A practical reference on LC-MS/MS: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-04-28. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Common name | SR9009 | Also referred to as Stenabolic in non-scientific contexts. |
| Chemical class | Synthetic small molecule | Not a steroid or peptide hormone. |
| Receptor target | REV-ERBα and REV-ERBβ | Nuclear receptor agonist in preclinical studies. |
| Development status | Investigational | No approved human therapeutic indication. |
| Regulatory attention | Prohibited in sport | Listed by anti-doping authorities. |
Storage recommendations for SR9009 reference material typically specify a freezer at -20 °C or lower, with protection from moisture and light. Repeated freeze-thaw cycles can degrade small molecules and introduce variability. Stock solutions in dimethyl sulfoxide are often aliquoted to avoid repeated handling. Stability studies may examine degradation under heat, humidity, and light exposure. The compound's thiophene and nitro groups can participate in reactions that alter analytical signals over time, so such changes affect quantitative results.
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.
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.
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.
In rodent studies, SR9009 has been reported to increase mitochondrial content in skeletal muscle and improve exercise endurance under some conditions. These findings led to popular descriptions such as an exercise mimetic, although that term oversimplifies the biology. Effects vary by dose, timing, tissue, and model. The compound's influence on circadian pathways means that time of administration can matter in experiments. Whether similar metabolic changes occur in humans remains largely unexplored in controlled published trials.
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.
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.
Librarian Ainsworth Rand Spofford, who directed the Library of Congress from 1865 to 1897, built broad bipartisan support to develop it as a national library and a legislative resource. He was aided by expansion of the federal government after the war and a favorable political climate. He began comprehensively collecting Americana and American literature, led the construction of a new building to house the library, and transformed the librarian of Congress position into one of strength and independence. Between 1865 and 1870, Congress appropriated funds for the construction of the Thomas Jefferson Building, placed all copyright registration and deposit activities under the library's control, and restored the international book exchange. The library also acquired the vast libraries of the Smithsonian and of historian Peter Force, strengthening its scientific and Americana collections significantly. By 1876, the Library of Congress had 300,000 volumes; it was tied with the Boston Public Library as the nation's largest library. It moved from the Capitol building to its new headquarters in 1897 with more than 840,000 volumes, 40 percent of which had been acquired through copyright deposit. A year before the library's relocation, the Joint Library Committee held hearings to assess the condition of the library and plan for its future growth and possible reorganization. Spofford and six experts sent by the American Library Association testified that the library should continue its expansion to become a true national library.
== Interactions == GSTP1 has been shown to interact with Fanconi anemia, complementation group C and MAPK8. GST-Pi is expressed in many human tissues, particularly in the biliary tree, renal distal convoluted tubules and lungs.
==== Key physiological parameters in pharmacokinetics include ==== Half-life (t½) – The time required for the drug's plasma concentration to reduce by half. Volume of distribution (VD) – A theoretical volume that relates the total amount of a drug in the body to its measured concentration in the blood (or plasma). Total Clearance (Cltot) – A theoretical pharmacokinetic parameter that statistically explains the efficiency with which a drug is irreversibly eliminated from the body, quantified as the volume of plasma cleared of the drug per unit of time, typically measured in L/h or mL/min. Area Under the Curve (AUC) – The definite integral of the plasma drug concentration versus time curve from time zero to infinity, which represents the total systemic exposure of the body to a drug overtime (AUC0−∞).
=== Variation === The formyl group is not strictly required for initiation. Bacteria with their formyltransferase knocked out, which prevents Met-tRNAfMet (i.e. methionine loaded onto tRNAfMet) from turning into fMet-tRNAfMet, can have varying degrees of residual ability to start protein synthesis. E. coli, S. pneumoniae and B. subtilis show almost no remaining translation ability, while P. aeruginosa, S. aureus, H. influenzae, and possibly S. faecalis still churn out plenty of protein. In P. aeruginosa, this ability is facilitated by bacterial initiation factor 2, which can carry both Met-tRNAfMet and fMet-tRNAfMet to the ribosome.
== Definition == The defining feature of smoking-related interstitial fibrosis is a distinctive/unique type of fibrosis characterized by "ropey" collagen bundles within the walls of the air sacs (alveoli), almost always in association with other smoking-related abnormalities such as pigmented macrophages and emphysema.
Sources: en.wikipedia.org
=== Media === Bob Barker Studio at CBS Television City named in his honor. Time magazine's Greatest Game Show Host of All-Time GSN Lifetime Achievement Award MTV Movie Award for Best Fight in Happy Gilmore (with Adam Sandler)
PUFA-fortified foods available on the market have been increasing since epidemiological and clinical researches have revealed possible effects of PUFA on brain development and curative and/or preventive effects on cardiovascular disease. However, PUFA are very labile and easily oxidizable, thus the maximum beneficial effects of PUFA supplements may not be obtained if they contain significant amounts of toxic OαβUAs, which as commented on above, are being considered as possible causal agents of numerous diseases. Special attention must also be paid to cooking oils used repeatedly in catering and households because in those processes very high amounts of OαβUAs are generated and they can be easily absorbed through the diet.
==== Educator tax deduction ==== Previously, educators could take a tax deduction for unreimbursed education costs of up to $300 per year (or $600 if married filing jointly) without itemizing their tax deductions. Effective January 1, 2026, eligible educators may also take an itemized tax deduction for unreimbursed education costs in excess of $300 per year (or $600 if married filing jointly). In order to qualify, the individual must work at any K–12 school for least 900 hours during the school year as a teacher, instructor, counselor, principal, aide, interscholastic sports coach, or sports administrator. The unreimbursed education costs must be directly related to the individual's work as an educator. Eligible unreimbursed education costs include books, supplies, other classroom materials, equipment, professional development courses or training that is related to the curriculum or student instruction.
TikTok tends to appeal to younger users, as 41% of its users are between the ages of 16 and 24. As of 2021, these individuals are considered Generation Z. TikTok's geographical use in 2019 has shown that 43% of new users were from India before the social platform was banned in the country. But adults have also seen growth on TikTok. The share of US adults who regularly get news from TikTok hit 5% in 2025. By July 2023, TikTok has become the primary news source for British teenagers on social media, with 28% of 12 to 15-year-olds relying on the platform, while traditional sources like BBC One/Two are more trusted at 82%, according to a report by UK regulator Ofcom. As of the first quarter of 2022, there were over 100 million monthly active users in the United States and 23 million in the UK. The average user, daily, was spending 1 hour and 25 minutes on the app and opening TikTok 17 times. Out of TikTok's top 100 male creators, a 2022 analysis reported 67% were white, with 54% having near-perfect facial symmetry.
Sources: en.wikipedia.org
It is a synthetic compound studied as an agonist of REV-ERB nuclear receptors. It is not an approved medicine and has mainly been examined in laboratory and animal research.
No. It is a small molecule that binds nuclear receptors involved in circadian regulation. Its classification differs from anabolic steroids or peptide hormones.
Published human clinical trial data are lacking. Most safety and activity information comes from preclinical models, so effects in people remain uncertain.
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.