If you have been reading about Certificate of analysis 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.
Last reviewed on 2025-10-18. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| 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 |
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.
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.
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.
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.
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.
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.
Profilin binds to monomeric actin thereby occupying an actin-actin contact site; in effect, profilin sequesters actin from the pool of polymerizable actin monomers. However, profilin also catalyzes the exchange of actin-bound ADP to ATP thereby converting poorly polymerizing ADP-actin monomers into readily polymerizing ATP-actin monomers. On top of that, profilin has a higher affinity for ATP- than for ADP-actin monomers. Thus in a mixture of actin, profilin, and nucleotides (ADP and ATP), actin will polymerize to a certain extent, which may be estimated by the law of mass action. Profilin-actin complexes are fed into growing actin polymers by proteins such as formin, Wiskott-Aldrich syndrome protein and Vasodilator-stimulated phosphoprotein which contain proline-rich FH1-domains. This mode of stimulated actin polymerization is much faster than unaided polymerization. Profilin is essential for this mode of polymerization because it recruits the actin monomers to the proline-rich proteins. Profilin binds some variants of membrane phospholipids (phosphatidylinositol (4,5)-bisphosphate and inositol trisphosphate). The function of this interaction is the sequestration of profilin in an "inactive" form, from where it can be released by action of the enzyme phospholipase C. Profilin negatively regulates PI(3,4)P2 limiting recruitment of lamellipodia to the leading edge of the cell. Profilin is one of the most abundant actin monomer binders, but proteins such as CAP and (in mammals) thymosin β4 have some functional overlaps with profilin.
==== Molecular interactions ==== As MALS can provide molar mass and size of molecules, it permits study into protein-protein binding, oligomerization and the kinetics of self-assembly, association and dissociation. By comparing the molar mass of a sample to its concentration, one can determine the binding affinity and stoichiometry of interacting molecules.
== Structure == Peptide YY is related to the pancreatic peptide family by having 18 of its 36 amino acids located in the same positions as pancreatic peptide. The two major forms of peptide YY are PYY1-36 and PYY3-36, which have PP fold structural motifs. However, the most common form of circulating PYY immunoreactivity is PYY3-36, which binds to the Y2 receptor (Y2R) of the Y family of receptors. Peptide YY3-36 (PYY) is a linear polypeptide consisting of 36 amino acids with structural homology to NPY and pancreatic polypeptide. The PP-fold motif is found throughout this family and relates to the 3D structure. The PP-fold is formed through the incorporation of certain residues which are predominately Pro2, Pro5, Pro8, Gly9, Tyr20 and Tyr27. This PP-fold has been found to protect the peptide against enzymatic attack as well as producing a hydrophobic pocket which is inherently overall energy reducing. In addition to containing the PP-fold motif, PYY and its derivative PYY3- 36 also have a high C-terminal α-helix proportion, suggested to be extremely important for the structural integrity of PYY.
She collaborated with the company again in February 2025, to promote the "Cherry Crush Zero Sugar" flavour, in which she and Jedward attempted a Guinness World Record to see how many post-it notes they could attach to her within a minute. The attempt, which was overseen by an adjudicator, saw them attach 30, failing to break the record of 70.
18 hours) in CYP2D6 poor metabolizers versus CYP2D6 extensive metabolizers. Circulating 4-hydroxyatomoxetine levels are about 1% of those of circulating atomoxetine levels in CYP2D6 extensive metabolizers and about 0.1% of those of circulating atomoxetine levels in CYP2D6 poor metabolizers. Similarly, N-desmethylatomoxetine circulates at much lower levels than atomoxetine, about 5% of those of atomoxetine in CYP2D6 extensive metabolizers and 45% of those of atomoxetine in CYP2D6 poor metabolizers. 4-Hydroxyatomoxetine shows similar affinity for the norepinephrine transporter (NET) as atomoxetine but much higher affinity for the serotonin transporter (SERT) in comparison (with SERT affinity ~14-fold lower than NET affinity), whereas N-desmethylatomoxetine shows much lower affinity for the monoamine transporters (MATs) than atomoxetine and 4-hydroxyatomoxetine (with NET affinity ~20-fold lower than that of atomoxetine). Despite differences in atomoxetine metabolism, CYP2D6 status has been said in literature reviews to not affect the overall tolerability and safety of atomoxetine. However, poor metabolizers did show greater heart rate increase (+9.4–11 bpm vs. +5.0–7.5 bpm), blood pressure increase (4.21 mm Hg vs. 2.13 mm Hg systolic and 2.75 mg Hg vs. 2.40 mm Hg diastolic), and more weight loss (–1.2 kg vs. +0.8 mg) than extensive metabolizers.
Sources: en.wikipedia.org
=== Resistance === Bacteria that show no clinically relevant response to ertapenem include methicillin-resistant Staphylococcus species (including MRSA) as well as Acinetobacter, Aeromonas, Enterococcus, and Pseudomonas. Microorganisms can become resistant to ertapenem by producing carbapenemases, enzymes that inactivate the drug by opening the beta-lactam ring. Other mechanisms of resistance against carbapenems are development of efflux pumps that transport the antibiotics out of the bacterial cells, mutations of PBPs, and mutations of Gram-negative bacteria's porins which are necessary for carbapenems to enter the bacteria.
Sucre wanted to delay any union of Bolivia with Peru as long as possible (knowing that it would fall under the latter's hegemony when it passed, weakening his government), annex all the territories offered by Ortiz, confront Colombia with Peru, secure his back by agreeing with Chile and Buenos Aires, and separate Arequipa, Cuzco and Puno from Peru. All this is demonstrated when Sucre indicated to Ortiz de Zevallos that: "only under that plan could Bolivia not fear that Peru would absorb it, as happens when a small State links up with a larger and stronger one". As well as when in 1827, Sucre appointed dean Gregorio Funes, a Bolivarian Argentine, who was carrying out the functions of Colombian minister in Buenos Aires, to receive the post of Bolivian minister in the same Argentine capital. Through Funes, Sucre addressed the issue of an alliance between Bolivia, Argentina and Chile, which was supposedly to stop Brazilian expansionism, but in practice he was looking for support against Peru because he knew its weakness against it, and suggested that the participation of Gran Colombia in the war against Brazil could occur through a treaty. From Santiago de Chile, Andrés Santa Cruz interpreted Sucre's opening to Buenos Aires as an attempt to form "an anti-popular and very particularly anti-Peruvian pact." The negotiations did not prosper because the Peruvians also sent agents who assured that Bolívar intended to divide the continent between two great empires: one Colombian and the other Brazilian.
=== Analysis of E. coli bacteria in water sources === A quick test for fecal contamination of water sources or soil is a check for the presence of E. coli bacteria performed with the help of MacConkey agar plates or Petri dishes. E. coli bacteria uniquely develop red colonies at temperature of approximately 43 °C (109 °F) overnight. Although most strains of E. coli are harmless, their presence is indicative of fecal contamination, and hence an increased possibility of the presence of more dangerous organisms. Fecal contamination of water sources is highly prevalent worldwide, accounting for the majority of unsafe drinking water. In developing countries most sewage is discharged without treatment. Even in developed countries events of sanitary sewer overflow are not uncommon and regularly pollute the Seine River (France) and the River Thames (England), for example.
Other forms are due to different diseases causing overabundant or abnormal protein production – such as with overproduction of immunoglobulin light chains (termed AL amyloidosis), or with continuous overproduction of acute phase proteins in chronic inflammation (which can lead to AA amyloidosis). About 60 amyloid proteins have been identified so far. Of those, at least 36 have been associated with a human disease. All amyloid fibril proteins start with the letter "A" followed by the protein suffix (and any applicable specification). See below for a list of amyloid fibril proteins which have been found in humans:
Proteins are primarily classified by sequence and structure, although other classifications are commonly used. Especially for enzymes the EC number system provides a functional classification scheme. Similarly, gene ontology classifies both genes and proteins by their biological and biochemical function, and by their intracellular location. Sequence similarity is used to classify proteins both in terms of evolutionary and functional similarity. This may use either whole proteins or protein domains, especially in multi-domain proteins. Protein domains allow protein classification by a combination of sequence, structure and function, and they can be combined in many ways. In an early study of 170,000 proteins, about two-thirds were assigned at least one domain, with larger proteins containing more domains (e.g. proteins larger than 600 amino acids having an average of more than 5 domains).
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.
Anti-doping laboratories typically use LC-MS/MS to detect GW501516 and its metabolites in urine. The method is sensitive and can identify the compound at low concentrations. Detection depends on sample timing, metabolism, and the specific assay.