidation, lipid transport, and energy homeostasis. GW501516 binds and activates this receptor with high selectivity relative to PPARα and PPARγ in laboratory assays. Activation alters expression of target genes in skeletal muscle, liver, and adipose tissue in animal models. The exact clinical consequences of these changes in humans remain incompletely characterized, and observed effects in animals do not establish therapeutic benefit or safety.
Published studies have examined GW501516 in animal models of obesity, insulin resistance, and exercise endurance. Early human trials reportedly ended, and development was discontinued after preclinical findings raised concerns about cancer in some rodent studies. Regulatory agencies have not approved cardarine for any medical use. Its availability through non-pharmaceutical channels raises questions about identity, purity, and legal status that are separate from its laboratory pharmacology. Those questions are often addressed through analytical testing rather than assumptions about product labels.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport | Listed by WADA as a PPARδ agonist. |
| Typical detection matrix | Urine | Most common sample for anti-doping analysis. |
| Common analytical method | LC-MS/MS | Liquid chromatography-tandem mass spectrometry. |
| Common synonyms | GW501516, GSK-516, endurobol | Names found in research and fitness contexts. |
| Typical detection window | Variable | Depends on dose, route, and individual metabolism. |
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.
Quality assessment for cardarine samples usually combines identity, purity, and impurity testing. Nuclear magnetic resonance spectroscopy and mass spectrometry can confirm molecular structure, while high-performance liquid chromatography estimates purity. Certificates of analysis from testing laboratories may list these results, but they do not establish safety or legality. In the absence of approved manufacturing, products sold online may contain the wrong compound, variable amounts, or unlisted contaminants. Independent verification is therefore central to analytical work and to interpreting any reported biological activity.
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.
Legal status varies by country. In some places, cardarine is controlled under medicines or psychoactive substances laws; in others, it may be sold with minimal oversight as a research chemical. Customs agencies have intercepted shipments, and several national health agencies have issued warnings about products marketed for bodybuilding or performance enhancement. The lack of a standardized pharmaceutical supply means identity, purity, and contamination levels can differ widely between samples. These factors make cardarine a regulatory and public health concern rather than a conventional prescription drug.
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.
A biopharmaceutical, also known as a biological medical product, or biologic, is any pharmaceutical drug product manufactured in, extracted from, or semisynthesized from biological sources. Different from totally synthesized pharmaceuticals, they include vaccines, whole blood, blood components, allergenics, somatic cells, gene therapies, tissues, recombinant therapeutic protein, monoclonal antibodies, and living medicines used in cell therapy. Biopharmaceuticals can be composed of sugars, proteins, nucleic acids, or complex combinations of these substances, or may be living cells or tissues. They (or their precursors or components) are isolated from living sources—human, animal, plant, fungal, or microbial. They can be used in both human and animal medicine. Terminology surrounding biopharmaceuticals varies between groups and entities, with different terms referring to different subsets of therapeutics within the general biopharmaceutical category. The term biologics is often used more restrictively to mean biopharmaceuticals that are produced using recombinant DNA technology. Some regulatory agencies use the terms biological medicinal products or therapeutic biological product to refer specifically to engineered macromolecular products like protein- and nucleic acid-based drugs, distinguishing them from products like blood, blood components, or vaccines, which are usually extracted directly from a biological source. Biopharmaceutics is pharmaceutics that works with biopharmaceuticals. Biopharmacology is the branch of pharmacology that studies biopharmaceuticals.
In countries with significant populations of individuals observing religions which place restrictions on material choices, vendors typically clarify the source of leather in their products. Such labeling helps facilitate religious observance, so that, for example, a Muslim will not accidentally purchase pigskin or a Hindu can avoid cattleskin. Such taboos increase the demand for religiously neutral leathers such as ostrich and deer. Jainism prohibits the use of leather, since it is obtained by killing animals, and Judaism forbids the comfort of wearing leather shoes on Yom Kippur, Tisha B'Av, and during mourning.
enzymes like beta-glucuronidase (pictured) export factors such as SecB from Escherichia coli magnesium ion transporters such as CorA. lectins such as Concanavalin A IMPDH and IMPDH2 Examples of heterotetramers include haemoglobin (pictured), the NMDA receptor, some aquaporins, some AMPA receptors, as well as some enzymes.
Sources: en.wikipedia.org
==== Salts ==== Lysis buffer usually contains one or more salts. The function of salts in lysis buffer is to establish an ionic strength in the buffer solution. Some of the most commonly used salts are NaCl, KCl, and (NH4)2SO4. They are usually used with a concentration between 50 and 150 mM.
== Uses == PPG is used in many polyurethane formulations. Synthesis of waterborne polymers has been a feature with this substance. As the basic building block is propylene oxide, there are 3 carbons per oxygen on the backbone. This confers some degree of water miscibility though not as good as ethylene oxide-based molecules. It is used to synthesize the epoxy reactive diluent and flexibilizer, Poly(propylene glycol) diglycidyl ether. Another use of PPG is as a surfactant, wetting agent and dispersant in leather finishing. PPG is also employed as a reference and calibrant in mass spectrometry and HPLC. PPG and derivatives may be used as defoamers in drilling and other applications. It is also used as a primary ingredient in the making of paintballs. It has been evaluated as a corrosion inhibitor.
== Thermodynamics == The thermodynamics of metal ion complex formation provides much significant information. In particular it is useful in distinguishing between enthalpic and entropic effects. Enthalpic effects depend on bond strengths and entropic effects have to do with changes in the order/disorder of the solution as a whole. The chelate effect, below, is best explained in terms of thermodynamics. An equilibrium constant is related to the standard Gibbs free energy change for the reaction
Birch bark tar use as an adhesive began in the Middle Paleolithic. Neanderthals produced tar through dry distillation of birch bark as early as 200,000 years ago. A 2019 study demonstrated that birch bark tar production can be a simpler, more discoverable process by directly burning birch bark under overhanging stone surfaces in open-air conditions. However, at Königsaue (Germany), Neanderthals did not make tar with this method but rather employed a technically more demanding underground production method. A find from the Dutch North Sea and two tools from the Italian site Campitello show that Neanderthals used birch bark tar as a backing on small 'domestic' stone tools. Birch bark tar also has been used as a disinfectant, in leather dressing, and in medicine. A piece of 5,000-year-old chewing gum made from birch bark tar, and still bearing tooth imprints, was found in Kierikki, Finland. Genetic material left in the gum enabled novel research to identify population movements, types of food consumed, and types of oral bacteria found on their teeth. A different chewing gum sample, dated to 5,700 years old, was found in southern Denmark. A complete human genome and oral microbiome was sequenced from chewed birch bark tar. Researchers identified that the individual who chewed the gum was a female who was closely related genetically to hunter-gatherers from mainland Europe. Fletching on arrows were fastened with birch bark tar, and rawhide lashing and birch bark tar were used to fix axe blades in the Mesolithic period.
Sources: en.wikipedia.org
Yes, WADA prohibits cardarine as a PPARδ agonist. It appears on the prohibited list and can be detected in urine or blood. Athletes using it risk sanctions.
Detection usually uses liquid chromatography-tandem mass spectrometry after sample cleanup. Laboratories look for the parent compound or metabolites. The method requires validated reference standards and controls.
Legality varies by country. In many places it is an unapproved drug and cannot be legally sold for human consumption. Purchasing from online vendors carries legal and quality risks.
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.