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 2025-11-05. Where a claim depends on a specific study, the study is described rather than over-claimed.
At the molecular level, SR9009 binds REV-ERBα and REV-ERBβ and alters their repressive activity on target genes. These nuclear receptors help regulate the circadian clock, lipid synthesis, glucose metabolism, and inflammatory pathways. By changing transcription, the compound can shift the timing or magnitude of downstream metabolic processes in model systems. It does not act through androgen receptors or adenosine receptors, which distinguishes it from several substances sold for athletic performance. Whether the same transcriptional changes occur in humans at tolerable exposures remains an open question because controlled human studies are lacking.
Preclinical reports describe effects on exercise endurance, mitochondrial content, and lipid profiles in rodents, but these findings come from specific experimental conditions. Many studies use high doses or delivery methods that may not translate directly to human use. SR9009 has been reported to have low oral bioavailability and a short half-life, which complicates interpretation of oral dosing studies. It is not established as safe or effective for any indication. Literature discussions often separate its pharmacological mechanism from unverified claims made in fitness and supplement markets.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C20H24ClN3O4S | Derived from published structure. |
| Molecular weight | 437.94 g/mol | Calculated value. |
| Appearance | White to off-white solid | Typical for purified research samples. |
| Solubility | DMSO, ethanol; low in water | Class: poorly water-soluble. |
| Typical storage | -20 °C, desiccated, protected from light | Limits degradation. |
In laboratory settings, SR9009 is commonly identified by its molecular structure and its interaction with REV-ERB receptors. Vendors may list it under synonyms such as Stenabolic or REV-ERB agonist, but those names do not define purity or identity. Analytical confirmation typically uses high-performance liquid chromatography with ultraviolet detection or liquid chromatography–mass spectrometry. A reference standard is needed to compare retention time and mass spectrum, because the compound can be confused with related research chemicals.
Handling practices for SR9009 focus on minimizing degradation and contamination. The solid is generally stored desiccated at or below -20 °C, protected from light and moisture. Stock solutions are often prepared in dimethyl sulfoxide or ethanol, then aliquoted to avoid repeated freeze–thaw cycles. Aqueous solubility is low, so formulations for animal studies may require cosolvents or suspending agents. Personnel should follow institutional chemical safety procedures, because toxicological data for humans are incomplete.
Regulatory status varies by country and intended use. Major drug agencies have not granted marketing authorization for SR9009 as a medicine, and it is not listed as a controlled substance in many jurisdictions. It is often sold as a research chemical, a category that may fall outside pharmaceutical manufacturing rules. Buyers should verify local laws and supplier documentation, including certificates of analysis. The lack of standardized quality controls raises concerns about identity, purity, and actual content in products marketed online.
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.
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.
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.
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.
=== Neuropad === Neuropad utilizes an adhesive pad with a cobalt (II) salt indicator that changes color from blue to pink in the presence of moisture due to the hydration of cobalt ions. One pad is applied to the plantar surface of each foot in between the 1st and 2nd metatarsal heads. The pad is kept on each foot for ten minutes and the final color is recorded. A full change in color from blue to pink is considered a normal sweat response, while an absent or incomplete color change is considered abnormal. The strengths of Neuropad are its high sensitivity, cost-effectiveness, and its potential as an at-home test. However, Neuropad has lower specificity, is not recommended for children and patients over the age of 70, and is sensitive to certain medications.
The two primary methods of ionization for mass analysis used in droplet-based microfluidics today are matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI). Additional methods for coupling, such as (but not limited to) surface acoustic wave nebulization (SAWN), and paper-spray ionization onto miniaturized MS, are being developed as well.
Due to their numerous sources indoors, concentrations of VOCs indoors are consistently higher (up to ten times higher) than outdoors. VOCs are emitted by thousands of indoor products. Examples include: paints, varnishes, waxes and lacquers, paint strippers, cleaning and personal care products, pesticides, building materials and furnishings, office equipment such as copiers and printers, correction fluids and carbonless copy paper, graphics and craft materials including glues and adhesives, permanent markers, and photographic solutions. Human activities such as cooking and cleaning can also emit VOCs. Cooking can release long-chain aldehydes and alkanes when oil is heated and terpenes can be released when spices are prepared and/or cooked. Cleaning products contain a range of VOCs, including monoterpenes, sesquiterpenes, alcohols and esters. Once released into the air, VOCs can undergo reactions with ozone and hydroxyl radicals to produce other VOCs, such as formaldehyde. Some VOCs are emitted directly indoors, and some are formed through the subsequent chemical reactions. The total concentration of all VOCs (TVOC) indoors can be up to five times higher than that of outdoor levels. New buildings experience particularly high levels of VOC off-gassing indoors because of the abundant new materials (building materials, fittings, surface coverings and treatments such as glues, paints and sealants) exposed to the indoor air, emitting multiple VOC gases.
Sources: en.wikipedia.org
== Properties == DTT is oxidized by air. So it is normally stored and handled under inert atmosphere to minimize oxidation. The rate of air-oxidation is slower at low temperatures. Oxidized DTT exhibits a strong absorbance peak at 280 nm. Since thiols are less nucleophilic than their conjugate bases, thiolates, DTT becomes a less potent nucleophile as the pH falls. (2S)-2-Amino-1,4-dimercaptobutane (dithiobutylamine or DTBA), a related dithiol reducing agent, somewhat overcomes this limitation of DTT. Tris(2-carboxyethyl)phosphine (TCEP) is an alternative reducing agent that is more stable and effective at low pH, but it is bulky and reduces cystines in folded proteins only slowly. DTT's half-life is 40 hours at pH 6.5 and 1.4 hours at pH 8.5 and 20 °C; its half-life decreases further as temperature increases. The presence of EDTA (ethylenediaminetetraacetic acid) to chelate divalent metal ions considerably extends the half-life of DTT in solution.
== Overview == The MCSGP process consists of several, at least two, chromatographic columns which are switched in position opposite to the flow direction. Most of the columns are equipped with a gradient pump to adjust the modifier concentration at the column inlet. Some columns are connected directly, so that non pure product streams are internally recycled. Other columns are short circuited, so that they operate in pure batch mode. The system is split into several sections, from which every section performs a tasks analogous to the tasks of a batch purification. These tasks are loading the feed, running the gradient elution, recycling of weakly adsorbing site fractions, fractionation of the purified product, recycling of strongly adsorbing site fractions, cleaning the column from strongly adsorbing impurities, cleaning in place and re-equilibration of the column to start the next purification run. All of the tasks mentioned here are carried out at the same time in one unit. Recycling of non-pure side fractions is performed in countercurrent movement.
=== 1996 === 8 September The Mystery of the Cocaine Mummies, about pre-Columbian transoceanic contact theories; German toxicologist Svetlana Balabanova made a discovery in a Munich museum; Svetlana, of the Institute of Forensic Science in Ulm, had invented tests for substances in hair and sweat; people did not believe her; toxicologist John Henry of Guy's Hospital; Egyptologist Ann Rosalie David made independent tests at Manchester Museum; Alfred Grimm of the Egyptian Museum in Munich - Staatliche Sammlung für Ägyptische Kunst; Karnak in Egypt; a French TF1 broadcast in 1981; Michelle Lescot of the National Museum of Natural History, France; Nasri Iskander, chief curator of the Egyptian Museum in Cairo; botanist Sandy Knapp of the Natural History Museum, London; John Baines (Egyptologist); anthropologist Alice Beck Kehoe of Marquette University, and early transatlantic ocean crossings; Martin Bernal of Cornell University. Narrated by Robin Ellis, produced by Hilary Lawson, directed by Sarah Marris, made by TVF 15 September The Great Leveller, about psychosomatic medicine, and how work affects our health, and research on health equity carried out by Richard G.
Sources: en.wikipedia.org
== History == The association of elevated intraocular pressure (IOP) and glaucoma was first described by Englishman Richard Banister in 1622: "...that the Eye be grown more solid and hard, then naturally it should be...". Angle-closure glaucoma was treated with cataract extraction by John Collins Warren in Boston as early as 1806. The invention of the ophthalmoscope by Hermann Helmholtz in 1851 enabled ophthalmologists for the first time to identify the pathological hallmark of glaucoma, the excavation of the optic nerve head due to retinal ganglion cell loss. The first reliable instrument to measure intraocular pressure was invented by Norwegian ophthalmologist Hjalmar August Schiøtz in 1905. About half a century later, Hans Goldmann in Bern, Switzerland, developed his applanation tonometer, which, still today, despite numerous innovations in diagnostics, is considered the gold standard of determining this crucial pathogenic factor. In the late 20th century, further pathomechanisms beyond elevated IOP were discovered and became the subject of research, like insufficient blood supply, often associated with low or irregular blood pressure, to the retina and optic nerve head. The first drug to reduce IOP, pilocarpine, was introduced in the 1870s; other major innovations in pharmacological glaucoma therapy were the introduction of beta blocker eye drops in the 1970s and of prostaglandin analogues and topical (locally administered) carbonic anhydrase inhibitors in the mid-1990s.
A 2020 review in The Journal of Bone and Joint Surgery (JB&JS) found it remains broadly popular: ≈2⁄3 of people with OI types III and IV (severe OI) have undergone some form of rodding surgery in their lives, at a mean age of 4+1⁄10 and 7+1⁄2 years respectively; one possible explanation for a tendency towards earlier intervention in type III is that one half of affected children could not walk at all without the surgery, as their limbs were more bowed, so surgery was sought sooner. In those with type III OI who had undergone rodding surgery, 79.5% had the femurs and tibias of both legs rodded. The most common form of rods used are intramedullary (IM) rods, some of which, such as the Fassier–Duval IM rod, are telescoping, meaning that they are designed to grow as the child grows, in an attempt to avoid the necessity of revision surgeries. Telescoping IM rods are widely used, and the common Fassier–Duval IM rod is designed to be used to rod the femur, tibia, and humerus. The surgery involves breaking the long bones in between one and three (or more) places, then fixing the rod alongside the bone to keep it straight. While telescoping IM rods are intended to grow along with both the femur and tibia in developing children; surgeons have a preference to use non-telescoping IM rods, such as Rush rods, in the tibia, which grows less comparatively—the JB&JS review found that while 69.7% of femurs were treated with telescoping IM rods, only 36.9% of tibiae were.
== Structure and discovery == In 1902, Hermann Emil Fischer isolated hydroxyproline from hydrolyzed gelatin. In 1905, Hermann Leuchs synthesized a racemic mixture of 4-hydroxyproline. Hydroxyproline differs from proline by the presence of a hydroxyl (OH) group attached to the gamma carbon atom.
Sources: en.wikipedia.org
SR9009 is a synthetic REV-ERB agonist used in laboratory research. It is not an approved drug, and its effects in humans are not well characterized. It is often sold as a research chemical under the name Stenabolic.
No. SR9009 targets the nuclear receptors REV-ERBα and REV-ERBβ, not the androgen receptor. This mechanism differs from selective androgen receptor modulators and from exercise mimetics that act on PPARδ.
Published evidence is mainly preclinical, using cell cultures and animal models. Controlled human trials are not well documented in the public literature. Claims about human performance or health effects therefore remain unsupported by robust clinical data.
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.