If you have been reading about freeze-thaw cycle 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 2025-10-26. Where a claim depends on a specific study, the study is described rather than over-claimed.
SR9009 is often grouped with compounds studied for circadian and metabolic regulation rather than with classical anabolic steroids. Its interactions with nuclear receptors differ from those of androgen receptor ligands, and its proposed mechanisms involve transcriptional control rather than direct hormone signaling. Some sources classify it as a metabolic modulator because of observed effects on energy utilization. The distinction matters for regulation and for interpreting research results across different compound classes.
SR9009 is a synthetic small molecule developed as a REV-ERB agonist. It binds to REV-ERBα and REV-ERBβ, nuclear receptors that help regulate circadian rhythms and metabolic gene expression. In cell and animal studies, the compound alters lipid and glucose handling and influences skeletal muscle oxidative capacity. Its exact effects in humans remain largely uncharacterized because controlled clinical trials have not been reported. The molecule is frequently described in preclinical literature as a metabolic modulator.
Research interest in SR9009 grew from studies showing improved running endurance in mice after short treatment periods. Those experiments linked the compound to increased mitochondrial content and fatty acid oxidation in muscle, but the findings come from animal models and specific dosing schedules. Independent replication has been limited, and the pathways connecting REV-ERB activation to exercise performance are still being mapped. Whether similar responses occur in humans is an open question.
Identity and purity testing for SR9009 commonly uses liquid chromatography coupled with tandem mass spectrometry. This method separates the compound from matrix components and detects it by mass-to-charge transitions, providing sensitive and specific confirmation. Nuclear magnetic resonance spectroscopy can support structural identification, while high-performance liquid chromatography with ultraviolet detection may estimate purity. Because online products labeled as SR9009 may contain other substances or no active compound at all, independent verification is important in research settings. Certificates of analysis are useful but not a substitute for in-house testing.
Laboratory samples of SR9009 are typically supplied as a white to off-white powder. The compound dissolves readily in organic solvents such as dimethyl sulfoxide and ethanol, while its solubility in water is low. Because of this solubility profile, researchers often prepare concentrated stock solutions in an organic solvent before diluting them into aqueous assay buffers. Light exposure, moisture, and repeated freeze-thaw cycles can degrade many small molecules, so handling procedures usually aim to minimize these factors. Purity is commonly checked before use.
Storage conditions for research-grade SR9009 generally involve a freezer at approximately minus twenty degrees Celsius, sometimes lower for long-term preservation. Containers should remain tightly closed and protected from light. Desiccants may be used to limit moisture uptake. Solutions are often stored in aliquots to avoid repeated warming and cooling. Stability data for the compound under various conditions are limited, so laboratories typically follow supplier recommendations and verify performance through periodic analytical checks rather than assuming indefinite stability.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C20H24ClN3O4S | Reported for the free base |
| Molecular weight | 437.9 g/mol | Calculated from the formula |
| Primary target | REV-ERBα and REV-ERBβ | Nuclear receptors involved in circadian regulation |
| Solubility | Soluble in DMSO and ethanol | Poorly soluble in water |
| Typical storage | -20 °C, desiccated | Protect from light and moisture |
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.
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.
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.
Quality control for research materials includes identity confirmation by nuclear magnetic resonance and purity assessment by high-performance liquid chromatography. Mass spectrometry provides molecular weight confirmation and can detect related impurities. Purchasers should request a certificate of analysis that lists lot-specific data. Online products advertised for human use often lack such documentation. Distinguishing legitimate research material from mislabeled or contaminated samples is a recurring challenge in independent testing, and independent laboratories may use orthogonal methods to verify identity.
Detection of SR9009 in biological samples usually relies on liquid chromatography coupled to tandem mass spectrometry. This approach separates the compound from matrix components and identifies it by mass transitions. Because SR9009 can undergo metabolism, laboratories often look for both parent drug and specific metabolites. Sample preparation may involve protein precipitation or solid-phase extraction. Method validation examines sensitivity, carryover, and interference from related substances, and reference standards are required for accurate calibration.
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.
=== Competitive === The binding of oxygen is affected by molecules such as carbon monoxide (for example, from tobacco smoking, exhaust gas, and incomplete combustion in furnaces). CO competes with oxygen at the heme binding site. Hemoglobin's binding affinity for CO is 250 times greater than its affinity for oxygen. Since carbon monoxide is a colorless, odorless, and tasteless gas, and poses a potentially fatal threat, carbon monoxide detectors have become commercially available to warn of dangerous levels in residences. When hemoglobin combines with CO, it forms a very bright red compound called carboxyhemoglobin, which may cause the skin of CO poisoning victims to appear pink in death, instead of white or blue. When inspired air contains CO levels as low as 0.02%, headache and nausea occur; if the CO concentration is increased to 0.1%, unconsciousness will follow. In heavy smokers, up to 20% of the oxygen-active sites can be blocked by CO. In similar fashion, hemoglobin also has competitive binding affinity for cyanide (CN−), sulfur monoxide (SO), and sulfide (S2−), including hydrogen sulfide (H2S). All of these bind to iron in heme without changing its oxidation state, but they nevertheless inhibit oxygen-binding, causing grave toxicity. The iron atom in the heme group must initially be in the ferrous (Fe2+) oxidation state to support oxygen and other gases' binding and transport (it temporarily switches to ferric during the time oxygen is bound, as explained above).
=== Final weeks on the Gulf Coast === Filming resumed on July 19. The sandpit fight scene between Bosworth and pro wrestler Tom Magee was shot in Bay St. Louis. It was aborted after a first attempt where Bosworth clipped Magee's cheek with a punch, and finished two weeks later on August 9. While a King Features gossip column claimed that the botch had led to a real scuffle, Bosworth himself assured that the accident had been handled in a civil manner by both. The final scene shot on the Gulf Coast was a gas station explosion on Daisy Vestry Road in Latimer on August 10.
Representative James Talarico legislative website Talarico for Texas U.S. Senate campaign website Financial information (federal office) at the Federal Election Commission Profile at Vote Smart Appearances on C-SPAN
Epidemiological studies have shown a clear association between breathing high concentrations of radon and incidence of lung cancer. Radon is a contaminant that affects indoor air quality worldwide. Because radon is denser than air it accumulates in basements and crawlspaces under dwellings. According to the United States Environmental Protection Agency (EPA), radon is the second most frequent cause of lung cancer, after cigarette smoking, causing 21,000 lung cancer deaths per year in the United States. About 2,900 of these deaths occur among people who have never smoked. While radon is the second most frequent cause of lung cancer, it is the number one cause among non-smokers, according to EPA policy-oriented estimates. Significant uncertainties exist for the health effects of low-dose exposures. Due to local differences in geology, the level of exposure to radon gas differs by location.
This ratio is commonly known as the turnover time or flushing time. When applied to liquids, it is also known as the hydraulic retention time (HRT), hydraulic residence time or hydraulic detention time. In the field of chemical engineering this is also known as space time. The residence time of a specific compound in a mixture equals the turnover time (that of the compound, as well as that of the mixture) only if the compound does not take part in any chemical reaction (otherwise its flow is not conservative) and its concentration is uniform. Although the equivalence between the residence time and the ratio
Sources: en.wikipedia.org
He held a very wide variety of posts, included Member, Governing Body, Royal Academy of Music, 1967–1979, Director, Central Statistical Office, 1968–1978, BBC Music Advisory Committee, 1971–1983, Visiting Fellow, Nuffield College, Oxford, 1972–1980, Chairman, Royal Opera House, Covent Garden, 1974–1987, Director, N M Rothschild & Sons, 1978–1990 (Vice-chairman, 1978–1984), President, Royal Statistical Society, 1978–1980, Chairman, Economist Intelligence Unit, 1979–1983, Warden of Wadham College, Oxford, 1984–1993, Chancellor, Keele University, 1986–2002, Trustee, London Philharmonic Orchestra, 1988–2000, President, British Association for the Advancement of Science, 1989–1990, Pro-Vice-Chancellor, University of Oxford, 1991–1993, Chairman, British Museum Development Trust, 1993–2003, later Chairman Emeritus, Chancellor, Open University of Israel, 1994–2004 Moss, Celia (1819-1873 and Marion (1821-1901), Anglo-Jewish writers and educators, authors of poetry, prose and fiction, Marion Moss Hartog established the first Jewish women's periodical, the Jewish Sabbath Journal: A Penny and Moral Magazine for the Young, which foundered after it was attacked by the Jewish Chronicle.
2018 results of the TIME trial, which used a randomized, double-blind, placebo-controlled trial design, concluded that "bone marrow mononuclear cells administration did not improve recovery of LV function over 2 years" in people who had a myocardial infarction. Accordingly, the BOOST-2 trial conducted in 10 medical centers in Germany and Norway reported that the trial result "does not support the use of nucleated BMCs in patients with STEMI and moderately reduced LVEF". Furthermore, the trial also did not meet any other secondary MRI endpoints, leading to a conclusion that intracoronary bone marrow stem cell therapy does not offer a functional or clinical benefit. In 2021, stem cell injections in the US have caused grave infections in at least 20 patients who received umbilical cord blood-derived products marketed as "stem cell treatment". In 2023, the case of a woman who was infected with Mycobacterium abscessus and sustained meningitis after stem cell treatment for multiple sclerosis at a commercial clinic in Baja California, Mexico was published.
The logic of this was that if McCarthyists were accusing so many people of being communist agents, it could only be to divert attention from the real communists. The theme of collusion between international communists and Western rightists would be picked up again by many movies (Goldfinger, A View to a Kill) or television shows (episodes of MacGyver or Airwolf), which would feature an alliance between power-hungry communists attacking the free world from the outside and profit-driven capitalists undermining it for financial gain. The Ugly American by William J. Lederer and Eugene Burdick. Originally published in 1958, this book tells the story of how the US government handled foreign policy very poorly. The main character, Homer Atkins, discovers this sad truth when he is dispatched to the fictitious country of Sarkhan (in Southeast Asia.) One Day in the Life of Ivan Denisovich by Alexander Solzhenitsyn. This acclaimed book, first published in 1962, exposed the horrors of the Russian prison camps during WWII under the Stalinist regime. It is a semi-autobiographical tale about a dutiful soldier who is sent to a Siberian camp, after being falsely accused of treason. Solzhenitsyn received the Nobel Prize in literature. Starship Troopers by Robert A. Heinlein
=== Food storage === Xerophiles are a concern to food storage industry due to their ability to bypass common food preservation methods. Many foods are preserved by creating high osmotic pressures that dry out and kill any microbes that attempt to culture in the food. Foods such as honey or jam have such high levels of sugar and low levels of water normal micro organisms can not grow on them. However, xerophilic organisms can grow in these mediums posing a threat to food safety. The common food preservation methods of reducing water activity (food drying) may not always be sufficient to prevent the growth of xerophilic organisms, often resulting in food spoilage. Some mold and yeast species are xerophilic. Mold growth on bread is an example of food spoilage by xerophilic organisms. Complete dehydration based on the freeze-drying technique with effective protection inside a tight packaging system, strictly impervious to water and atmospheric gases (O2 and CO2), may be required for long-term preservation of food and pharmacochemical substances (antibiotics, vaccines...). Freeze drying can limit the microbial activity on the long term, as long as the product remains perfectly dry in a hermetically sealed and intact package, but it is not a sterilisation technique per se, because after rehydration, even if many dehydrated cells suffer irreversible and lethal damages, some resistant spores and bacterial endospores can still be revived again, and multiplied, by means of microbiological cultures if the product was not initially sterilized by applying a proven technique.
==== Dehydrogenases: equivalents to complexes I and II ==== Bacteria can use several different electron donors. When organic matter is the electron source, the donor may be NADH or succinate, in which case electrons enter the electron transport chain via NADH dehydrogenase (similar to Complex I in mitochondria) or succinate dehydrogenase (similar to Complex II). Other dehydrogenases may be used to process different energy sources: formate dehydrogenase, lactate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, H2 dehydrogenase (hydrogenase), electron transport chain. Some dehydrogenases are also proton pumps, while others funnel electrons into the quinone pool. Most dehydrogenases show induced expression in the bacterial cell in response to metabolic needs triggered by the environment in which the cells grow. In the case of lactate dehydrogenase in E. coli, the enzyme is used aerobically and in combination with other dehydrogenases. It is inducible and is expressed when the concentration of DL-lactate in the cell is high.
Sources: en.wikipedia.org
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.
It binds to REV-ERBα and REV-ERBβ, nuclear receptors involved in circadian and metabolic gene regulation. This can alter transcription of genes related to lipid and glucose metabolism in experimental models.
No controlled human trials have established that effect. Endurance findings come primarily from rodent studies, and human responses remain unknown.
Research-grade SR9009 is typically stored frozen at about minus twenty degrees Celsius, protected from light and moisture. Stock solutions are often kept in aliquots to avoid repeated freeze-thaw cycles. Specific storage conditions should follow the supplier's documentation.