This is a working overview of LC-MS, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-04-27 and is reviewed periodically as new material appears.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | -20 °C or lower | Desiccated and protected from light |
| Common analytical method | LC-MS/MS | Detects parent drug and metabolites |
| Solubility class | Lipophilic; soluble in organic solvents | Low aqueous solubility |
| Molecular weight | 437.94 g/mol | Calculated from reported formula |
| Synonyms | SR9009; REV-ERB agonist | Code name used in scientific literature |
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.
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.
Examples of antagonists, or more appropriately named receptor channel blockers, of the NMDA receptor are APV, amantadine, dextromethorphan (DXM), ketamine, magnesium, tiletamine, phencyclidine (PCP), riluzole, memantine, methoxetamine (MXE), methoxphenidine (MXP) and kynurenic acid. While dizocilpine is generally considered to be the prototypical NMDA receptor blocker and is the most common agent used in research, animal studies have demonstrated some amount of neurotoxicity, which may or may not also occur in humans. These compounds are commonly referred to as NMDA receptor antagonists.
Motilin is a 22-amino acid polypeptide hormone in the motilin family that, in humans, is encoded by the MLN gene. Motilin is secreted by endocrine Mo cells (also referred to as M cells, which are not the same as the M cells, or microfold cells, found in Peyer's patches) that are numerous in crypts of the small intestine, especially in the duodenum and jejunum. It is released into the general circulation in humans at about 100-min intervals during the inter-digestive state and is the most important factor in controlling the inter-digestive migrating contractions; and it also stimulates endogenous release of the endocrine pancreas. Based on amino acid sequence, motilin is unrelated to other hormones. Because of its ability to stimulate gastric activity, it was named "motilin." Apart from in humans, the motilin receptor has been identified in the gastrointestinal tracts of pigs, rats, cows, and cats, and in the central nervous system of rabbits.
== Computer-aided drug design == The most fundamental goal in drug design is to predict whether a given molecule will bind to a target and if so how strongly. Molecular mechanics or molecular dynamics is most often used to estimate the strength of the intermolecular interaction between the small molecule and its biological target. These methods are also used to predict the conformation of the small molecule and to model conformational changes in the target that may occur when the small molecule binds to it. Semi-empirical, ab initio quantum chemistry methods, or density functional theory are often used to provide optimized parameters for the molecular mechanics calculations and also provide an estimate of the electronic properties (electrostatic potential, polarizability, etc.) of the drug candidate that will influence binding affinity. Molecular mechanics methods may also be used to provide semi-quantitative prediction of the binding affinity. Also, knowledge-based scoring function may be used to provide binding affinity estimates. These methods use linear regression, machine learning, neural nets or other statistical techniques to derive predictive binding affinity equations by fitting experimental affinities to computationally derived interaction energies between the small molecule and the target. Ideally, the computational method will be able to predict affinity before a compound is synthesized and hence in theory only one compound needs to be synthesized, saving enormous time and cost.
The nucleoside cytosine has a half-life in isolation of 19 days at 100 °C (212 °F) and 17,000 years in freezing water, which some argue is too short on the geologic time scale for accumulation. Others have questioned whether ribose and other backbone sugars could be stable enough to be found in the original genetic material, and have raised the issue that all ribose molecules would have had to be the same enantiomer, as any nucleotide of the wrong chirality acts as a chain terminator. Pyrimidine ribonucleosides and their respective nucleotides have been prebiotically synthesised by a sequence of reactions that by-pass free sugars and assemble in a stepwise fashion by including nitrogenous and oxygenous chemistries. In a series of publications, John Sutherland and his team at the School of Chemistry, University of Manchester, have demonstrated high yielding routes to cytidine and uridine ribonucleotides built from small 2- and 3-carbon fragments such as glycolaldehyde, glyceraldehyde or glyceraldehyde-3-phosphate, cyanamide, and cyanoacetylene. One of the steps in this sequence allows the isolation of enantiopure ribose aminooxazoline if the enantiomeric excess of glyceraldehyde is 60% or greater, of possible interest toward biological homochirality. This can be viewed as a prebiotic purification step, where the said compound spontaneously crystallised out from a mixture of the other pentose aminooxazolines. Aminooxazolines can react with cyanoacetylene in a mild and highly efficient manner, controlled by inorganic phosphate, to give the cytidine ribonucleotides.
Although one-letter symbols are included in the table, IUPAC–IUBMB recommend that "Use of the one-letter symbols should be restricted to the comparison of long sequences". The one-letter notation was chosen by IUPAC-IUB based on the following rules:
Sources: en.wikipedia.org
Farhad Hafezi (born 1 November 1967) is a Swiss eye surgeon and researcher. Hafezi first gained recognition as a leading retina researcher in 1994, having been the first to discover a gene responsible for light-induced retinal degeneration. However, he changed his research focus to the cornea in 2003, and it is this work, particularly on corneal collagen cross-linking (CXL), which he helped pioneer, and advanced laser refractive surgery that he is internationally known for today. Hafezi's current clinical and laboratory research is focused on gaining a better understanding of the cornea. His research group at the University of Zurich has three main research foci:
==== Pure collagen scaffolds ==== Collagen is the primary component of the extracellular matrix. Collagen scaffolds efficiently support fibroblast growth, which in turn allows keratinocytes to grow nicely into multilayers. Collagen (mainly collagen type I) is often used as a scaffold because it is biocompatible, non-immunogenic and available. However, collagen biodegrades relatively rapidly and is not good at withstanding mechanical forces. Improved characteristics can be created by cross-linking collagen-based matrices: this is an effective method to correct the instability and mechanical properties.
=== Secondary intention === Secondary intention is implemented when primary intention is not possible because of significant tissue damage or loss, usually due to the wound having been created by major trauma. The wound is allowed to granulate. Surgeon may pack the wound with a gauze or use a drainage system. Granulation results in a broader scar. Healing process can be slow due to presence of drainage from infection. Wound care must be performed daily to encourage wound debris removal to allow for granulation tissue formation. Using antibiotics or antiseptics for the surgical wound healing by secondary intention is controversial. Examples: gingivectomy, gingivoplasty, tooth extraction sockets, poorly reduced fractures, burns, severe lacerations, pressure ulcers. There is insufficient evidence that the choice of dressings or topical agents affects the secondary healing of wounds. There is lack of evidence for the effectiveness of negative pressure wound therapy in wound healing by secondary intention.
=== Disadvantages === The used fuel is difficult and dangerous to reprocess because many of the daughters of 232Th and 233U are strong gamma emitters. All 233U production methods result in impurities of 232U, either from parasitic knock-out (n,2n) reactions on 232Th, 233Pa, or 233U that result in the loss of a neutron, or from double neutron capture of 230Th, an impurity in natural 232Th:
Selenoinsulin (abbreviated to Se-Ins) is an experimental insulin analogue first described in 2017. It is a modified form of bovine pancreatic insulin in which the interchain disulfide bond between residues A7 and B7 is replaced with a diselenide bond formed by two selenocysteine residues. In laboratory studies, selenoinsulin retained biological activity comparable to that of bovine pancreatic insulin and showed greater resistance to degradation by the insulin-degrading enzyme (IDE).
Sources: en.wikipedia.org
Metabolism and biosynthesis of serotonin. Pyridoxal phosphate is a cofactor of aromatic L-amino acids decarboxylase. This allows for conversion of 5-hydroxytryptophan (5-HTP) into serotonin (5-HT). This reaction takes place in serotonergic neurons. Metabolism and biosynthesis of histamine. Pyridoxal phosphate is a cofactor of L-histidine decarboxylase. This allows for conversion of histidine into histamine. This reaction takes place in Golgi apparatus in mast cells and in basophils. Next, histamine is stored in granularity in mast cells as a complex with acid residues of heparin proteoglycan while in basophils as a complex with chondroitine sulfate. Metabolism and biosynthesis of GABA (γ-aminobutyric acid). Pyridoxal phosphate is a cofactor of glutamic acid decarboxylase (GAD). This allows for conversion of glutamate into GABA. Reaction takes place in cytoplasm of termination of GABA-ergic neurons, therefore vitamin B6 deficiency may cause epileptic seizures in children. Pyridoxal phosphate also participates in the oxidative deamination of GABA, where it is a cofactor of GABA aminotransferase. Metabolism of ornithine. Pyridoxal phosphate is a cofactor of ornithine decarboxylase. It is therefore associated with the synthesis of polyamines; crucial compounds associated with cell growth and proliferation. Transamination. Pyridoxal phosphate takes part in decomposition and synthesis of amino acids, fats, and carbohydrates, and in the biosynthesis of hormones, neurotransmitters, and heme.
Fossils of what are thought to be filamentous photosynthetic organisms have been dated at 3.4 billion years old. More recent studies also suggest that photosynthesis may have begun about 3.4 billion years ago, though the first direct evidence of photosynthesis comes from thylakoid membranes preserved in 1.75-billion-year-old cherts. Oxygenic photosynthesis is the main source of oxygen in the Earth's atmosphere, and its earliest appearance is sometimes referred to as the oxygen catastrophe. Geological evidence suggests that oxygenic photosynthesis, such as that in cyanobacteria, became important during the Paleoproterozoic era around two billion years ago. Modern photosynthesis in plants and most photosynthetic prokaryotes is oxygenic, using water as an electron donor, which is oxidized to molecular oxygen in the photosynthetic reaction center.
Finals appearances were rare for the side, which was often in contention for the wooden spoon. Essendon did manage to make the 1968 VFL Grand Final, but it lost to Carlton by just three points and did not make it back to the big stage for 15 years. During the period from 1968 until 1980, five different coaches were tried, with none lasting longer than four years. Off the field, the club went through troubled times as well. In 1970, five players went on strike before the season even began, demanding higher payments. Essendon did make the finals in 1972 and 1973 under the autocratic direction of Des Tuddenham (Collingwood), but they were beaten badly in successive elimination finals by St. Kilda and did not taste finals action again until the very end of the decade. The 1970s Essendon sides were involved in many rough and tough encounters under Tuddenham, who himself came to loggerheads with Ron Barassi at a quarter-time huddle where both coaches exchanged heated words. Essendon had tough but talented players with the likes of Ron "Rotten Ronnie" Andrews and experienced players such as Barry Davis, Ken Fletcher, Geoff Blethyn, Neville Fields and Western Australian import Graham Moss. In May 1974, a controversial half-time all-in-brawl with Richmond at Windy Hill and a 1975 encounter with Carlton were testimony to the era. Following the Carlton match, the Herald described Windy Hill as "Boot Hill" because of the extent of the fights and the high number of reported players (eight in all — four from Carlton and four from Essendon).
Ligand-targeted liposomes utilize active targeting to interact with the desired cells. Once administered intravenously into blood circulation, ligand-targeted liposomes must travel to reach the target area to deliver their contents. LTLs retain the contained agent until the process of cellular uptake. Receptor-mediated endocytosis is the most common way LTLs deliver material to the cell. The targeting ligand connected to the liposome attaches to the binding site found on the targeted cell. The LTL's contents are transported to Lysosomes to be processed. This process allows the molecules to cross the blood-brain barrier, which allows the drug to be delivered to tissue that is relatively difficult to reach without a specific mechanism. Less commonly, pinocytosis or phagocytosis may be used for cellular uptake of the liposome. Certain recognition sites, such as ecto-NAD+oglycohydro|ase, mediate uptake to aid in the internalization and effectiveness of the LTLs. The remainder of LTLs in circulation after binding to the target site are mainly cleared through the reticuloendothelial system (RES). The RES includes different organs including the kidneys, lungs, spleen, liver, bone marrow, and lymph nodes. The liver is the primary organ for the clearance of LTLs. The RES is most likely able to clear LTLs due to fenestrations in their microvasculature that allow for extravasation. Phagocytic cells within the RES break down LTLs.
== Biography == Born on 27 September 1958 in the Indian state of Maharashtra, K. V. Subba Rao graduated in science from the University of Pune and before starting his career by joining Malti-Chem Research Centre, Baroda, he secured his master's degree also from the same university in 1979. Subsequently, he did his doctoral studies under Sukhdev at Maharaja Sayajirao University of Baroda and moved to Johns Hopkins University in 1983 for his post-doctoral studies at their Division of Environmental Chemistry where he worked with Miles R. Chedekel. After working for two years there, he joined the laboratory of Fred C. Fox at the University of California and worked there for three more years. Returning to India in 1988, he joined the International Centre for Genetic Engineering and Biotechnology where he held different positions as that of a research scientist (1988–91) and research assistant (1991–94) and was the Group Leader of the Immunology Group (1994-2015).
Sources: en.wikipedia.org
Liquid chromatography-tandem mass spectrometry is a common approach. It can detect the parent compound and its metabolites in biological matrices.
Research samples are typically kept frozen, desiccated, and protected from light. Stock solutions are often aliquoted to reduce freeze-thaw cycles.
High-performance liquid chromatography and nuclear magnetic resonance are standard for purity and identity. Mass spectrometry confirms molecular weight.
It is a synthetic research compound that activates REV-ERB nuclear receptors. It is not an approved drug or dietary supplement. Most information comes from cell and animal studies.