A practical reference on reference standard: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-05-07 and is reviewed periodically as new material appears.
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.
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 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 |
|---|---|---|
| Regulatory status | Not approved for human use | Research-use-only status in many markets |
| WADA status | Prohibited in sport | Generally listed as a non-approved substance |
| Detection technique | LC-MS/MS | Common for urine and blood analysis |
| Common alias | Stenabolic | Informal market nickname, not a pharmacopoeial name |
| Purity check | HPLC or LC-UV | Independent certificate of analysis is typical |
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.
Physicochemical behavior influences handling. SR9009 is described as a solid with limited aqueous solubility, so organic solvents such as dimethyl sulfoxide or ethanol are common in research stock solutions. Aqueous dilution can produce precipitates if the organic content is too low. Light, heat, and repeated freeze-thaw cycles may affect stability. Storage recommendations usually specify a desiccated freezer environment protected from light, but exact stability data depend on the formulation and matrix.
Mechanistically, SR9009 binds the ligand-binding domain of REV-ERBα/β and enhances recruitment of corepressor complexes. This represses target genes rather than activating them. Because REV-ERB proteins normally compete with ROR proteins at shared response elements, the net effect depends on tissue and timing. Researchers use SR9009 to probe how nuclear receptor signaling links the clock to metabolism, inflammation, and muscle biology. Findings are largely preclinical, and the precise contribution of each receptor subtype remains under study.
SR9009 is frequently discussed in fitness and research-chemical contexts, yet it has no approved medical indication. Regulatory agencies have not authorized it for human use, and it is not a standard prescription drug. Some sports organizations list it as a prohibited substance because of its potential performance-enhancing properties. Published human data are sparse, so claims about its effects in people often rely on animal models or anecdotal reports. Quality and identity of online materials can vary widely.
SR9009 is a synthetic small molecule studied as a REV-ERB agonist. REV-ERBα and REV-ERBβ are nuclear receptors that help regulate circadian rhythms and metabolic gene expression. The compound was identified in academic screening efforts to find synthetic ligands for these receptors. In cell and animal studies, SR9009 alters transcription of genes involved in lipid and glucose metabolism, and it can shift circadian behavior. It is not an approved therapeutic agent.
Scientific discussion of SR9009 often separates animal evidence from human anecdote. Rodent studies provide controlled data on endurance, metabolism, and gene expression, but they use specific strains, doses, and treatment durations. Human reports are mostly uncontrolled and cannot establish cause and effect. Open questions include oral bioavailability, tissue distribution, metabolic stability, and long-term effects. Review articles generally call for more rigorous pharmacokinetic and safety research before any clinical use could be considered.
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.
Arthrodesis, also known as joint fusion, is the artificial induction of joint ossification between two bones by surgery. This is done to relieve intractable pain in a joint which cannot be managed by pain medication, splints, or other normally indicated treatments. The typical causes of such pain are fractures which disrupt the joint, severe sprains, and arthritis. It is most commonly performed on joints in the spine, hand, ankle, and foot. Historically, knee and hip arthrodeses were also performed as pain-relieving procedures, but, with the great successes achieved in hip and knee arthroplasty, arthrodesis of these large joints has fallen out of favour as a primary procedure and now is only used as a last resort in some failed arthroplasties.
Live Science reported that lead author of the study Matteo Borrini from Liverpool John Moores University stated: "these cannot be real bloodstains from a person who was crucified and then put into a grave, but actually handmade by the artist that created the shroud." In 2025 a study was published in the journal Archaeometry, by Brazilian digital graphics expert and 3D designer Cicero Moraes. Moraes used software to model how clothing would move on a three-dimensional human body compared to a low-relief sculpture. In Moraes’s experiments, the image produced when a cloth is draped over a 3D human model appears misshapen and distorted. This is called the Agamemnon Mask effect, named after the Mycenaean gold funerary mask. Moraes also found that the imprint made from a low-relief sculpture closely matched the image on the Turin shroud. This supports his conclusion that the image on the shroud was an artistic creation, which Moraes interpreted as being a funerary object and a "masterwork of Christian art."
A sausage roll is a savoury dish, popular in current and former Commonwealth nations, consisting of sausage meat wrapped in puff pastry. Although variations are known throughout Europe and in other regions, the sausage roll is most closely associated with British cuisine. The British bakery chain Greggs sells around 2.5 million sausage rolls per week, or around 140 million per year.
2C-B acts as a potent partial agonist of the serotonin 5-HT2 receptors, including of the serotonin 5-HT2A and 5-HT2C receptors and to a lesser extent of the serotonin 5-HT2B receptor. In one study, it had EC50Tooltip half-maximal effective concentration (EmaxTooltip maximal efficacy) values of 1.2 nM (101%) at the serotonin 5-HT2A receptor, 13 nM (97%) at the serotonin 5-HT2B receptor, and 0.63 nM (98%) at the serotonin 5-HT2C receptor. In earlier studies, 2C-B was found to be a low-efficacy serotonin 5-HT2A and 5-HT2C receptor partial agonist or even antagonist. However, subsequent studies have consistently found higher efficacy of 2C-B at these receptors. In addition to the serotonin 5-HT2 receptors, 2C-B also shows lower affinity for other serotonin receptors, such as the serotonin 5-HT1A and 5-HT1B receptors among others. However, while 2C-B itself was not assessed, other 2C derivatives showed little activity as serotonin 5-HT1A receptor agonists (EC50 = >3,000 nM). At the serotonin 5-HT2A receptor, 2C-B has subsequently been identified as a biased agonist, acting as a near-full agonist of receptor in terms of Ca2+ mobilization (EC50 = 1.64 nM; Emax = 92.6%) but with 6-fold lower potency as a moderate-efficacy partial agonist in terms of β-arrestin2 recruitment (EC50 = 10.0 nM; Emax = 60.1%). However, serotonin itself showed about 42-fold greater potency in activating Ca2+ mobilization than β-arrestin2 signaling in the study. The implications of the preceding findings are not fully clear.
Sources: en.wikipedia.org
If the reaction is more complicated, then the output is not uniquely determined by the RTD. It also depends on the degree of micromixing, the mixing between molecules that entered at different times. If there is no mixing, the system is said to be completely segregated, and the output can be given in the form
George Szirtes (born 29 November 1948); poet and translator; opposes Boycott, Divestment and Sanctions movement and was a signatory to the Euston Manifesto; was judge for the 2017 Griffin Poetry Prize; has won a variety of prizes for his work, most recently the 2004 T. S. Eliot Prize, for his collection Reel, and the Bess Hokin Prize in 2008 for poems in Poetry magazine. His translations from Hungarian poetry, fiction and drama have also won numerous awards; has received an Honorary Fellowship from Goldsmiths College, University of London Arthur Waley (born Arthur David Schloss, 19 August 1889 – 27 June 1966); produced works on Theravada Tripiṭaka Sutta Piṭaka and Abhidhamma Piṭaka texts, as well as developing translations of works by Chuang Tzu, Lao Tzu, and writing his own perspectives and contemplations on the key Mahayana wisdom scriptures. Amongst his honours were the CBE in 1952, the Queen's Gold Medal for Poetry in 1953, and he was invested as a Companion of Honour in 1956. Humbert Wolfe, poet and civil servant
=== Surgery === Wounds requiring surgical closure with skin grafts or flaps (typically anything more than a small full thickness burn) should be dealt with as early as possible. Circumferential burns of the limbs or chest may need urgent surgical release of the skin, known as an escharotomy. The aim is to release the pressure from the underlying deeper tissue and enable ventilation to the lungs and circulation to the limb . It is uncertain if it is useful for neck or digit burns. Fasciotomies may be required for electrical burns. Skin grafts can involve temporary skin substitutes, derived from animal (human donor or pig) skin or synthesized. They are used to cover the wound as a dressing, preventing infection and fluid loss, but will eventually need to be removed. Alternatively, human skin can be treated to be left on permanently without rejection. There is no evidence that the use of copper sulphate to visualise phosphorus particles for removal can help with wound healing due to phosphorus burns. Meanwhile, absorption of copper sulphate into the blood circulation can be harmful.
Sources: en.wikipedia.org
== History == Guzman y Gomez was established by Steven Marks, a New Yorker who previously worked as a hedge fund manager. After relocating to Australia, he found the quality of Mexican food to be poor and decided to start a restaurant. He has stated that "real Mexican is really urban, street and hot [...] Latin people are so full of energy and full of life, we wanted to bring that to Australia". He took on his friend Robert Hazan, another New Yorker, as a partner. They named the business after two of Marks' childhood friends. The first store was opened in King Street, Newtown, Sydney, in 2006. Store openings in Bondi Junction and Kings Cross, followed within a year. By April 2012, there were 12 stores. The first Guzman y Gomez in the Melbourne central business district opened in November 2012. Within 12 years, they opened 100 stores in Australia. The first international Guzman y Gomez restaurant opened at the end of 2013 in Singapore, followed thereafter by the opening of a restaurant in Tokyo, Japan, in April 2015. In January 2020, Guzman y Gomez's international expansion continued with the opening of their first restaurant in the United States in the Chicago suburb of Naperville. In May 2026, Guzman y Gomez announced the closure of all of their restaurants in the United States.
=== Identification of Cell-binding Peptides === Bacterial display can be used to find peptides which bind to specific cells e.g. breast cancer cells or stem cells. Displayed proteins are fluorescently tagged with GFP, so binding interactions between peptides and target cells can be seen by flow cytometry. Control samples are required in order to measure fluorescence levels in the absence of displayed peptides. Samples are also required which don’t contain displayed peptides, but contain mammalian cells and bacterial cells (including the scaffold).
== Application == Due to the hemolytic toxicity of Guanacastepene A, it is not currently used directly in human clinical medicine. Its main potential, however, lies in its function as a "resistance breaker" against antibiotic-resistant pathogens, as various experiments have demonstrated its efficacy against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE). Furthermore, a more specific area of application arises in antifungal research, as newly isolated members of the guanacastane family, such as guanacastepene V, isolated from the marine fungus Coprinellus xanthothrix discovered on the surface of a barnacle off the coast of Japan (Kashima City), exhibit a selective effect against the yeast Candida auris. This species is considered an emerging multidrug-resistant yeast. Although guanacastepene V inhibits the growth of Candida auris with an MIC of 6.25 µg/ml, it also exhibits high selectivity, as it has virtually no effect on Candida albicans at an MIC of 100 µg/ml. Therefore, opportunities may arise to further develop other members of the guanacastane family to combat Candida albicans outbreaks in hospitals. Guanacastepene A also serves as a challenging target molecule for total chemical synthesis, making it useful for developing and testing novel synthetic methods; examples include the controlled fragmentation of cyclobutane rings or innovative variants of the Robinson annulation reaction for constructing complex seven-membered ring systems.
== Background == During the Busan Summit on October 30, 2025, US president Donald Trump invited Chinese leader Xi Jinping to visit the United States at an appropriate time. During his May 2026 state visit to China, Trump invited Xi to the White House in September. On July 23, Trump said that Xi would be visiting on 24 September. On September 4, Reuters reported that Xi would be travelling with a large business delegation. However, The Wall Street Journal reported on September 22 that Xi was unlikely to bring a business delegation. This was Xi's first visit to the White House after 11 years. The state dinner was also the second one held during the second Trump administration, following the one held for King Charles III during his state visit in April 2026. On September 20, 2026, Chinese vice premier He Lifeng met with US secretary of treasury Scott Bessent and Trade Representative Jamieson Greer in New York City, where they agreed to set up an AI dialogue. On September 21, the Chinese foreign ministry announced that Xi would pay a state visit to the US from September 23 to 25. The ministry spokesperson Guo Jiakun said that two heads of state's reciprocal visits within a six-month period are "of historic, milestone significance". On September 23, Chinese ambassador to the US Xie Feng wrote an article in the People's Daily, saying China and the US should manage their differences in good faith, and that the US should stop fabricating pretexts such as national security, economic imbalances and forced labor in trying to constrain China.
Sources: en.wikipedia.org
Legality depends on the country and the intended use. In many places it is not approved as a medicine and may be sold only as a research chemical. Importation or possession can be restricted, and sports organizations prohibit it.
Anti-doping laboratories typically use LC-MS/MS to detect SR9009 or its metabolites in urine or blood. The exact assay depends on the laboratory and the testing program. Detection can be challenging because the compound may be rapidly metabolized and present at low levels.
Stenabolic is an informal nickname used in online fitness and research-chemical markets, not an official drug name. It likely references reported effects on endurance in rodent studies. The nickname does not imply approval or proven human benefit.
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.