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 2025-11-30. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Scientific discussion of SR9009 often separates animal evidence from human anecdote. Rodent studies provide controlled data on endurance, metabolism, and gene expression, but they use specific strains, doses, and treatment durations. Human reports are mostly uncontrolled and cannot establish cause and effect. Open questions include oral bioavailability, tissue distribution, metabolic stability, and long-term effects. Review articles generally call for more rigorous pharmacokinetic and safety research before any clinical use could be considered.
Analytical methods for SR9009 typically rely on liquid chromatography coupled with tandem mass spectrometry. The technique can separate the parent compound from related substances and detect low concentrations in biological matrices. Urine and blood are common samples in anti-doping testing, while in vitro studies may use cell culture media. Rapid metabolism and low expected concentrations make method validation important for reliable identification. Exact metabolite patterns can vary by species and are not fully mapped.
| 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 |
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.
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.
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.
Preclinical reports have linked SR9009 to improved endurance and altered energy expenditure in rodents. Such findings have prompted interest in whether REV-ERB activation can influence skeletal muscle metabolism. However, the reported effects depend on dose, route, and experimental model, and replication across laboratories is limited. Human trials have not established comparable outcomes, so claims about exercise performance remain speculative. The absence of controlled human data is a central limitation in interpreting these observations.
The mechanism of action involves binding to REV-ERB receptors and recruiting corepressor complexes, which represses target gene transcription. This contrasts with many nuclear receptor agonists that activate transcription. Downstream effects may include changes in autophagy, mitochondrial biogenesis, and lipid handling, but the precise pathways remain an active area of study. Whether these molecular events translate into meaningful physiological effects in humans is unresolved. Most evidence comes from cultured cells and rodent models rather than human participants.
Regulatory treatment of SR9009 varies by country and region. It is not approved as a pharmaceutical, and several jurisdictions restrict its sale for human consumption. Some authorities classify it as a research chemical, a prescription-only substance, or a prohibited performance-enhancing agent in sport. Purchasers may encounter certificates of analysis, but these documents do not guarantee identity, purity, or legality. In research settings, institutional safety reviews and controlled procurement help ensure that materials are handled under appropriate oversight. The absence of harmonized rules means that legal status can change and requires verification.
Analytical identification of SR9009 typically relies on liquid chromatography coupled with tandem mass spectrometry. In biological samples, researchers first separate the compound from matrix components using protein precipitation, liquid-liquid extraction, or solid-phase extraction. High-performance liquid chromatography with ultraviolet detection and nuclear magnetic resonance spectroscopy can support structural confirmation of reference materials. Because SR9009 is a small, relatively lipophilic molecule, reverse-phase columns and acidic mobile phases are common. Laboratories often include isotope-labeled internal standards to improve quantification and to correct for ion suppression.
In March 2013, the City of Pittsburgh filed a lawsuit in Federal court challenging the tax exempt status of UPMC as a public charity, in an effort to make UPMC to pay back taxes. The city alleged that UPMC has abused its status to avoid paying property taxes. The city dropped its lawsuit in 2014. In February 2019, the Pennsylvania Attorney General submitted legal actions against UPMC to enforce requirements for open health care access based on the non-profit status of UPMC. These actions stem from a long-standing dispute between Highmark Health and UPMC, the largest two health-care providers in Western PA. In 2011, Highmark entered a partnership with West Penn Hospital System (now Allegheny Health Network). Because of this competitive threat, UPMC declared they would not accept Highmark Blue Cross Blue Shield Insurance. In order to protect public access to health care while agreements between the two systems unwound, both UPMC and Highmark Health accepted a state-brokered consent decree. With the consent decree expiring in 2019, the Pennsylvania Attorney General attempted to negotiate continued access to care with both companies. Highmark indicated that it would accept the terms while UPMC did not. It is the failure to accept the proposal that the PA Attorney General cited as leading to the legal actions of February 2019.
== Differentiation from tolerance == Tolerance, another condition that can arise from prolonged exposure to opioids, can often be mistaken for opioid-induced hyperalgesia and vice versa, as the clinical presentation can appear similar. Although tolerance and opioid-induced hyperalgesia both result in a similar need for dose escalation to receive the same level of effect to treat pain, they are nevertheless caused by two distinct mechanisms. The similar net effect makes the two phenomena difficult to distinguish in a clinical setting. Under chronic opioid treatment, a particular individual's requirement for dose escalation may be due to tolerance, opioid-induced hyperalgesia, or a combination of both. In tolerance, there is a lower sensitivity to opioids, theorized to occur via two major mechanisms: decreased receptor activation (desensitization of antinociceptive mechanisms) and opioid receptor down-regulation (internalization of membrane receptors). In opioid-induced hyperalgesia, sensitization of pronociceptive mechanisms occurs, resulting in a decrease in the pain threshold, or allodynia. In addition, what appears to be opioid tolerance can be caused by opioid-induced hyperalgesia lowering the baseline pain level, thus masking the drug's analgesic effects. Identifying the development of hyperalgesia is of great clinical importance since patients receiving opioids to relieve pain may paradoxically experience more pain as a result of treatment.
==== Effects on spermatogenesis and fertility ==== Spermatogenesis and male fertility are dependent on FSH, LH, and high levels of testosterone within the testicles. LH does not seem to be involved in spermatogenesis outside of its role in inducing production of testosterone by the Leydig cells in the seminiferous tubules (which make up approximately 80% of the bulk of the testes), whereas this is not the case for FSH, which is importantly involved. In accordance with the fact that the testes are the source of 95% of circulating testosterone in the body, local levels of testosterone inside of the testes are extremely high, ranging from 20- to 200-fold higher than circulating concentrations. Moreover, high levels of testosterone within the testes are required for spermatogenesis, although only a small fraction (5–10%) of normal levels appears to actually be necessary for spermatogenesis. Unlike with antigonadotropic antiandrogens like CPA and GnRH analogues, it has been reported that bicalutamide monotherapy (at 50 mg/day) has very little or no effect on the ultrastructure of the testes and on spermatogenesis in men even after long-term therapy (>4 years). This may be explained by the extremely high local levels of testosterone in the testes, in that it is likely that systemic bicalutamide therapy is unable to achieve concentrations of the drug within the testes that are able to considerably block androgen signaling in this part of the body.
Each subunit has a molecular weight of about 16,000 daltons, for a total molecular weight of the tetramer of about 64,000 daltons (64,458 g/mol). Thus, 1 g/dL=0.1551 mmol/L. Hemoglobin A is the most intensively studied of the hemoglobin molecules. In human infants, the fetal hemoglobin molecule is made up of 2 α chains and 2 γ chains. The γ chains are gradually replaced by β chains as the infant grows. The four polypeptide chains are bound to each other by salt bridges, hydrogen bonds, and the hydrophobic effect.
== Epidemiology == Juvenile Idiopathic Arthritis is the most common chronic rheumatic disease of childhood. In high-income countries, yearly incidence has been estimated at 2–20 cases per 100,000 population; prevalence in these areas is estimated at 16–150 cases per 100,000 population. However, there is also a suggestion that these numbers underestimate disease prevalence: one community-based survey of school children in Western Australia reported a prevalence of 400 per 100,000. Overall prevalence is often reported as one per thousand children. Incidence and prevalence data vary across different population and ethnic groups, with lower overall prevalence in Afro-Caribbean and Asian populations. There are also ethnic differences in the frequency of JIA subtypes: for example, oligoarthritis is the most common subtype in European populations, whilst polyarticular disease predominates in many other countries including Costa Rica, India, New Zealand, and South Africa.
Sources: en.wikipedia.org
Finally, pressure induced phase transitions where the structure of the crystal is altered during the loading are possible. The response of the MOF is predominantly dependent on the linker species and the inorganic nodes. However, certain MOFs exhibit guest-dependent crystal polymorphism, where different guest molecules can induce distinct crystal phases or configurations. This phenomenon results in MOF crystal structures that change depending on the composition of the surrounding gaseous environment.
On July 5, 1932, to honor the memory of the recently deceased Dr. Llansó, the name was changed again to the Hogar Nacional Masónico Llansó (English: Llansó National Masonic Retirement Home), and its mission was changed from being a homeless shelter to that of a retirement home and hospice for the elderly.
=== India === In India, after completing MBBS degree and one year of integrated internship, doctors can enroll in several types of postgraduate training programs: M.D. (DOCTOR OF MEDICINE) in: Anesthesiology, Anatomy, Biochemistry, Community Medicine, Dermatology Venereology and Leprosy, General Medicine, Forensic Medicine, Microbiology, Pathology, Paediatrics, Pharmacology, Physical medicine and rehabilitation, Physiology, Psychiatry, Radio diagnosis, Radiotherapy, Tropical Medicine, and, Tuberculosis & Respiratory Medicine. M.S. (MASTER OF SURGERY) in: Otorhinolaryngology, General Surgery, Ophthalmology, Orthopaedics, Obstetrics & Gynecology. D.M. (DOCTOR OF MEDICINE) in: Cardiology, Endocrinology, Medical Gastroenterology, Nephrology, and Neurology. M.Ch. (MASTER OF CHIRURGIE) in: Cardio vascular & Thoracic Surgery, Urology, Neurosurgery, Paediatric Surgery, Plastic Surgery. Or diploma in: Anesthesiology (D.A.), Clinical Pathology (D.C.P.), Dermatology Venereology and Leprosy (DDVL), Forensic Medicine (D.F.M.), Obstetrics & Gynaecology (D.G.O.), Ophthalmology (D.O.), Orthopedics (D.Ortho.), Otorhinolaryngology (D.L.O.), Paediatrics (D.C.H.) Psychiatry (D.P.M.), Public health (D.P.H.), Radio-diagnosis (D.M.R.D.), Radiotherapy (D.M.R.T.)., Tropical Medicine & Health (D.T.M. & H.), Tuberculosis & Chest Diseases (D.T.C.D.), Industrial Health (D.I.H.), Maternity & Child Welfare (D. M. C. W.)
=== Efforts to reduce recreational use in the US === In 2011, the Obama administration released a white paper describing the administration's plan to deal with the opioid crisis. The administration's concerns about addiction and accidental overdosing have been echoed by numerous other medical and government advisory groups around the world. As of 2015, prescription drug monitoring programs exist in every state except for Missouri. These programs allow pharmacists and prescribers to access patients' prescription histories in order to identify suspicious use. However, a survey of US physicians published in 2015 found that only 53% of doctors used these programs, while 22% were not aware that the programs were available to them. The Centers for Disease Control and Prevention (CDC) was tasked with establishing and publishing a new guideline, and was heavily lobbied. In 2016, the CDC published its Guideline for Prescribing Opioids for Chronic Pain, recommending that opioids only be used when benefits for pain and function are expected to outweigh risks, and then used at the lowest effective dosage, with avoidance of concurrent opioid and benzodiazepine use whenever possible. Research suggests that the prescription of high doses of opioids related to chronic opioid therapy (COT) can at times be prevented through state legislative guidelines and efforts by health plans that devote resources and establish shared expectations for reducing higher doses. On 10 August 2017, Donald Trump declared the opioid crisis a (non-FEMA) national public health emergency.
Sources: en.wikipedia.org
In the early 20th century, taxidermy was taken forward under the leadership of artists such as Carl Akeley, James L. Clark, William T. Hornaday, Coleman Jonas, Fredrick, and William Kaempfer, and Leon Pray. These and other taxidermists developed anatomically accurate figures which incorporated every detail in artistically interesting poses, with mounts in realistic settings and poses that were considered more appropriate for the species. This was quite a change from the caricatures popularly offered as hunting trophies. Additional modern uses of taxidermy have been the use of "faux taxidermy" or fake animal heads that draw on the inspiration of traditional taxidermy. Decorating with sculpted fake animal heads that are painted in different colors has become a popular trend in interior design.
==== China ==== Within China, extensive border controls are maintained for those travelling between the mainland and the special administrative regions of Hong Kong and Macau. Foreign nationals need to present their passports or other required travel documents when travelling between these jurisdictions. For Chinese nationals (including those with British National (Overseas) status), there are special documents for travel between these territories. Internal border controls in China have also led to the creation of special permits that allow Chinese citizens to immigrate to or reside in other immigration areas within the country. China also maintains distinct, relaxed border control policies in the Special Economic Zones of Shenzhen, Zhuhai and Xiamen. Nationals of most countries can obtain a limited area visa upon arrival in these regions, which permits them to stay within these cities without proceeding further into other parts of mainland China. Visas for Shenzhen are valid for 5 days, and those for Xiamen and Zhuhai are valid for 3 days. The duration of stay starts the day after arrival. The visa can only be obtained only upon arrival at Luohu Port, Huanggang Port Control Point, Fuyong Ferry Terminal or Shekou Passenger Terminal for Shenzhen; Gongbei Port of Entry, Hengqin Port or Jiuzhou Port for Zhuhai; and Xiamen Gaoqi International Airport for Xiamen.
Some gas panels have a separate supply gauge for each diver downstream of the supply valve, but this is not standard practice. The gas panel may be fairly large and mounted on a board for convenience of use, or may be compact and mounted inside a portable box, for ease of transport. Gas panels are usually for one, two or three divers. In some countries, or under some codes of practice, the surface standby diver must be supplied from a separate panel to the working diver/s. A wet or closed bell will be fitted with a bell gas panel to supply gas to the divers' excursion umbilicals. The bell gas panel is supplied with primary gas from the surface via a bell umbilical, and on-board emergency gas from high-pressure storage cylinders mounted on the frame of the bell.
The brewery hired the statistician William Sealy Gosset in 1899, who achieved lasting fame under the pseudonym "Student" for techniques developed for Guinness, particularly Student's t-distribution and the even more commonly known Student's t-test. By 1900 the brewery was operating unparalleled welfare schemes for its 5,000 employees. By 1907 the welfare schemes were costing the brewery £40,000 a year, which was one-fifth of the total wages bill. The improvements were suggested and supervised by Sir John Lumsden. By 1914, Guinness was producing 2.652 million barrels of beer a year, which was more than double that of its nearest competitor Bass, and was supplying more than 10 per cent of the total UK beer market. When World War I broke out in 1914, employees at Guinness St. James Brewery were encouraged to join the British forces. Over 800 employees served in the war. This was made possible due to a number of measures put in place by Guinness: soldiers' families were paid half wages, and jobs were guaranteed upon their return. Of the 800 employees who fought, 103 did not return. During World War II, the demand for Guinness among the British was one of the main reasons why the UK lifted commerce restrictions imposed in 1941 to force Ireland into supporting the Allied Powers. Before 1939, if a Guinness brewer wished to marry a Catholic, his resignation was requested.
== Contesting parties == Sixty parties won votes at the election, of which twenty-one secured seats. A total of 57 political parties registered party lists. The first 52 party numbers were selected by lottery, and the last five were selected chronologically. Registration closed on 1 January 2026 with more than 5,000 constituency and party-list candidates and 94 prime ministerial candidates on the books.
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.
No. It is an investigational compound without approved therapeutic indications. It is sold for research purposes only in many jurisdictions.