If you have been reading about LC-MS/MS 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 2025-09-10. Where a claim depends on a specific study, the study is described rather than over-claimed.
SR9009 is frequently discussed alongside other REV-ERB ligands, including synthetic agonists and natural heme-related molecules. Its selectivity for REV-ERB over related nuclear receptors has been measured in binding and reporter assays, though off-target activity at higher concentrations is possible. The compound is prohibited in sport by the World Anti-Doping Agency, and it is not approved for any medical use in major jurisdictions. Products sold online may be labeled as research chemicals, and their identity and purity are not guaranteed by regulatory review.
SR9009 is a synthetic small molecule that acts on the nuclear receptors REV-ERBα and REV-ERBβ. These receptors are part of the circadian clock machinery and normally repress transcription of certain target genes. In laboratory research, SR9009 is used as a chemical tool to study how REV-ERB activity influences metabolism, inflammation, and daily biological rhythms. The compound is not an approved medicine, and its effects in humans remain largely uncharacterized. It is often described as an investigational agent rather than a therapeutic product.
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.
| Property | Value | Notes |
|---|---|---|
| Common name | SR9009 | Also marketed informally as Stenabolic |
| Chemical class | Synthetic REV-ERB agonist | Binds REV-ERBα and REV-ERBβ |
| Molecular formula | C24H30ClN3O4S | Approximate molecular weight 492 g/mol |
| CAS Registry Number | 1379686-30-2 | Identifier for the parent compound |
| Regulatory status | Not approved for human use | Prohibited in sport by WADA |
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.
Detection of SR9009 in biological samples usually employs liquid chromatography coupled with tandem mass spectrometry. This method can identify the parent compound and sometimes metabolites in urine or blood. Because exposure can be low and clearance may be rapid, sample timing and limits of detection matter. Laboratories validate assays for sensitivity and specificity. Results are interpreted alongside chain-of-custody and quality-control records. Urine is the common matrix for anti-doping analysis, while blood may be used in research settings.
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.
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.
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.
In contrast to MRI, structural biology studies do not directly generate an image, but rely on complex computer calculations to generate three-dimensional molecular models. Currently most samples are examined in a solution in water, but methods are being developed to also work with solid samples. Data collection relies on placing the sample inside a powerful magnet, sending radio frequency signals through the sample, and measuring the absorption of those signals. Depending on the environment of atoms within the protein, the nuclei of individual atoms will absorb different frequencies of radio signals. Furthermore, the absorption signals of different nuclei may be perturbed by adjacent nuclei. This information can be used to determine the distance between nuclei. These distances in turn can be used to determine the overall structure of the protein. A typical study might involve how two proteins interact with each other, possibly with a view to developing small molecules that can be used to probe the normal biology of the interaction ("chemical biology") or to provide possible leads for pharmaceutical use (drug development). Frequently, the interacting pair of proteins may have been identified by studies of human genetics, indicating the interaction can be disrupted by unfavorable mutations, or they may play a key role in the normal biology of a "model" organism like the fruit fly, yeast, the worm C. elegans, or mice. To prepare a sample, methods of molecular biology are typically used to make quantities of protein by recombinant expression and purification from bacteria.
=== AC-driven === LEDs developed by Seoul Semiconductor can operate on AC power without a DC converter. For each half-cycle, part of the LED emits light and part is dark, and this is reversed during the next half-cycle. The efficiency of this type of HP-LED is typically 40 lm/W. A large number of LED elements in series may be able to operate directly from line voltage. In 2009, Seoul Semiconductor released a high DC voltage LED, named 'Acrich MJT', capable of being driven from AC power with a simple controlling circuit. The low-power dissipation of these LEDs affords them more flexibility than the original AC LED design.
== United Kingdom == Below are the individuals appointed by Charles III in his right as King of the United Kingdom with honours within his own gift and with the advice of the Government for other honours.
Tetramers of 222 symmetry are "dimer of dimers". Hexamers of 32 point group symmetry are "trimer of dimers" or "dimer of trimers". Thus, the nomenclature "dimer of dimers" is used to specify the point group symmetry or arrangement of the oligomer, independent of information relating to its dissociation properties. Another distinction often made when referring to oligomers is whether they are homomeric or heteromeric, referring to whether the smaller protein subunits that come together to make the protein complex are the same (homomeric) or different (heteromeric) from each other. For example, two identical protein monomers would come together to form a homo-dimer, whereas two different protein monomers would create a hetero-dimer.
Sources: en.wikipedia.org
=== August === 6 August – Tom O'Connor, journalist, author, senior citizens' advocate and local politician, president of Grey Power (2016–2018), Waimate District Councillor (since 2013) (born 1944). 8 August Judy Bailey, pianist, composer, jazz musician and educator (Sydney Conservatorium of Music), and television presenter (Play School) (born 1935). Peter Lester, sailor, sailing coach and commentator, OK dinghy world champion (1977), Admiral's Cup winner (1987, 1993) (born 1954). 10 August – Patrick Waddington, Russian linguist, literary critic and historian (Victoria University of Wellington) (born 1934). 13 August – Grant Tavinor, philosopher (Lincoln University) (born c. 1973). 15 August – John Rowan, lawyer, King's Counsel (since 1997) (born 1944). 16 August – Janet Grieve, biological oceanographer (New Zealand Oceanographic Institute, NIWA), New Zealand Association of Scientists president (1998–2000), World Association of Copepodologists president (2008–2011) (born 1940). 17 August – John Bartley, cinematographer (Lost, The X Files, The Chronicles of Riddick), Emmy Award (1996) (born 1947). 18 August Lloyd Ashby, rugby union player (Southland, national team) (born 1931). Lindsay Sparks, cricketer (Central Districts, Auckland) and rugby union player (Marlborough) (born 1944). 19 August – Tony Smith, legal scholar (University of Reading, University of Cambridge, Victoria University of Wellington) (born 1947). 21 August Evelyn Attwood, tennis player (born 1924). Keith Nelson, rugby union player (Otago, Auckland, national team) and dentist (born 1938).
In an incomplete elution, part of the analytes remain in the sorbent because the eluent used does not have a strong enough affinity. Many of the adsorbents/materials are the same as in chromatographic methods, but SPE is distinctive, with aims separate from chromatography, and so has a unique niche in modern chemical science.
Κ-casein labeled with the fluorochrome fluorescein isothiocyanate (FITC) to yield the fluorescein thiocarbamoyl (FTC) derivative. This substrate is used to determinate the milk clotting activity of proteases. FTC-κ-casein method affords accurate and precise determinations of κ-caseinolytic degradation, the first step in the milk-clotting process. This method is the result of a modification to the one described by S.S. Twining (1984). The main modification was substituting the substrate previously used (casein) by κ-casein labeled with the fluorochrome fluorescein isothiocyanate (FITC) to yield the fluorescein thiocarbamoyl (FTC) derivative. This variation allows quantification of the κ-casein molecules degraded in a more precise and specific way, detecting only those enzymes able to degrade such molecules. The method described by Twining (1984), however, was designed to detect the proteolytic activity of a considerably larger variety of enzymes. FTC-κ-casein allows the detection of different types of proteases at levels when no milk clotting is yet apparent, demonstrating its higher sensitivity over currently used assay procedures. Therefore, the method may find application as an indicator during the purification or characterization of new milk-clotting enzymes.
Sources: en.wikipedia.org
In 1868, as a result of the increased use of opium in Britain, the British government restricted the sale of opium by implementing the 1868 Pharmacy Act. In the United States, control of opium remained under the control of individual US states until the introduction of the Harrison Act in 1914, after 12 international powers signed the First International Opium Convention in 1912. Between 1920 and c. 1933, the Eighteenth Amendment to the United States Constitution banned alcohol in the United States. Prohibition proved almost impossible to enforce and resulted in the rise of organized crime, including the modern American Mafia, which identified enormous business opportunities in the manufacturing, smuggling and sale of illicit liquor. The beginning of the 21st century saw drug use increase in North America and Europe, with a particularly increased demand for cannabis and cocaine. As a result, international organized crime syndicates such as the Sinaloa Cartel and 'Ndrangheta have increased cooperation among each other in order to facilitate trans-Atlantic drug-trafficking. Use of another illicit drug, hashish, has also increased in Europe. Drug trafficking is widely regarded by lawmakers as a serious offense around the world. Penalties often depend on the type of drug (and its classification in the country into which it is being trafficked), the quantity trafficked, where the drugs are sold and how they are distributed. If the drugs are sold to underage people, then the penalties for trafficking may be harsher than in other circumstances.
van Krevelen, D.W. (1950). "Graphical-statistical method for the study of structure and reaction processes of coal", Fuel, 29, 269–84. van Krevelen, D.W. and Schuyer, J. (1957) Coal science. Elsevier publishing company. The chemistry and technology of petroleum
Loop diuretics are drugs that are often used for the treatment of hypertension and edema secondary to congestive heart failure, liver cirrhosis, or chronic kidney disease. Their effect, like all diuretics, is to cause the body to excrete more water in the urine. Loop diuretics are more effective than thiazide diuretics in patients with impaired kidney function. They get their name because they affect cells in a structure in the kidney called the loop of Henle.
Sources: en.wikipedia.org
SR9009 is a synthetic research compound that binds and modulates the nuclear receptors REV-ERBα and REV-ERBβ. It is used in laboratory studies of circadian biology and metabolism, not as an approved medicine. It is also known by the informal name Stenabolic.
No. SR9009 has not been approved as a therapeutic drug in the United States, European Union, or other major markets. Human safety and efficacy data are very limited. Its presence in consumer products does not imply regulatory approval.
The World Anti-Doping Agency lists SR9009 as a prohibited substance because it can alter gene expression and metabolic pathways relevant to performance. The ban applies at all times, not only during competition. Detection relies on laboratory methods such as mass spectrometry.
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.