circadian rhythm comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-07-29. Where a claim depends on a specific study, the study is described rather than over-claimed.
Analytical methods for SR9009 typically rely on liquid chromatography coupled with tandem mass spectrometry. The technique can separate the parent compound from related substances and detect low concentrations in biological matrices. Urine and blood are common samples in anti-doping testing, while in vitro studies may use cell culture media. Rapid metabolism and low expected concentrations make method validation important for reliable identification. Exact metabolite patterns can vary by species and are not fully mapped.
Regulatory treatment of SR9009 reflects its investigational status. The compound has no approved human therapeutic indication, and sports authorities prohibit its use. It appears on anti-doping lists as a non-approved substance or metabolic modulator, depending on the list version. Products sold online as research chemicals are not quality-controlled medicines, so their identity and purity can differ from the label. Such products may also contain unlisted compounds, which complicates both testing and safety assessment.
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.
SR9009 is generally described as poorly soluble in water and more soluble in organic solvents such as dimethyl sulfoxide and ethanol. Stock solutions are commonly prepared in an organic solvent before dilution into an aqueous buffer or vehicle. Precipitation can occur if the organic fraction is reduced too quickly or if the final concentration exceeds the compound's solubility limit. Sonication or gentle warming may aid dissolution in some protocols, but excessive heat can promote degradation. Container material and pH can also influence observed solubility.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not approved for human use | Investigational status in most countries |
| Sports status | Prohibited by WADA | Classified as non-approved or metabolic modulator |
| Common analytical method | LC-MS/MS | Used for trace detection in biological samples |
| Typical test matrices | Urine and blood | Sample choice depends on testing program |
| Human trial data | None published | Effects and safety are not established |
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.
At the molecular level, SR9009 binds the ligand-binding domain of REV-ERB and strengthens recruitment of corepressor proteins such as NCoR and HDAC3. This increases repression of target genes, including Bmal1 and other clock-controlled and metabolic genes. In rodent studies, such changes have been linked to altered lipid handling, glucose metabolism, and energy expenditure. The precise chain of events between receptor binding and whole-body effects remains an active area of research. Findings in animals do not automatically translate to humans.
Laboratory samples of SR9009 are typically handled as research chemicals rather than pharmaceuticals. Suppliers usually state that the material is for research use only and not for human or veterinary administration. Storage recommendations generally call for a freezer at approximately −20 °C, protection from light, and a desiccated environment. The solid is often described as a white to off-white powder. Solubility is commonly reported in organic solvents such as dimethyl sulfoxide and ethanol, with low solubility in water.
Analytical identification and purity assessment often use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Liquid chromatography–tandem mass spectrometry is used to detect and quantify SR9009 in biological matrices, including urine and blood, for anti-doping or pharmacokinetic studies. Nuclear magnetic resonance spectroscopy can confirm molecular structure. Stability depends on form and storage: the solid is generally more stable than solutions, and repeated freeze–thaw cycles may degrade samples. Purity is typically reported as a percentage from a certificate of analysis.
=== Additional functional domains === Apart from domains directly involved in catalytic activity further functional domains are present in the CK1δ protein. A kinesin homology domain (KHD) as well as a putative dimerization domain (DD) can be found in the kinase domain. While the KHD allows CK1 isoforms to interact with components of the cytoskeleton. the DD is supposed to be involved in regulation of kinase activity (see below). In the C-lobe, furthermore, a nuclear localization signal (NLS) as well as a centrosome localization signal (CLS) can be found. However, the first one is not sufficient to locate CK1δ to the nucleus.
=== Recurring === Artemis Pebdani as Vice President Susan Ross Kate Burton as Sally Langston, former vice president George Newbern as Charlie Ricardo Chavira as Governor Francisco Vargas of Pennsylvania Mía Maestro as Elise Martin Gregg Henry as Hollis Doyle Norm Lewis as Senate Majority Leader Edison Davis Joelle Carter as Vanessa Moss Erica Shaffer as News Reporter Mackenzie Astin as Noah Baker John Prosky as Senator Gibson Rose Abdoo as Senator Linda Moskowitz Romy Rosemont as Patty Snell Paul Adelstein as Leo Bergen Brian Letscher as Tom Larsen Matthew Del Negro as Michael Ambruso Annabeth Gish as Lillian Forrester Danny Pino as Alejandro "Alex" Vargas
July 1971: The association "Choisir la cause des femmes" is created — with philosopher Simone de Beauvoir and lawyer Gisèle Halimi — to demand the repeal of the 1920 law criminalizing abortion. January 3, 1972: Law on parentage. It opens the right for the mother to challenge, under certain conditions, the presumption of the husband's paternity. January 3, 1972: Law on the stay-at-home mother's allowance. April 24, 1972: Decree applying Article 4 of Law 67-1176 of December 28, 1967, on birth control and repealing Articles L. 648 and L. 649 of the Public Health Code. July 13, 1972: Law establishing the general status of military personnel; access to military careers is not subject to sex-based discrimination. August 16, 1972: Decree on the specific status of the corps of national police inspectors, in which women are allowed to apply. December 22, 1972: Law affirming the principle of equal pay between genders. January 2, 1973: Law on the Labor Code, which updates it and includes provisions on women's work. January 9, 1973: Law amending and supplementing the French Nationality Code and concerning certain provisions related to French nationality; it notably authorizes the transmission of nationality by the mother to her child, whether the child is "legitimate or illegitimate." March 23, 1973: Decree establishing the special status of female military corps.
Sources: en.wikipedia.org
These games have no use, and they are harmful and a waste of time.” In 2016, Saleh al-Fawzan has issued other rulings that have drawn attention in Western media, including a fatwa reportedly prohibiting the mobile game Pokémon Go, which he classified as a form of gambling. He has also been reported to consider photography generally prohibited except when necessary. In 2017, he was reported to have referred to Shia Muslims as "brothers of Satan" and stated that they are "infidels" who "lie about God, his prophet, and the consensus of Muslims", remarks that have been cited as an example of sectarian rhetoric among some Saudi clerics. Al-Fawzan's supporters argue that his statements reflect traditional jurisprudence and adherence to Salafi teachings while critics contend that his pronouncements promote intolerance and discourage reform.
A PSMA scan is a nuclear medicine imaging technique used in the diagnosis and staging of prostate cancer. It is carried out by injection of a radiopharmaceutical with a positron or gamma emitting radionuclide and a prostate-specific membrane antigen (PSMA) targeting ligand. After injection, imaging of positron emitters such as gallium-68 (68Ga), copper-64 (64Cu), and fluorine-18 (18F) is carried out with a positron emission tomography (PET) scanner. For gamma emitters such as technetium-99m (99mTc) and indium-111 (111In) single-photon emission computed tomography (SPECT) imaging is performed with a gamma camera. As well as the diagnosis and staging of prostate cancer, PSMA imaging can also be used to assess suitability for and plan treatment with external beam radiotherapy and PSMA-targeted radionuclide therapy.
=== Towards type IV === Zoltan Galántai notes that neither Kardashev nor Sagan thought to extend the scale and define a Type IV (which would use the energy of an entire universe). They simply did not envision a civilization capable of manipulating its environment on the largest possible scale (about 14 billion parsecs). The concept of a Type IV supercivilization approaches divine possibilities, enabling the creation of, and travel through, alternate universes of such a civilization's own design, although the latter possibility is reserved for a Type V civilization by Carrigan. The fraction of energy captured by a civilization capable of powering itself on a black hole could also be used to classify civilizations.
Sources: en.wikipedia.org
No. It is an investigational compound without approved therapeutic indications. It is sold for research purposes only in many jurisdictions.
Sports authorities prohibit it because it is not approved for human use and has potential performance-enhancing effects. It appears on anti-doping lists under non-approved or metabolic modulator categories.
Detection usually uses liquid chromatography-tandem mass spectrometry. The method targets the parent compound or its metabolites in urine or blood.
Liquid chromatography with mass spectrometry is a common approach. Ultraviolet detection and nuclear magnetic resonance can support identification when suitable standards are available.