reference standard is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-03-28. Numbers and descriptions here follow the published literature rather than marketing material.
Identity and purity of SR9009 samples are usually checked with chromatographic and spectrometric methods. High-performance liquid chromatography can separate the compound from related impurities, while mass spectrometry provides molecular mass confirmation. Nuclear magnetic resonance spectroscopy may be used for structural verification in research settings. No single method proves biological activity, and certificates of analysis should be reviewed alongside raw data. Independent testing is often needed because online products vary widely.
SR9009 stability depends on temperature, moisture, light, and solvent. Solid material is generally kept cool and dry, while solutions may require protection from repeated warming and cooling. Degradation can appear as color changes, precipitate, or new chromatographic peaks. Researchers should follow supplier instructions and their own stability data. Long-term storage conditions for human use have not been established because the compound lacks approved clinical formulation.
SR9009 is supplied as a solid research chemical, often in milligram quantities. Laboratories typically weigh it in a controlled environment because fine powders can disperse. Stock solutions are commonly prepared in dimethyl sulfoxide and stored in small aliquots to reduce freeze-thaw cycles. Personal protective equipment and chemical fume hoods are standard when handling unknown or potent compounds. These practices address laboratory safety rather than human use.
Because REV-ERB receptors are core clock components, SR9009 has been examined for effects on daily rhythms as well as metabolism. Research has explored whether the compound can shift or reinforce circadian gene expression in tissues such as liver and muscle. Some studies report improved metabolic markers in obese or diabetic mice, while others show context-dependent responses. Questions remain about which effects are direct, which are secondary to timing, and how they might differ across species.
SR9009 is a synthetic small molecule studied as an agonist of REV-ERB nuclear receptors. REV-ERB alpha and REV-ERB beta help regulate circadian rhythms and metabolic gene expression. In laboratory research, SR9009 has been used to probe how these receptors affect skeletal muscle, liver, and adipose tissue. The compound was identified in academic drug-discovery work and is often described in scientific literature by its chemical name and research code. It is not an approved medicine, and human clinical data remain limited or absent.
SR9009 binds REV-ERB receptors and alters their repressive activity on target genes. This action can change transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. In rodent studies, treated animals have shown changes in muscle oxidative capacity and exercise performance, though effects vary by dose, duration, and model. The precise molecular steps connecting receptor binding to whole-body outcomes are still an active area of investigation. Findings in animals do not automatically translate to humans.
| Property | Value | Notes |
|---|---|---|
| Synonyms | SR9009; Stenabolic | Stenabolic is an informal name |
| Common form | Crystalline powder | Supplied in milligram to gram quantities |
| Long-term storage | -20 °C, desiccated, protected from light | Reduces degradation |
| Detection technique | LC-MS/MS | Common in anti-doping and research analysis |
| Regulatory status | Prohibited in sport by WADA | Not approved for human therapeutic use |
For long-term storage, SR9009 is typically kept as a solid at low temperature, protected from moisture and light. Desiccated conditions limit hydrolysis, while opaque containers reduce photochemical breakdown. Solutions are less stable than solids and are often stored frozen in aliquots to avoid repeated freeze-thaw cycles. Stability data are not standardized across all suppliers, so users should rely on certificate-of-analysis information when available. Degradation may appear as color change, precipitate, or decreased chromatographic purity.
Laboratory identification of SR9009 typically relies on chromatographic separation coupled to mass spectrometry, often with ultraviolet detection as a secondary check. Nuclear magnetic resonance spectroscopy can confirm molecular structure when a reference standard is available. Because many suppliers sell the compound as a research chemical, independent identity testing is important for experimental reproducibility. A single retention time is not sufficient proof of identity, especially when related compounds may be present. Purity assessments usually report a percentage based on area normalization.
REV-ERB proteins help regulate daily cycles in gene expression, including genes tied to lipid and glucose metabolism. SR9009 binds these receptors and alters their activity in cell and animal experiments. Consequences observed in rodents include changes in skeletal muscle oxidative capacity, blood lipid levels, and exercise performance. The precise chain from receptor occupancy to whole-body effects is still an active area of study. Human responses cannot be assumed from rodent data.
Most published work on SR9009 consists of preclinical studies. It is widely sold as a research chemical, a category that does not imply safety, efficacy, or pharmaceutical-grade quality. Sports anti-doping organizations have listed SR9009 as a prohibited substance, and its presence in an athlete sample can lead to sanctions. Legal status differs by country; in several jurisdictions it is not approved for human consumption and may be treated as an unapproved new drug.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is not a steroid, peptide, or natural hormone. In scientific literature, it appears under the code SR9009 and in non-scientific contexts as Stenabolic. The compound was identified through chemical screening efforts aimed at targeting circadian clock components. Its status remains investigational, and no regulatory agency has approved it as a human medicine.
Analytical identification of SR9009 typically relies on liquid chromatography coupled with tandem mass spectrometry. In biological samples, researchers first separate the compound from matrix components using protein precipitation, liquid-liquid extraction, or solid-phase extraction. High-performance liquid chromatography with ultraviolet detection and nuclear magnetic resonance spectroscopy can support structural confirmation of reference materials. Because SR9009 is a small, relatively lipophilic molecule, reverse-phase columns and acidic mobile phases are common. Laboratories often include isotope-labeled internal standards to improve quantification and to correct for ion suppression.
Stability depends on physical form, temperature, light exposure, and solvent. Solid SR9009 is generally stored cold and dry, with protection from light to limit degradation. Dimethyl sulfoxide stocks are common for laboratory work, but repeated freeze-thaw cycles can reduce compound integrity. Aqueous solutions may be less stable than organic stocks, and the ethyl ester in the structure can be susceptible to hydrolysis under certain conditions. Researchers typically validate storage conditions and recheck purity before quantitative experiments, especially when using archived material.
=== Imaging === According to guidelines from the American Heart Association and American Stroke Association Stroke Council, patients with TIA should have head imaging "within 24 hours of symptom onset, preferably with magnetic resonance imaging, including diffusion sequences". MRI is a better imaging modality for TIA than computed tomography (CT), as it is better able to pick up both new and old ischemic lesions than CT. CT, however, is more widely available and can be used particularly to rule out intracranial hemorrhage. Diffusion sequences can help further localize the area of ischemia and can serve as prognostic indicators. Presence of ischemic lesions on diffusion weighted imaging has been correlated with a higher risk of stroke after a TIA. Vessels in the head and neck may also be evaluated to look for atherosclerotic lesions that may benefit from interventions, such as carotid endarterectomy. The vasculature can be evaluated through the following imaging modalities: magnetic resonance angiography (MRA), CT angiography (CTA), and carotid ultrasonography/transcranial doppler ultrasonography. Carotid ultrasonography is often used to screen for carotid artery stenosis, as it is more readily available, is noninvasive, and does not expose the person being evaluated to radiation. However, all of the above imaging methods have variable sensitivities and specificities, making it important to supplement one of the imaging methods with another to help confirm the diagnosis (for example: screen for the disease with ultrasonography, and confirm with CTA).
==== Post mortem interval ==== Post mortem interval (PMI) is the time between death and discovery of a corpse. Calliphora vomitoria is important for PMI estimations because it is among the first species to lay eggs on the corpse. There are two ways of estimating PMI. One is killing the larvae, and then comparing the larvae's length and temperature to those in the standardized data. Another way to calculate PMI is to calculate the accumulated degree hours/days (ADH/D) that a larva needs to reach a certain developmental stage. The later method is the more widely accepted way to estimate PMI.
The basis of Dr. Quimby's theory is that there is no intelligence, no power or action in matter of itself, that the spiritual world to which our eyes are closed by ignorance or unbelief is the real world, that in it lie all the causes for every effect visible in the natural world, and that if this spiritual life can be revealed to us, in other words if we can understand ourselves, we shall then have our happiness or misery in our own hands ..." By 1856, Quimby had 500 patients a year. He would sit next to them and explain that the disease was something their minds could control; sometimes he would wet his hands and rub their heads, but it was the talking that helped them, he said, not the manipulation. Quimby began to write his thoughts down around 1859—his work was published posthumously as The Quimby Manuscripts in 1921—and was generous in allowing his patients to copy one of his essays, "Questions and Answers." This became an issue, from 1883 onwards, when Eddy was accused of having based Christian Science on his work.
Genetic gingival enlargement presents in children with firm, fibrotic, generalized gingival overgrowth beginning around tooth eruption, often requiring surgical management. These cases are identified by tissue overgrowth-related pseudopocket formation and generally intact periodontal attachment.
==== Resistance exercise and muscle atrophy ==== Resistance exercise is exercising a muscle or muscle group against external resistance (see strength training). Studies have found that: a) mice feeding on a high fat or normal diet and given the resistance exercise of repeatedly climbing up a 1 meter ladder for 40 minutes had higher levels of α-ketoglutarate in their blood and seven muscles than non-exercising mice feeding respectively on the high fat or normal diet; b) mice conducting ladder climbing for several weeks and eating a high fat diet developed lower fat tissue masses and higher lean tissue masses than non-exercising mice on this diet; c) mice not in exercise training fed α-ketoglutarate likewise developed lower fat tissue and higher lean tissue masses than α-ketoglutarate-unfed, non-exercising mice; d) OXGR1 was strongly expressed in the mouse adrenal gland inner medullas and either resistance training or oral α-ketoglutarate increased this tissue's levels of the mRNA that is responsible for the synthesis of OXGR1; e) α-ketoglutarate stimulated chromaffin cells isolated from mouse adrenal glands to release epinephrine but reduction of these cells' OXGR1 levels by small interfering RNA reduced this response; f) α-ketoglutarate increased the blood serum levels of epinephrine in mice expressing OXGR1 but not in Oxgr1 gene knockout mice (i.e., mice lacking the OXGR1 gene and protein); g) mice on the high fat diet challenged with α-ketoglutarate increased their blood serum levels of epinephrine and developed lower fat tissue masses and higher lean tissue masses but neither OXGR1 gene knockout mice nor mice that had only their adrenal glands' OXGR1 gene knocked out showed these responses; and h) OXGR1 gene knockout mice fed the high fat diet developed muscle protein degradation, muscle atrophy (i.e., wasting), and falls in body weight whereas control mice did not show these fat diet-induced changes. These findings indicate that in mice resistance exercise increases muscle production as well as serum levels of α-ketoglutarate which in turn suppresses diet-induced obesity (i.e., low body fat and high lean body masses) at least in part by stimulating the OXGR1 on adrenal gland chromaffin cells to release epinephrine. Additional mechanisms include inhibition of hepatic gluconeogenesis via serpina1e signaling (reducing hyperglycemia) and activation of the PHD3/ADRB2 pathway in muscle cells. Supplementation studies have shown that oral α-ketoglutarate increases serum levels of α-ketoglutarate, suppresses obesity and improves glucose tolerance in mice. See § Glucose tolerance below.
Sources: en.wikipedia.org
==== 2700–2799 ==== Social Security (Introduction of Disability Living Allowance) (Amendment) (No. 3) Regulations 1993 (S.I. 1993/2704) Capital Allowances (Corresponding Northern Ireland Grants) Order 1993 (S.I. 1993/2705) Building Societies (Designation of Qualifying Bodies) (No. 3) Order 1993 (S.I. 1993/2706) Education (No. 2) Act 1986 (Amendment) Order 1993 (S.I. 1993/2709) Housing Renovation etc. Grants (Grant Limit) (Amendment) Order 1993 (S.I. 1993/2711) Reconstitution of the River Ouzel Internal Drainage Board Order 1993 (S.I. 1993/2712) Placing on the Market and Supervision of Transfers of Explosives Regulations 1993 (S.I. 1993/2714) Food Labelling (Scotland) Amendment Regulations 1993 (S.I. 1993/2731) Teachers (Education, Training and Recommendation for Registration) (Scotland) Regulations 1993 (S.I. 1993/2732) Portsmouth Mile End Quay (Berth No. 2 Extension) Harbour Revision Order 1993 (S.I. 1993/2733) Criminal Justice Act 1993 (Commencement No. 3) Order 1993 (S.I. 1993/2734) Social Security (Contributions) (Miscellaneous Amendments) Regulations 1993 (S.I. 1993/2736) Public Service Vehicles (Registration of Local Services) (Amendment) Regulations 1993 (S.I. 1993/2752) Public Service Vehicles (Operators' Licences) (Amendment) Regulations 1993 (S.I. 1993/2753) Public Service Vehicles (Traffic Commissioners: Publication and Inquiries) (Amendment) Regulations 1993 (S.I. 1993/2754) Copyright (Certification of Licensing Scheme for Educational Recording of Broadcasts) (Open University Educational Enterprises Limited) Order 1993 (S.I.
In many-body potentials, the potential energy includes the effects of three or more particles interacting with each other. In simulations with pairwise potentials, global interactions in the system also exist, but they occur only through pairwise terms. In many-body potentials, the potential energy cannot be found by a sum over pairs of atoms, as these interactions are calculated explicitly as a combination of higher-order terms. In the statistical view, the dependency between the variables cannot in general be expressed using only pairwise products of the degrees of freedom. For example, the Tersoff potential, which was originally used to simulate carbon, silicon, and germanium, and has since been used for a wide range of other materials, involves a sum over groups of three atoms, with the angles between the atoms being an important factor in the potential. Other examples are the embedded-atom method (EAM), the EDIP, and the Tight-Binding Second Moment Approximation (TBSMA) potentials, where the electron density of states in the region of an atom is calculated from a sum of contributions from surrounding atoms, and the potential energy contribution is then a function of this sum.
== Annual events == Fellows in American Letters of the Library of Congress Gershwin Prize for Popular Song Library of Congress Prize for American Fiction Founder's Day Celebration Mostly Lost Film Identification Workshop National Book Festival
If the person presents more than eight hours after the paracetamol overdose, then activated charcoal is not useful, and acetylcysteine is started immediately. In earlier presentations, charcoal can be given when the patient arrives and acetylcysteine is initiated while waiting for the paracetamol level results to return from the laboratory. In United States practice, intravenous (IV) and oral administration are considered to be equally effective and safe if given within 8 hours of ingestion. However, IV is the only recommended route in Australasian and British practice. Oral acetylcysteine is given as a 140 mg/kg loading dose followed by 70 mg/kg every four hours for 17 more doses, and if the patient vomits within 1 hour of dose, the dose must be repeated. Oral acetylcysteine may be poorly tolerated due to its unpleasant taste, odor, and its tendency to cause nausea and vomiting. If repeated doses of charcoal are indicated because of another ingested drug, then subsequent doses of charcoal and acetylcysteine should be staggered. Intravenous acetylcysteine is given as a continuous infusion over 20 hours for a total dose 300 mg/kg. Recommended administration involves infusion of a 150 mg/kg loading dose over 15 to 60 minutes, followed by a 50 mg/kg infusion over four hours; the last 100 mg/kg are infused over the remaining 16 hours of the protocol.
Argiopine: contains 2,4-dihydroxyphenylacetic acid. It is also named Arg-636. Argiopinines: (4-hydroxyindol-3-yl) acetic acid is carried as the chromophore. These molecules are: Arg-630, Arg-658, Arg-659, Arg-744, Arg-759. Pseudoargiopinines: They contain a (indol-3-yl) acetic acid. This group is composed of: Arg-373, Arg-728, Arg-743.
Sources: en.wikipedia.org
Laboratories commonly use liquid chromatography coupled with mass spectrometry to detect SR9009. The method can identify the compound and estimate concentration in a sample. Detection limits depend on the matrix and instrument.
Research-grade purity indicates a supplier's measured percentage of the intended compound. It does not guarantee safety, sterility, or suitability for human consumption. Buyers should request a certificate of analysis with chromatograms and test methods.
Sports regulators prohibit SR9009 because it is a non-approved substance with potential performance-altering effects. Its presence can be detected in anti-doping testing. Athletes are responsible for substances found in their samples.
SR9009 is a synthetic research compound that acts on REV-ERB nuclear receptors. It is not approved for human use and is sold only as a research chemical. Its effects have been studied mainly in cells and rodents.