HPLC-MS is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2025-11-05. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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 |
|---|---|---|
| Synonyms | SR9009; Stenabolic | Stenabolic is an informal name |
| Common form | Crystalline powder | Supplied in milligram to gram quantities |
| Long-term storage | -20 °C, desiccated, protected from light | Reduces degradation |
| Detection technique | LC-MS/MS | Common in anti-doping and research analysis |
| Regulatory status | Prohibited in sport by WADA | Not approved for human therapeutic use |
Because REV-ERB receptors are core clock components, SR9009 has been examined for effects on daily rhythms as well as metabolism. Research has explored whether the compound can shift or reinforce circadian gene expression in tissues such as liver and muscle. Some studies report improved metabolic markers in obese or diabetic mice, while others show context-dependent responses. Questions remain about which effects are direct, which are secondary to timing, and how they might differ across species.
SR9009 is a synthetic small molecule studied as an agonist of REV-ERB nuclear receptors. REV-ERB alpha and REV-ERB beta help regulate circadian rhythms and metabolic gene expression. In laboratory research, SR9009 has been used to probe how these receptors affect skeletal muscle, liver, and adipose tissue. The compound was identified in academic drug-discovery work and is often described in scientific literature by its chemical name and research code. It is not an approved medicine, and human clinical data remain limited or absent.
SR9009 binds REV-ERB receptors and alters their repressive activity on target genes. This action can change transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. In rodent studies, treated animals have shown changes in muscle oxidative capacity and exercise performance, though effects vary by dose, duration, and model. The precise molecular steps connecting receptor binding to whole-body outcomes are still an active area of investigation. Findings in animals do not automatically translate to humans.
Detection in biological samples can be complicated by rapid metabolism and low circulating concentrations. Some studies report phase I and phase II metabolites, and analytical methods may need to target those species in addition to the parent compound. Immunoassays are not broadly available, so mass spectrometry remains the main confirmatory approach. For anti-doping testing, laboratories look for SR9009 and its metabolites using validated LC-MS methods. Open questions include how long metabolites remain detectable and how different routes of administration alter detection windows.
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.
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.
For long-term storage, SR9009 is typically kept as a solid at low temperature, protected from moisture and light. Desiccated conditions limit hydrolysis, while opaque containers reduce photochemical breakdown. Solutions are less stable than solids and are often stored frozen in aliquots to avoid repeated freeze-thaw cycles. Stability data are not standardized across all suppliers, so users should rely on certificate-of-analysis information when available. Degradation may appear as color change, precipitate, or decreased chromatographic purity.
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 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.
== Medical uses == Flupirtine is used as an analgesic for acute pain, in moderate-to-severe cases. Its muscle relaxant properties make it popular for back pain and other orthopaedic uses, but it is also used for migraines, in oncology, postoperative care, and gynaecology. In 2013 due to issues with liver toxicity, the European Medicines Agency restricted its use to acute pain, for no more than two weeks, and only for people who cannot use other painkillers.
=== 14 May === Two people were killed by Russian shelling in the Vovchansk area. Russian state media reported that a drone strike derailed a freight train at Kotluban station in Volgograd Oblast. A storage tank carrying diesel caught fire, another exploded and nine rail cars were derailed. Russian Railways said the derailment was a result of "interference by unauthorised persons". No injuries were reported. At least 20 people were injured and fires erupted after a series of Russian airstrikes using new UMPB D-30 glide bombs on residential areas of Kharkiv. French Minister of the Armed Forces Sebastien Lecornu announced another batch of Aster surface-to-air missiles for the Franco-Italian SAMP/T-MAMBA air defenses defending Kyiv.
is the dielectric thickness. In some cases, the hydrophobicity of a substrate can be controlled by using electrical fields. This refers to the phenomenon Electrowetting On Dielectric (EWOD).[3][4] For example, when no electric field is applied to an electrode, the surface will remain hydrophobic and a liquid droplet will form a more spherical droplet with a greater contact angle. When an electric field is applied, a polarized hydrophilic surface is created. The water droplet then becomes flattened and the contact angle decreases. By controlling the localization of this polarization, we can create an interfacial tension gradient that allows controlled displacement of the droplet across the surface of the DMF device.
Women who became pregnant within approximately six months of the final dose showed vaccine efficacy estimates between 57% and 86% against parasitaemia in pregnancy. Because malaria and HIV infections frequently overlap geographically, PfSPZ Vaccine has been studied in HIV-positive adults. A randomized, double-blind, placebo-controlled trial in Tanzania administered five intravenous doses to HIV-negative and well-controlled HIV-positive participants. The vaccine was safe in both groups, but protection against CHMI was observed only in HIV-negative individuals, with an estimated vaccine efficacy of 80% in HIV-negative adults and no measurable efficacy in the HIV-positive cohort. Serological profiling indicated that HIV infection did not markedly diminish the magnitude of antibody responses to key sporozoite antigens, although cellular correlates of protection appear impaired in HIV-positive individuals. Recent analyses have examined the immune targets associated with PfSPZ-induced protection. Whole-proteome antibody profiling in Tanzanian trial participants revealed that vaccination elicits a focused IgG and IgM response to a limited set of Plasmodium falciparum antigens, including circumsporozoite protein and several liver- and blood-stage proteins. A whole-genome sieve analysis of parasites obtained from vaccinated and placebo recipients in West African field trials identified distinct parasite polymorphisms associated with vaccine breakthrough infections.
=== 9/11 response === Following the September 11, 2001, terrorist attacks, President George W. Bush issued Executive Order 13224 under the IEEPA to block the assets of terrorist organizations. The president delegated blocking authority to federal agencies led by the U.S. Treasury. In October 2001, Congress passed the USA PATRIOT Act which, in part, enhanced IEEPA asset blocking provisions under §1702(a)(1)(B) to permit the blocking of assets during the "pendency of an investigation." This statutory change gave the Treasury's Office of Foreign Assets Control the power to block assets without the need to provide evidence of the blocking subject's wrongdoing nor to permit the blocking subject a chance to effectively respond to the allegations in court. Executing these blocking actions led to a series of legal cases challenging federal authority to indefinitely prevent charitable organizations from accessing their assets held in the United States.
Sources: en.wikipedia.org
Indigenous people traded obsidian throughout the Americas. Each volcano and in some cases each volcanic eruption produces a distinguishable type of obsidian allowing archaeologists to use methods such as non-destructive energy dispersive X-ray fluorescence to select minor element compositions from both the artifact and geological sample to trace the origins of a particular artifact. Obsidian cores and blades were traded far inland from the coast. A particularly distant examples of traded obsidian are pieces from the Yellowstone Region found at Hopewell sites, such as Hopewell Culture National Historical Park, Ohio, over 1500 miles away.
==== Improved basic and primary services ==== Improved education, non-farm employment and cash transfers will be key in building capacities to absorb, adapt and transform by rural low-income households, in particular small-scale producers whose livelihoods are increasingly vulnerable to climate shocks and depletion of natural resources. For rural households, FAO's resilience index measurement and analysis (RIMA) model finds that in 23 countries indicate that education, income diversification and cash transfers mainly drove gradual improvements in resilience capacity. Analysis of another 12 countries showed that in more than half of cases, the most important pillar of resilience was access to productive and non-productive assets. Also important to household resilience was adaptive capacity, which depended critically on education and human capacity development within the household. Access to basic services, such as improved sanitation and safe drinking water, and primary services, especially schools, hospitals and agricultural markets, provided important support to household resilience, particularly in very arid zones and in pastoralist households.
South African officials stated that the country had initially expected to attend the summit, while the French government denied having yielded to foreign pressure over the invitation list. Kenya was invited as one of the African partner countries. In late 2025, Macron reportedly considered inviting Chinese leader Xi Jinping to the Évian summit. Japan expressed concern to France that a Chinese invitation could affect G7 unity, amid heightened China–Japan diplomatic tensions.
=== Legal status in the United States === The US government imposed tougher prescribing rules for hydrocodone in 2014, changing the drug from Schedule III to Schedule II. In 2011, hydrocodone products were involved in around 100,000 abuse-related emergency department visits in the United States, more than double the number in 2004.
=== Mass spectrometry === Multiple mass spectrometric techniques, including glow discharge mass spectrometry and direct analysis in real time mass spectrometry rely on Penning ionization. Glow discharge mass spectrometry is the direct determination of trace element in solid samples. It occurs with two ionization mechanisms: the direct electron impact ionization and Penning ionization. Processes inherent to the glow discharge, namely cathodic sputtering coupled with Penning ionization, yield an ion population from which semi-quantitative results can be directly obtained.
Sources: en.wikipedia.org
Laboratories commonly use liquid chromatography coupled with mass spectrometry to detect SR9009. The method can identify the compound and estimate concentration in a sample. Detection limits depend on the matrix and instrument.
Research-grade purity indicates a supplier's measured percentage of the intended compound. It does not guarantee safety, sterility, or suitability for human consumption. Buyers should request a certificate of analysis with chromatograms and test methods.
Sports regulators prohibit SR9009 because it is a non-approved substance with potential performance-altering effects. Its presence can be detected in anti-doping testing. Athletes are responsible for substances found in their samples.
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.