A practical reference on circadian rhythm: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-07-26 and is reviewed periodically as new material appears.
Detection in biological samples can be complicated by rapid metabolism and low circulating concentrations. Some studies report phase I and phase II metabolites, and analytical methods may need to target those species in addition to the parent compound. Immunoassays are not broadly available, so mass spectrometry remains the main confirmatory approach. For anti-doping testing, laboratories look for SR9009 and its metabolites using validated LC-MS methods. Open questions include how long metabolites remain detectable and how different routes of administration alter detection windows.
In laboratory settings, SR9009 is typically characterized by liquid chromatography–mass spectrometry (LC-MS) or high-performance liquid chromatography with ultraviolet detection (HPLC-UV). These methods can confirm identity and estimate purity, but they require reference standards for accurate quantification. Because SR9009 is not a licensed pharmaceutical, no harmonized pharmacopeial monograph exists. Laboratories often validate in-house methods for matrices such as plasma, urine, or cell culture media. Sample preparation may involve protein precipitation or liquid-liquid extraction before analysis.
Laboratory studies often administer SR9009 by injection because oral absorption appears poor in rodents. Reported pharmacokinetic properties include rapid metabolism and low systemic exposure after oral dosing. Human pharmacokinetic data are sparse, so absorption, distribution, metabolism, and excretion in people are not well defined. Some research explores related REV-ERB compounds with improved drug-like properties. Regulatory approval for any REV-ERB agonist as a human medicine has not been granted to date.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ, also called NR1D1 and NR1D2. These receptors help regulate circadian rhythms and metabolic gene programs. The compound was developed for laboratory research, not as an approved therapeutic. Its identity is distinct from steroid hormones and selective androgen receptor modulators. Scientific interest centers on how REV-ERB activation changes gene expression in cells and animal models.
| Property | Value | Notes |
|---|---|---|
| Appearance | Off-white to pale yellow solid | Visual description varies with purity and source |
| Solubility | Soluble in DMSO and ethanol; poorly soluble in water | Organic stock solutions are common in research |
| Typical storage | -20 °C, desiccated, protected from light | Avoid repeated freeze-thaw cycles |
| Typical analytical method | LC-MS or HPLC-UV | Reference standards are needed for quantification |
| Molar mass | Approximately 437.9 g/mol | Calculated from the reported free-base formula |
Regulatory agencies have not approved SR9009 for human therapeutic use. It is typically sold as a research chemical with labels stating that it is not for human consumption. The World Anti-Doping Agency prohibits the substance in sport, generally under the category of non-approved substances. Customs and national laws may restrict importation, sale, or possession. Product quality and legal status can vary by country and vendor, and therapeutic claims are not permitted in regulated advertising because the compound lacks approval.
Several misconceptions surround SR9009. It is often described as a SARM, a steroid, or an exercise pill, but its known target is the REV-ERB receptor family. Rodent studies have examined exercise capacity and metabolic markers, yet human outcomes remain unproven. Oral bioavailability appears low in animals, and human pharmacokinetics are not well characterized. Online products may contain impurities or different compounds, so identity and purity testing are important for research use.
Analytical chemists detect SR9009 with liquid chromatography-tandem mass spectrometry, commonly abbreviated LC-MS/MS. Sample preparation may involve protein precipitation, liquid-liquid extraction, or solid-phase extraction before analysis. Laboratories can target the parent compound or its metabolites, depending on the matrix and the purpose of testing. Anti-doping methods require sensitive and specific assays because concentrations in biological samples can be low. Reference standards and validated methods are essential for reliable identification and quantification.
Pharmacokinetic data for SR9009 are limited in published literature. Some reports indicate low oral bioavailability and rapid clearance in animals, which complicates interpretation of exposure and effect. Researchers often use injected routes in preclinical work to achieve measurable systemic levels. Analytical studies rely on mass spectrometry to detect the parent compound and its metabolites. Questions about tissue distribution, active metabolites, and long-term consequences remain open. Species differences in metabolism can affect observed half-life and target engagement.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. These receptors help regulate circadian rhythms and metabolic gene expression. In laboratory experiments, SR9009 binds these receptors and alters transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. It is not a naturally occurring compound and has no approved therapeutic use. Research interest stems from its ability to modify energy metabolism in cells and animal models.
Handling recommendations for SR9009 in a laboratory setting include storing the solid at low temperature, protected from light and moisture. The compound is often dissolved in dimethyl sulfoxide or ethanol for experiments. Solutions should be prepared with appropriate personal protective equipment and disposed of according to local rules. Stability data for long-term storage are limited, so stock solutions are typically kept cold and used within defined periods. Records of preparation date and concentration support reproducibility.
SR9009 is not approved as a medicine by major regulatory agencies. It is commonly sold as a research chemical, a category that may fall outside customary drug approval and quality rules. In sports, the World Anti-Doping Agency lists SR9009 as a prohibited substance. Athletes who use it can face sanctions if it is detected in a sample. Legal status varies by country, and importation may be restricted. Enforcement practices differ across borders.
Regulatory and sporting contexts treat SR9009 as a prohibited substance in many elite competitions. Its presence on banned lists reflects concerns about performance enhancement and unknown long-term safety. Analytical chemists have developed methods to detect the parent compound and its metabolites in urine and blood. Literature discussions distinguish between in vitro potency, animal pharmacology, and anecdotal human reports. The latter are difficult to verify because products sold online may lack purity or contain different compounds.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. These receptors help regulate circadian rhythms, lipid metabolism, and inflammatory gene expression. In cell and animal experiments, SR9009 alters transcription of clock-controlled genes and metabolic pathways. The compound is not a hormone and does not resemble classical steroid structures. Its activity depends on binding to the ligand-binding domain of REV-ERB, where it can modify corepressor recruitment.
Research interest in SR9009 grew from studies of circadian biology and metabolic disease. Preclinical reports describe effects on exercise capacity, muscle metabolism, and blood lipid levels in rodents, but these findings come from controlled laboratory settings. The compound has low oral bioavailability in animals, which limits systemic exposure after swallowing. Investigators often use injected routes in experiments to achieve measurable plasma concentrations. Human clinical data are sparse, no approved therapeutic product exists, and whether animal effects translate to humans remains an open question.
Bioinformatics (or "gold biotechnology") is an interdisciplinary field that addresses biological problems using computational techniques, and makes the rapid organization as well as analysis of biological data possible. The field may also be referred to as computational biology, and can be defined as, "conceptualizing biology in terms of molecules and then applying informatics techniques to understand and organize the information associated with these molecules, on a large scale". Bioinformatics plays a key role in various areas, such as functional genomics, structural genomics, and proteomics, and forms a key component in the biotechnology and pharmaceutical sector. Blue biotechnology is based on the exploitation of sea resources to create products and industrial applications. This branch of biotechnology is the most used for the industries of refining and combustion principally on the production of bio-oils with photosynthetic micro-algae. Green biotechnology is biotechnology applied to agricultural processes. An example would be the selection and domestication of plants via micropropagation. Another example is the designing of transgenic plants to grow under specific environments in the presence (or absence) of chemicals. One hope is that green biotechnology might produce more environmentally friendly solutions than traditional industrial agriculture. An example of this is the engineering of a plant to express a pesticide, thereby ending the need of external application of pesticides. An example of this would be Bt corn.
=== Red blood cell rejuvenation === Red blood cell rejuvenation is a method which aims to increase the levels of 2,3-diphosphoglycerate (2,3-DPG) and ATP in stored red blood cell concentrates, as the levels of both 2,3-DPG and ATP decrease over time. The rejuvenation process includes incubation of the red blood cells with a rejuvenation solution and subsequent washing. ATP is an important driver of a number of metabolic functions of the red blood cell, and declined ATP levels have been linked to reduced post-transfusion in vivo survival of the red blood cells. High levels of 2,3-DPG facilitates oxygen unloading from the red blood cells in the capillaries.
Benzoctamine is a drug that possesses sedative and anxiolytic properties. Marketed as Tacitin by Ciba-Geigy, it is different from most sedative drugs because in most clinical trials it does not produce respiratory depression, but actually stimulates the respiratory system. As a result, when compared to other sedative and anxiolytic drugs such as benzodiazepines like diazepam, it is a safer form of tranquilizing. However, when co-administered with other drugs that cause respiratory depression, like morphine, it can cause increased respiratory depression. Medically, benzoctamine is used as a treatment for anxious outpatients to control aggression, enuresis, fear, and minor social maladjustment in children. Its anxiolytic effects are most similar to diazepam, another anxiolytic, but unlike diazepam, benzoctamine has antagonistic effects on epinephrine and norepinephrine, and appears to increase serotonin levels. While little is understood about how it carries out its effects, studies point to reduced serotonin, epinephrine, and norepinephrine as partial causes of its pharmacologic and behavioral effects. Animal studies have shown sedative hypnotic drugs tend to show dependency in animals, but benzoctamine has been shown to not be addictive. Other animal studies also point to the drug as a possible mechanism by which to reduce blood pressure through the adrenergic system. Chemically, benzoctamine belongs to the class of compounds called dibenzobicyclo-octadienes.
Starting on 22 August 2009, he walked from Kennedy Airport in New York City to within 15 miles of Devil's Lake, North Dakota. This was a distance of 2,053 miles (3,304 km) and Skinner stopped his journey on 3 December 2009, after three days with windchills down to −30 Fahrenheit. During the trip Skinner had to make incisions in his feet to relieve the pressure from blisters, suffered food poisoning, met up with a wolf in Upper Michigan, had to face down two wild dogs, and had ski masks frozen to his beard in North Dakota. On the journey he appeared on television, radio and in newspaper articles. He also wrote a daily blog for the National Hospice Foundation. He met hospice patients, including one woman with a terminal illness, who said that at times she could forget she was ill, thanks to the care she received in a hospice house in Buffalo, New York. He also met a man with lung cancer who could not sleep in hospitals, where there was always someone coming to check on him. In the hospice house in Windsor, Ontario, the man had a peaceful room to himself, where he could finally get some rest.
•NO + O3 → •NO2 + O2 + hν The activated NO2[◊] luminesces broadband visible to infrared light as it reverts to a lower energy state. A photomultiplier and associated electronics count the photons that are proportional to the amount of nitric oxide (NO) present. To determine the amount of nitrogen dioxide, NO2, in a sample (containing no NO), it must first be converted to NO by passing the sample through a converter before the above ozone activation reaction is applied. The ozone reaction produces a photon count proportional to NO that is proportional to NO2 before it was converted to NO. In the case of a mixed sample that contains both NO and NO2, the above reaction yields the amount of NO and NO2 combined in the air sample, assuming that the sample is passed through the converter. If the mixed sample is not passed through the converter, the ozone reaction produces activated NO2[◊] only in proportion to the NO in the sample. The NO2 in the sample is not activated by the ozone reaction. Though unactivated NO2 is present with the activated NO2[◊], photons are emitted only by the activated species that is proportional to original NO. The final step is to subtract NO from (NO + NO2) to yield NO2
Sources: en.wikipedia.org
Consultant Urologist, South Tyneside and Sunderland NHS Foundation Trust. For services to the NHS. Dr. Benjamin Marc Ellis. For services to Healthcare, to Equality and to the Jewish Community. Audley Horace English. Co-Founder, Society of Black Architects. For services to Architecture and Sustainability. Professor Stephen James Weston Evans. Emeritus Professor of Pharmacoepidemiology, London School of Hygiene and Tropical Medicine. For services to the Safety of Medicines. Stephen Wynne Evans. Founder, Belief. For voluntary and charitable services in North Wales. Helen Adesuwa Imatitkua Fadipe. Founder and Chair, BAME Planners Network. For services to Town Planning. Paul Fairweather. Trustee, Breakthrough Ltd. For services to Disabled People and to the LGBT Community in the North West. Catherine Susan, Baroness Fall. Lately Non Executive Director, Cultural Recovery Board. For services to Culture. Rhiane Estelle Fatinikun. Founder, Black Girls Hike. For services to Nature and to Diversity. Julie Patricia Felix. For services to Dance Education. James St John Fenny. Head of Office, Public Defender Service and Transplant Surgery Ambassador. For services to Criminal Justice and to Organ Donor Awareness. Dr. Julia Helen Fentem. Executive Vice President, Safety, Environmental and Regulatory Science, Unilever. For services to Human Health and Animal Welfare. Jacqueline Ferguson. President, London College of Dance Network and Volunteer, Healthwatch (Kensington and Chelsea). For services to the community in London. Lucy Catherine Ferguson. Founder and Director, Mediorite.
== Litigation == CLIA itself has not been the subject of much litigation. Federal district courts have held that the CLIA did not create a private cause of action for individuals to sue laboratories that do not comply with its provisions.
C13H9−CH2−OC(O)NHR + (CH2)5NH → (CH2)5NH+2 + [C13H8−CH2−OC(O)NHR]− [C13H8−CH2−OC(O)NHR]− → C13H8=CH2 + −OC(O)NHR −OC(O)NHR + (CH2)5NH+2 → HOC(O)NHR + (CH2)5NH HOC(O)NHR → CO2 + RNH2 C13H8=CH2 + (CH2)5NH → C13H9−CH2N(CH2)5
In 2001, various tyrannosaurid teeth and a metatarsal unearthed in a quarry near Zhucheng, China, were assigned by Chinese paleontologist Hu Chengzhi to the newly erected species Tyrannosaurus zhuchengensis. However, in a nearby site, a right maxilla and left jawbone were assigned to the newly erected tyrannosaurid genus Zhuchengtyrannus in 2011. It is possible that T. zhuchengensis is synonymous with Zhuchengtyrannus. In any case, T. zhuchengensis is considered to be a nomen dubium as the holotype lacks diagnostic features below the level Tyrannosaurinae. In 2006, a fragmentary tyrannosaurid lacrimal (CM 9401) from the Judith River Formation of Fergus County, Montana, was described as ?Tyrannosaurus sp. This isolated right lacrimal was originally collected alongside the holotype specimen of Deinosuchus rugosus, a giant crocodilian, and remained undescribed until its re-identification as belonging to a tyrannosaurid theropod in the 1980s by paleontologist Dale Russell. The lacrimal closely resembles those of Tyrannosaurus rex in both size and morphology. Notably, it lacks the "lacrimal horn" typically present in earlier tyrannosaurids like Albertosaurus and Gorgosaurus, instead exhibiting a distinct rugosity along the dorsal surface—consistent with T. rex and its Asian relative Tarbosaurus. The specimen's considerable size places it within the range of known T. rex individuals, suggesting the presence of large tyrannosaurids during the Campanian stage (~75 million years ago), a temporal range earlier than the established Maastrichtian age (~68–66 Ma) for Tyrannosaurus rex.
Sources: en.wikipedia.org
== Predicted properties == Very few properties of rutherfordium or its compounds have been measured; this is due to its extremely limited and expensive production and the fact that rutherfordium (and its parents) decays very quickly. A few singular chemistry-related properties have been measured, but properties of rutherfordium metal remain unknown and only predictions are available.
=== Discontinuation === The British National Formulary recommends a gradual withdrawal when discontinuing antipsychotics to avoid acute withdrawal syndrome or rapid relapse. Symptoms of withdrawal commonly include nausea, vomiting, and loss of appetite. Other symptoms may include restlessness, increased sweating, and trouble sleeping. Less commonly there may be a feeling of the world spinning, numbness, or muscle pains. Symptoms generally resolve after a short period of time. There is tentative evidence that discontinuation of antipsychotics can result in psychosis. It may also result in reoccurrence of the condition that is being treated. Rarely tardive dyskinesia can occur when the medication is stopped.
Liu Wenhui entered the Xikang area with around ten to twenty thousand troops of the 24th Army at his disposal, equipped with automatic weapons, mortars, and artillery. The size and strength of Liu's remaining forces, even in this diminished state, gave him much authority in dealing with local elites and in pacifying the province. To strengthen control over the local tusi of Kham, Liu ordered from 1932 onwards that all local tribal soldiers be integrated directly into the 24th Army, a measure that reportedly maintained peace in the region.
===== GPIIb/IIIa activation ===== Collagen-mediated GPVI signalling increases the platelet production of thromboxane A2 (TXA2) and decreases the production of prostacyclin. This occurs by altering the metabolic flux of platelet's eicosanoid synthesis pathway, which involves enzymes phospholipase A2, cyclo-oxygenase 1, and thromboxane-A synthase. Platelets secrete thromboxane A2, which acts on the platelet's own thromboxane receptors on the platelet surface (hence the so-called "out-in" mechanism), and those of other platelets. These receptors trigger intraplatelet signaling, which converts GPIIb/IIIa receptors to their active form to initiate aggregation.
==== Modified cellulose adhesives ==== These water-compatible adhesives are appropriate for treatments requiring a light bond. Klucel G, carboxymethyl cellulose, and methylcellulose are the most common.
Sources: en.wikipedia.org
It is usually detected by LC-MS or HPLC-UV against a reference standard. In biological matrices, metabolite targeting can improve detection. No universal immunoassay is widely available.
The compound is generally handled as light-sensitive and stored cold and dry. Stability in solution depends on solvent, concentration, and storage time. Specific degradation rates are not fully standardized.
Limited water solubility affects formulation for cell and animal studies. Organic co-solvents are often used to dissolve it. Precipitation can confound assay results if not controlled.
SR9009 is a synthetic research compound that activates the REV-ERBα and REV-ERBβ nuclear receptors. It is not an approved drug and has no established human therapeutic use. Most published biological data come from cell and rodent studies.